Did you know that our bodies create about a gallon of mucus in just two days! I do. In fact, I know a lot of other interesting information about the human body, and YOU WILL TOO if you read my paper! Within this document, you will find six different body system essays. Within this document, you will find six different body system essays including the muscular, skeletal, circulatory, respiratory, digestive, and nervous systems, which all work together to operate our body. All of these systems have different components, each with their unique functions that help keep us alive. However, each of these systems cannot operate alone - they need each other to be successful. For example, the nutrients gathered by the digestive system get distributed throughout the body in the circulatory system! Over the previous 12 weeks, we gathered information, organized our thoughts, and paraphrased what trusted websites taught us about each system. We worked with responsibility partners and our papers definitely benefited from the collaboration. Just like the human body system rely on the other systems, we relied on each other to improve our writing and our process. The following is the result of our hard work...
Skeletal System.
Our skeletal system is made up of 206 bones. These bones work together to provide our body with support so that we can stand, help us move so we can walk around, and protect our vital organs like our heart and brain! Our bones even make and store blood cells for our circulatory system! Without our bones, we would be nothing more than a pile of skin, organs, and muscles on the floor. We wouldn’t be able to move and our organs wouldn’t be safe!
Our bones are made up of many layers. These layers are important because we need our bones to be strong, yet lightweight. In order to achieve this goal, the outside layer of bone is made up of solid, compact bone that makes our bones strong and dense. The next layer of bone is called cancellous bone (a.k.a. spongy bone.) This layer allows our bones and allows our bones to be lightweight and transitions us from compact bone into bone marrow. Bone marrow is a thick and spongy section in the middle of bone where red and white blood cells are formed. Finally, our bones our covered in a thin membrane called periosteum which is where our muscles attach to bones. So that is how bones are structured in order to keep our bodies strong, yet lightweight.
Although bones are extremely important they wouldn’t be able to move without joints! Joints are places where two or more joints meet. There are several types of joints in our bodies, but we’ll just focus on four of them. The first type of joint is called a hinge joint. Just like the...
Skeletal System.
Our skeletal system is made up of 206 bones. These bones work together to provide our body with support so that we can stand, help us move so we can walk around, and protect our vital organs like our heart and brain! Our bones even make and store blood cells for our circulatory system! Without our bones, we would be nothing more than a pile of skin, organs, and muscles on the floor. We wouldn’t be able to move and our organs wouldn’t be safe!
Our bones are made up of many layers. These layers are important because we need our bones to be strong, yet lightweight. In order to achieve this goal, the outside layer of bone is made up of solid, compact bone that makes our bones strong and dense. The next layer of bone is called cancellous bone (a.k.a. spongy bone.) This layer allows our bones and allows our bones to be lightweight and transitions us from compact bone into bone marrow. Bone marrow is a thick and spongy section in the middle of bone where red and white blood cells are formed. Finally, our bones our covered in a thin membrane called periosteum which is where our muscles attach to bones. So that is how bones are structured in order to keep our bodies strong, yet lightweight.
Although bones are extremely important they wouldn’t be able to move without joints! Joints are places where two or more joints meet. There are several types of joints in our bodies, but we’ll just focus on four of them. The first type of joint is called a hinge joint. Just like the...
...hinges on a door, they allow movement back and forth. We have hinge joints at our elbows and our knees, and we even have them in our knuckles! Another type of of joint is called a ball and socket joint. This is a where one bone has a ball at the the end of it and the other bone has a “baseball mitt” for the ball to sit in. Our shoulders and hips are examples of ball and socket joints.
Muscular System:
The muscular system helps the human body move around and have fun. Let’s say you want to move your arms around, eat a sandwich, or run, you use muscles! They are many different types of muscles they all serve different purposes (e.g. movement, pumping blood, and dilating your pupils. Some of these purposes are controlled by us, while others are controlled automatically by the muscle cell or the brain.
There are two types of categories of muscles in the human body: voluntary and involuntary. Voluntary muscles are muscles that we have control over. They are the muscles that control body’s movements and are attached to bones. Skeletal muscles are the only type of voluntary muscles in our body. They pull on bones to cause us to move. Skeletal muscles never push, they only pull, and that’s why they are nearly always found in pairs. One example of this is the biceps and triceps that are located in our upper arms. When the biceps want to the lower arm up, they contract or shrink, while triceps relax or expand. When the the triceps want to pull the arm down, they contract while the biceps relax. This is an example of a pair of muscles working together. But those muscles wouldn’t be able to do any of this without tendons connecting them to the bones that they move! Tendons are flexible bands of tissue that blend into bones and enable them to move the move the bones that they are supposed to move. Although skeletal muscles are the only type of voluntary muscles, there are two different types of involuntary muscles!
Unlike voluntary muscles, involuntary muscles do things automatically without us knowing it. There are two examples of involuntary muscles. They are cardiac muscle and smooth muscle. Cardiac and smooth muscles are similar because they work automatically, by themselves. Cardiac muscles are muscles,are muscles that are only found in our heart, and are responsible for pumping blood throughout our body. They work without us thinking about them, and they contract and relax throughout our entire lives. Smooth muscles are found inside your organs (e.g. intestines, esophagus, stomach, and bladder) and help move throughout our body. Smooth muscles can also be found in your your eyes and your blood vessels. Smooth muscle cells look like on big cell, but are actually a bunch of smaller, smooth cells all grouped together (unlike strained cells.) So clearly, there are many types of involuntary muscles in our body that do things we had no idea about. Including important tasks like pumping blood and digestive food!
The muscular system is a powerful system that allows us to move, convert food into energy, and circulate blood throughout our body. Our muscles make up over half of our body weight and give or body shape. In the next essay, learn how some of these muscles move blood throughout our body in order to deliver oxygen to all of our cells.
Circulatory System:
Your Circulatory System is in charge of circulating blood throughout your body hence the name circulatory system. Your circulatory system delivers blood with oxygen in it called oxygenated blood to all of your cells and brings waste rich blood, deoxygenated blood back to you lungs to breathe out. Your blood cells carry the nutrients, oxygen, and hormones but your blood flows through blood vessels which carry the blood cells to their destination. It’s all like a cycle your lungs breathe in oxygen the blood cells are oxygenated then they flow through the heart which pump them out in your arteries which carry them all over your body. Next the waste rich blood flows back in your veins to your heart where they get pumped back to your lungs to breathe out the waste and collect oxygen, and back through the heart and into the arteries. So as you can see your Circulatory System is an essential part of your life and has a lot to discover about it.
Your Circulatory System is what makes your heart pump blood and keeps your body going. Your blood is like a transport system delivering oxygen and nutrients to your cells and taking waste away. But that’s not all your blood is in charge of! Your blood is also responsible for combating against disease and helping you stay healthy. Blood’s third responsibility is to circulate heat throughout your body and keep you warm. Your blood also carries hormones throughout your body. Your blood is basically the master of multitasking balancing all the responsibilities throughout your body. You have different blood cells that make up your blood. First you have your red blood cells which are in charge of delivering oxygen and taking carbon dioxide to your lungs so they can breathe it out. There are millions of red blood cells in a drop of blood and they last 4 months before turning into new blood. Red blood cells are made in the bone marrow in lots of your bones. You also have something called White Blood cells which are the ones that help you stay healthy. White blood cells are the defenders of your body you usually have around 5,000 to 7,000 white blood cells in a milliliter of blood. When you are sick you can have around 25,000 per milliliter fighting off the bacteria. White blood cells work with something called antibodies and help combat against germs and diseases. Platelets are another part of our blood and they help plug up wounds. When you get hurt your platelets go and stick to stop the blood and they attract other platelets. The scab you get after you get a cut is actually platelets once they harden! Plasma makes up about half of your blood it is a liquidy yellow substance. Plasma carries around nutrients, hormones, proteins, and cells that float in it. Your plasma takes away waste and is made in the liver. Clearly your blood has many different interesting and complex parts.
Your blood is definitely important but what does it flow through? Why blood vessels of course! Blood vessels are the highways going through your body routing your blood to where they need to be. Blood vessels may be tiny but that doesn’t mean they aren’t mighty. Did you know that if you took all the blood vessels out of a kid they would be 60,000 miles long in adults they are 100,000 miles long! There are three kinds of blood vessels: Arteries, Veins, and Capillaries. Arteries carry oxygenated blood away from the heart. Arteries are hard on the outside but have a softer muscle inside to move the blood around your body. The arteries have to be very thick to withstand the pressure from the heart pumping really hard. The arteries get smaller and smaller until they turn into capillaries. Capillaries are the things that connect arteries to veins. The arteries deliver the oxygenated blood to the capillaries. Next the capillaries deliver waste rich blood to the veins. Veins carry the waste rich blood back to the heart. Veins aren’t as strong as arteries because they don’t have to withstand the pressure from the heart sending out blood. Veins, unlike arteries, have valves that make sure the blood is only flowing in one direction arteries don’t need valves because the heart pumps very hard so the blood only flows where the heart pushes it. Valves also help the blood come back to the heart against gravity! Now you know just how important your blood vessels are they help guide the blood to where it needs to be.
Your heart is the last part off the transport system we have our train the blood, our track the blood vessels, and last we have the station our heart. Your heart is seated in between your lungs and it serves to deliver your blood, which holds many nutrients along with oxygen that goes to every organ, tissue, and cell in your body. You need your heart to deliver oxygen and remove waste which would otherwise become dangerous. Your heart is constantly pumping new blood out to keep you alive. Your heart has four different chambers that work together the right atrium, left atrium, right ventricle, and left ventricle. Blood is pushed from the two atriums into both ventricles. Valves open between them making sure the blood only flows one way. Your left atrium receives oxygenated blood from the lungs and then sends it over to the left ventricle. Your left ventricle gets the blood from the left atrium and then has to pump the blood out to your entire body. You left ventricle is the thickest of any of the four chambers! Next we have your right atrium which receives deoxygenated blood. Then the right atrium sends the blood into the right ventricle. The right ventricle gets the blood and sends it to the lungs. The blood is sent to the lung so the waste can be breathed out and the blood will get oxygenated again. Your circulatory system is like a big loop with your heart in the middle, sending deoxygenated blood out taking new oxygenated blood back all in a big circle happening again and again always beating until you die.
You learned your Circulatory system is important it keeps you living because without your circulatory system your cells wouldn’t get oxygen and they would die. Your Circulatory System harmonizes perfectly from the blood, blood vessels, and heart working together to your four chambers working together. Your circulatory system definitely has to work hard but you don’t your heart is an involuntary muscle so your heart pumps without you even thinking about it! The Circulatory system is amazing and it is definitely interesting with all of its different parts there is so much to learn. We need another system to oxygenate our blood called the circulatory system.
Respiratory System:
The respiratory system is in charge of breathing but it also gives you the ability to make noise and smell things. The respiratory system has many parts but here are some of the main parts the nose, trachea, bronchi, lungs, alveoli, and the diaphragm. The process of breathing starts when air comes in your nose and the air is filtered. Then the air has to pass by that flap of cartilage in the back of your throat. Then the air passes through a series of tubes and then the oxygen enters your blood and carbon dioxide gets breathed back out into the air. The respiratory system has a lot more to it than just breathe in then breathe out.
The respiratory system starts with taking in air through the mouth or nose. When you take air through your mouth or nose it makes the air warm and wet because cold dry air irritates the lungs. In both the nose and mouth the air becomes warm and wet. In the nasal passage there are little tiny hairs called cilia and mucus that trap any pollen, dust, and mold before they can get to the lungs. The nasal passage or cavity does this because if the air going to the lungs is dry, cold, and filled with dust particles it will irritate the lungs. After the air passes through your nasal passage it has to get past the epiglottis. The epiglottis is a flap of cartilage that flops around in front of your windpipe. Without the epiglottis whenever you ate food or drank you would choke and die. The Larynx known as the voice box is home to the vocal chords and is involved in breathing, sound production, sound amplification, and and protecting the trachea. The Larynx connects the Pharynx and Trachea and allowing air though and keeping food and drink out. The vocal folds also known as vocal cords are set of twin mucous membranes. The air that you take in vibrates the vocal folds and makes the noise that ables you to speak and sing. Your voice box makes sure that there is a safe passageway for the air to go through. The next part of your body the air travels through is the trachea. The trachea commonly referred to as the windpipe is what connects the larynx to the bronchial tubes. The trachea is an essential part of the respiratory system and helps out delivering air to the lungs. Now the air reaches the lungs but it doesn’t stop there.
The air is now inside an important organ the lungs. The lungs main purpose is to help oxygen enter your bloodstream and carbon dioxide out of your body. Your lungs are important but they don’t do the actual putting oxygen in red blood cells they just help. After the air comes out of the trachea into the bronchial tubes which connect to the top part of your lungs known as the hilum. The bronchial tubes let air in and out of your lungs through the trachea. One bronchial tube is called bronchus and there are two, one for each lung. The bronchial tubes bring air from the trachea to the bronchi. The bronchi are the main passageways that bring air through the lungs. The bronchi are just the bronchial tubes getting smaller and going deeper into your lungs. When our bronchi split apart we get the bronchioles. Our bronchioles are the last airway the air has to pass through before all the real action happens. The alveoli are the little air sacs at the very end of the bronchioles. Even though they are tiny the alveoli do a lot of hard work. The alveoli are grouped together in clusters instead of being on their own. There are millions of alveoli in your body they take up a surface area of about 70 meters squared, and if they could be stretched out they would cover an entire tennis court. The gas exchange takes place in the alveoli it swaps carbon dioxide and oxygen. The carbon dioxide in the red blood cells has to go into the alveoli while the oxygen has to go in the red blood cells. What happens is the oxygen and carbon dioxide go through the alveoli walls, and then the oxygen goes into the capillaries and oxygenates your red blood cells. The carbon dioxide goes into the alveoli and then up further to the bronchioles. The carbon dioxide has to go in the same route as the oxygen came down in just reverse order. That may sound like that is all there could be in the respiratory system but there is one other essential part of the respiratory system. The next part of the respiratory system is the diaphragm which is a muscle located underneath the lungs. Without the diaphragm we wouldn’t be able to breathe. When the diaphragm contracts you breath in, and when the diaphragm relaxes you breathe out. Our diaphragm is an important part of our respiratory system. The respiratory system as you saw is a little confusing but very important to our bodies.
The respiratory system is focused on respiration or breathing. When you breathe the air out or in you are using lots of organs, muscles, etc. The different parts of our respiratory system are nose, mouth, nasal passage, epiglottis, larynx, voice box, vocal cords, trachea, lungs, bronchial tube, bronchus, bronchi, bronchioles, alveoli, and the diaphragm. We already know about inhalation in the respiratory system but what about exhalation? When we exhale the carbon dioxide comes from the blood and enters the alveoli. Then the carbon dioxide travels through all the tubes in our lungs and up our windpipe/trachea. Next the air comes out past the epiglottis and out our nose or mouth. Overall the respiratory system is a very important and kind of complicated system.
Digestive System:
The digestive system is a very important part of our body. We need the digestive system because the digestive system filters out the fuel for our body: nutrients. The digestive system breaks down food and takes out the nutrients. The nutrients enter the bloodstream and have to be delivered to all of your cells. The digestive system has two ways to digest food mechanical digestion and chemical digestion. Mechanical digestion is like your teeth grinding and ripping the food up. Chemical digestion is like your stomach acids breaking down the food. Our digestive system has many important parts and without them our digestive system and our body wouldn’t be able to function properly. Digestion definitely has more to it than just eating food than pooping it out!
The mouth is the first part of the digestive system where the food begins to get broken down. In your mouth the food is broken chemically and mechanically by your saliva and teeth. Your teeth break the food down into smaller bits by mechanical digestion. Your canines tear and rip the food while the molars grind the food. Your saliva however use chemical digestion to break down and soften the food. Saliva has an enzyme called ptyalin that breaks down starches making the food mushy and easier to swallow. Once the food is broken down by the teeth and saliva the tongue uses its papillae to grip the food. Then the tongue rolls up the food and sends it to the back of your throat to the esophagus. The food is now called bolus because the food is in a ball which in latin is bolus. The bolus is a soft, flexible, ball of food and it goes down your esophagus.
The next part of the digestive system comes after food starts coming down the esophagus. The esophagus is a muscular tube that brings the food from your mouth down to your stomach. The esophagus pushes food down to the stomach. When the bolus gets to the end of the esophagus a little door opens lets the bolus in and traps it inside the stomach. The esophagus uses a muscle contraction called peristalsis which is a wave like movement to move the bolus down the esophagus. Peristalsis is the reason you can eat upside down because you don’t need gravity for peristalsis to work. This system doesn’t always work though like in the case of a contraction in your intestines. When there is a contraction in your intestines something called reverse peristalsis happens. Reverse peristalsis is when the food comes back up the esophagus something we know as vomiting. Now the bolus has entered the stomach.
Your stomach is a J shaped organ that can expand when it has food in it. The stomach breaks down the food further and churns it. The stomach contains enzymes that help break down the food. In addition to breaking down the food the digestive juices/enzymes also help kill any bacteria that may be on your food. Now that the food has been churned in your stomach it is a thick liquid called chyme. There is a tube at the outlet of the stomach called the pylorus where the chyme is stored until it is the correct consistency to enter the small intestine.
The small intestine continues to break down the food by absorbing the nutrients from the food. The small intestine doesn’t have flat walls the walls are wavy so the area of the inside of small intestine is very large. The small intestine is actually way longer than the large intestine it just has a smaller circumference. The small intestine has villi which are like little fingers that absorb the nutrients. Once the villi have the nutrients they carry them into the bloodstream. The small intestine absorbs 90% of the nutrients. The small intestine can’t break down the food alone it needs help from the pancreas.
The pancreas is a gland that is located behind your stomach that assists the small intestine with digestion. The pancreas sends pancreatic enzymes into the small intestine and this helps in the process of breaking down the food. The pancreatic enzymes help to speed up the process of breaking down the food. The enzymes mainly break down fats, proteins, and carbohydrates but also help neutralize stomach acids. The pancreas and pancreatic enzymes are crucial to digestion of food inside the small intestine. Now that the pancreatic enzymes have broken down the food in the small intestine the remaining food needs help from the liver.
The liver has to process the nutrients that have been absorbed by the small intestine. The liver doesn’t work alone it has help from the gallbladder and bile. Bile is a fluid that assists to break down fats in your liver. Although bile is made in the liver bile is actually stored in the gallbladder. The gallbladder is a pouch right under the liver that stores all the bile the liver has produced. Before you have eaten the gallbladder is big and full of bile it can be as large as a pear. After you eat the bile has been used to aid in digestion so the gallbladder with nothing to hold is flattened.
All of the remaining food that didn’t get sent to the liver goes on to the large intestine. The large intestine isn’t infact larger in length than the small intestine just a larger circumference. The large intestine take any remaining liquid and absorbs it. When the liquid is absorbed it has to enter your bloodstream through the walls of your small intestine. The waste now free of any liquids hardens and is ready to exit your body we now call it faeces or poop.
The last step to the digestive system is the faeces exiting through your anus. Your anus consists of your pelvic muscles and sphincters and your sphincters make sure you don't poop your pants. The internal sphincters are tight almost all of the time like when you are asleep or when you aren't aware of your faeces. Other times like when you are dashing to find the nearest restroom you have to rely on you external sphincters. Once you make it to the bathroom your sphincters loosen up and you poop. Pooping is the final step in digestion and then you are finished digesting until your next meal.
The digestive system is important to our bodies because it helps find and transport our fuel nutrients to cells all around our body. It is interesting to learn not only how the parts of our digestive system work together but also how mechanical and chemical digestion work together. Did you know diarrhea happens when the digestive system doesn't work properly the food just go straight through your digestive system without being processed?! Some people think that digestion is all about pooping but they're wrong. Pooping is just the waste we have to get rid of after we take all the good stuff out of the food. That brings us to the digestive systems actual purpose it is to filter out all the nutrients and proteins, vitamins, good fats etc. from your food. Your digestive system is very important from helping your body function to giving your cells nutrients and vitamins.
Nervous System:
The nervous system is very important because it tells your body what to do. The nervous system is like the control center and your brain is the hub it registers everything you touch, taste, feel, hear, and see. Your nervous system is quite amazing it has to send messages to places it has to control. Simple things such as eating a cookie take a lot more than just grabbing it. Your nervous system is truly spectacular and is more complex than you think.
Your nervous system controls all of your movement and senses. The brain is the boss of the nervous system and your entire body. The brain is a gray, mushy lump but it is quite amazing. Your brain is made up of about 100 million nerve cells each, cell is connected to 10,000 other cells! Your brain controls everything you do even when you are asleep. The cerebrum is the biggest part of the brain and one of the most important. The cerebrum controls logic, planning, memory, and registers sensory. Another key part of your brain is the cerebellum. Although the cerebellum doesn’t fully control movement it contributes to coordination, precision, posture, and accurate timing. The cerebellum helps you perform smooth muscular movements. The medulla oblongata or the brainstem is key in blood circulation, respiration, and can even help a little bit in digesting food! Every sensory and motor nerve connection has to go through the medulla. The brain can’t send the message without nerves though!
Nerves are bundles of axons in charge of sending messages to the parts of your body. Nerves use electrical signals called nerve impulses to send the messages. Sensory nerves tell the brain what you are touching, tasting, hearing, smelling, and seeing these are your senses. Motor nerves help the brain control our muscles and their movement. The motor nerves however control all voluntary muscles while the involuntary muscles run on different system. The motor nerve signals have to be carried through the spinal cord which is a long bundle of neurons. The spinal cord also receives information from joints, muscles, and skin.
Neurons are a single axon or a single nerve cell that send electrochemical signals. However unlike nerves, which are only found in the central nervous system, neurons are in the central nervous system, spinal cord, and brain. Synapses are gaps between neurons that form between two neurons or a neuron and effector cell. When a neuron sends neurotransmitters to send information to another neuron it flows across a synapse. Neurons aren’t really sending and receiving neurotransmitters alone. There are branches of the neuron called dendrites which have little dendritic spines on them. The dendrites have to detect the information with their dendritic spines. At the end of the dendrites there is a thing called an axon which sends a electrochemical message to other neurons, muscles and glands. Axon’s messages are picked up by the dendrites.
Your brain, spinal cord, nerves, and neurons make up your nervous system which is the control center for your entire body! Your brain is the center of it all interpreting all the information you take in and making decisions to keep you safe. Your spinal cord carries messages to every part of the body. Your nerves and neurons are different but both have to send important messages. The nervous system may be the final paper but it is just as important as any other system.
In conclusion, the human body has many systems that each work hard to do specific jobs to benefit our bodies work together successfully to ensure our well-being. The skeletal provides support, protection, and structure while the muscular system allows us to move, breath, and digest food. The circulatory system transports oxygen and nutrients to the cells of our body while getting rid of waste products and the respiratory system swaps out the oxygen and carbon dioxide. Finally the digestive system converts food into energy while the nervous system uses that energy to make decisions and maintain memories. I appreciate the time you took to read these essays and hope that you learned something valuable. So the next time you move a muscle or take in a breath, I hope you’ll think about how impressive our human body really is!
Muscular System:
The muscular system helps the human body move around and have fun. Let’s say you want to move your arms around, eat a sandwich, or run, you use muscles! They are many different types of muscles they all serve different purposes (e.g. movement, pumping blood, and dilating your pupils. Some of these purposes are controlled by us, while others are controlled automatically by the muscle cell or the brain.
There are two types of categories of muscles in the human body: voluntary and involuntary. Voluntary muscles are muscles that we have control over. They are the muscles that control body’s movements and are attached to bones. Skeletal muscles are the only type of voluntary muscles in our body. They pull on bones to cause us to move. Skeletal muscles never push, they only pull, and that’s why they are nearly always found in pairs. One example of this is the biceps and triceps that are located in our upper arms. When the biceps want to the lower arm up, they contract or shrink, while triceps relax or expand. When the the triceps want to pull the arm down, they contract while the biceps relax. This is an example of a pair of muscles working together. But those muscles wouldn’t be able to do any of this without tendons connecting them to the bones that they move! Tendons are flexible bands of tissue that blend into bones and enable them to move the move the bones that they are supposed to move. Although skeletal muscles are the only type of voluntary muscles, there are two different types of involuntary muscles!
Unlike voluntary muscles, involuntary muscles do things automatically without us knowing it. There are two examples of involuntary muscles. They are cardiac muscle and smooth muscle. Cardiac and smooth muscles are similar because they work automatically, by themselves. Cardiac muscles are muscles,are muscles that are only found in our heart, and are responsible for pumping blood throughout our body. They work without us thinking about them, and they contract and relax throughout our entire lives. Smooth muscles are found inside your organs (e.g. intestines, esophagus, stomach, and bladder) and help move throughout our body. Smooth muscles can also be found in your your eyes and your blood vessels. Smooth muscle cells look like on big cell, but are actually a bunch of smaller, smooth cells all grouped together (unlike strained cells.) So clearly, there are many types of involuntary muscles in our body that do things we had no idea about. Including important tasks like pumping blood and digestive food!
The muscular system is a powerful system that allows us to move, convert food into energy, and circulate blood throughout our body. Our muscles make up over half of our body weight and give or body shape. In the next essay, learn how some of these muscles move blood throughout our body in order to deliver oxygen to all of our cells.
Circulatory System:
Your Circulatory System is in charge of circulating blood throughout your body hence the name circulatory system. Your circulatory system delivers blood with oxygen in it called oxygenated blood to all of your cells and brings waste rich blood, deoxygenated blood back to you lungs to breathe out. Your blood cells carry the nutrients, oxygen, and hormones but your blood flows through blood vessels which carry the blood cells to their destination. It’s all like a cycle your lungs breathe in oxygen the blood cells are oxygenated then they flow through the heart which pump them out in your arteries which carry them all over your body. Next the waste rich blood flows back in your veins to your heart where they get pumped back to your lungs to breathe out the waste and collect oxygen, and back through the heart and into the arteries. So as you can see your Circulatory System is an essential part of your life and has a lot to discover about it.
Your Circulatory System is what makes your heart pump blood and keeps your body going. Your blood is like a transport system delivering oxygen and nutrients to your cells and taking waste away. But that’s not all your blood is in charge of! Your blood is also responsible for combating against disease and helping you stay healthy. Blood’s third responsibility is to circulate heat throughout your body and keep you warm. Your blood also carries hormones throughout your body. Your blood is basically the master of multitasking balancing all the responsibilities throughout your body. You have different blood cells that make up your blood. First you have your red blood cells which are in charge of delivering oxygen and taking carbon dioxide to your lungs so they can breathe it out. There are millions of red blood cells in a drop of blood and they last 4 months before turning into new blood. Red blood cells are made in the bone marrow in lots of your bones. You also have something called White Blood cells which are the ones that help you stay healthy. White blood cells are the defenders of your body you usually have around 5,000 to 7,000 white blood cells in a milliliter of blood. When you are sick you can have around 25,000 per milliliter fighting off the bacteria. White blood cells work with something called antibodies and help combat against germs and diseases. Platelets are another part of our blood and they help plug up wounds. When you get hurt your platelets go and stick to stop the blood and they attract other platelets. The scab you get after you get a cut is actually platelets once they harden! Plasma makes up about half of your blood it is a liquidy yellow substance. Plasma carries around nutrients, hormones, proteins, and cells that float in it. Your plasma takes away waste and is made in the liver. Clearly your blood has many different interesting and complex parts.
Your blood is definitely important but what does it flow through? Why blood vessels of course! Blood vessels are the highways going through your body routing your blood to where they need to be. Blood vessels may be tiny but that doesn’t mean they aren’t mighty. Did you know that if you took all the blood vessels out of a kid they would be 60,000 miles long in adults they are 100,000 miles long! There are three kinds of blood vessels: Arteries, Veins, and Capillaries. Arteries carry oxygenated blood away from the heart. Arteries are hard on the outside but have a softer muscle inside to move the blood around your body. The arteries have to be very thick to withstand the pressure from the heart pumping really hard. The arteries get smaller and smaller until they turn into capillaries. Capillaries are the things that connect arteries to veins. The arteries deliver the oxygenated blood to the capillaries. Next the capillaries deliver waste rich blood to the veins. Veins carry the waste rich blood back to the heart. Veins aren’t as strong as arteries because they don’t have to withstand the pressure from the heart sending out blood. Veins, unlike arteries, have valves that make sure the blood is only flowing in one direction arteries don’t need valves because the heart pumps very hard so the blood only flows where the heart pushes it. Valves also help the blood come back to the heart against gravity! Now you know just how important your blood vessels are they help guide the blood to where it needs to be.
Your heart is the last part off the transport system we have our train the blood, our track the blood vessels, and last we have the station our heart. Your heart is seated in between your lungs and it serves to deliver your blood, which holds many nutrients along with oxygen that goes to every organ, tissue, and cell in your body. You need your heart to deliver oxygen and remove waste which would otherwise become dangerous. Your heart is constantly pumping new blood out to keep you alive. Your heart has four different chambers that work together the right atrium, left atrium, right ventricle, and left ventricle. Blood is pushed from the two atriums into both ventricles. Valves open between them making sure the blood only flows one way. Your left atrium receives oxygenated blood from the lungs and then sends it over to the left ventricle. Your left ventricle gets the blood from the left atrium and then has to pump the blood out to your entire body. You left ventricle is the thickest of any of the four chambers! Next we have your right atrium which receives deoxygenated blood. Then the right atrium sends the blood into the right ventricle. The right ventricle gets the blood and sends it to the lungs. The blood is sent to the lung so the waste can be breathed out and the blood will get oxygenated again. Your circulatory system is like a big loop with your heart in the middle, sending deoxygenated blood out taking new oxygenated blood back all in a big circle happening again and again always beating until you die.
You learned your Circulatory system is important it keeps you living because without your circulatory system your cells wouldn’t get oxygen and they would die. Your Circulatory System harmonizes perfectly from the blood, blood vessels, and heart working together to your four chambers working together. Your circulatory system definitely has to work hard but you don’t your heart is an involuntary muscle so your heart pumps without you even thinking about it! The Circulatory system is amazing and it is definitely interesting with all of its different parts there is so much to learn. We need another system to oxygenate our blood called the circulatory system.
Respiratory System:
The respiratory system is in charge of breathing but it also gives you the ability to make noise and smell things. The respiratory system has many parts but here are some of the main parts the nose, trachea, bronchi, lungs, alveoli, and the diaphragm. The process of breathing starts when air comes in your nose and the air is filtered. Then the air has to pass by that flap of cartilage in the back of your throat. Then the air passes through a series of tubes and then the oxygen enters your blood and carbon dioxide gets breathed back out into the air. The respiratory system has a lot more to it than just breathe in then breathe out.
The respiratory system starts with taking in air through the mouth or nose. When you take air through your mouth or nose it makes the air warm and wet because cold dry air irritates the lungs. In both the nose and mouth the air becomes warm and wet. In the nasal passage there are little tiny hairs called cilia and mucus that trap any pollen, dust, and mold before they can get to the lungs. The nasal passage or cavity does this because if the air going to the lungs is dry, cold, and filled with dust particles it will irritate the lungs. After the air passes through your nasal passage it has to get past the epiglottis. The epiglottis is a flap of cartilage that flops around in front of your windpipe. Without the epiglottis whenever you ate food or drank you would choke and die. The Larynx known as the voice box is home to the vocal chords and is involved in breathing, sound production, sound amplification, and and protecting the trachea. The Larynx connects the Pharynx and Trachea and allowing air though and keeping food and drink out. The vocal folds also known as vocal cords are set of twin mucous membranes. The air that you take in vibrates the vocal folds and makes the noise that ables you to speak and sing. Your voice box makes sure that there is a safe passageway for the air to go through. The next part of your body the air travels through is the trachea. The trachea commonly referred to as the windpipe is what connects the larynx to the bronchial tubes. The trachea is an essential part of the respiratory system and helps out delivering air to the lungs. Now the air reaches the lungs but it doesn’t stop there.
The air is now inside an important organ the lungs. The lungs main purpose is to help oxygen enter your bloodstream and carbon dioxide out of your body. Your lungs are important but they don’t do the actual putting oxygen in red blood cells they just help. After the air comes out of the trachea into the bronchial tubes which connect to the top part of your lungs known as the hilum. The bronchial tubes let air in and out of your lungs through the trachea. One bronchial tube is called bronchus and there are two, one for each lung. The bronchial tubes bring air from the trachea to the bronchi. The bronchi are the main passageways that bring air through the lungs. The bronchi are just the bronchial tubes getting smaller and going deeper into your lungs. When our bronchi split apart we get the bronchioles. Our bronchioles are the last airway the air has to pass through before all the real action happens. The alveoli are the little air sacs at the very end of the bronchioles. Even though they are tiny the alveoli do a lot of hard work. The alveoli are grouped together in clusters instead of being on their own. There are millions of alveoli in your body they take up a surface area of about 70 meters squared, and if they could be stretched out they would cover an entire tennis court. The gas exchange takes place in the alveoli it swaps carbon dioxide and oxygen. The carbon dioxide in the red blood cells has to go into the alveoli while the oxygen has to go in the red blood cells. What happens is the oxygen and carbon dioxide go through the alveoli walls, and then the oxygen goes into the capillaries and oxygenates your red blood cells. The carbon dioxide goes into the alveoli and then up further to the bronchioles. The carbon dioxide has to go in the same route as the oxygen came down in just reverse order. That may sound like that is all there could be in the respiratory system but there is one other essential part of the respiratory system. The next part of the respiratory system is the diaphragm which is a muscle located underneath the lungs. Without the diaphragm we wouldn’t be able to breathe. When the diaphragm contracts you breath in, and when the diaphragm relaxes you breathe out. Our diaphragm is an important part of our respiratory system. The respiratory system as you saw is a little confusing but very important to our bodies.
The respiratory system is focused on respiration or breathing. When you breathe the air out or in you are using lots of organs, muscles, etc. The different parts of our respiratory system are nose, mouth, nasal passage, epiglottis, larynx, voice box, vocal cords, trachea, lungs, bronchial tube, bronchus, bronchi, bronchioles, alveoli, and the diaphragm. We already know about inhalation in the respiratory system but what about exhalation? When we exhale the carbon dioxide comes from the blood and enters the alveoli. Then the carbon dioxide travels through all the tubes in our lungs and up our windpipe/trachea. Next the air comes out past the epiglottis and out our nose or mouth. Overall the respiratory system is a very important and kind of complicated system.
Digestive System:
The digestive system is a very important part of our body. We need the digestive system because the digestive system filters out the fuel for our body: nutrients. The digestive system breaks down food and takes out the nutrients. The nutrients enter the bloodstream and have to be delivered to all of your cells. The digestive system has two ways to digest food mechanical digestion and chemical digestion. Mechanical digestion is like your teeth grinding and ripping the food up. Chemical digestion is like your stomach acids breaking down the food. Our digestive system has many important parts and without them our digestive system and our body wouldn’t be able to function properly. Digestion definitely has more to it than just eating food than pooping it out!
The mouth is the first part of the digestive system where the food begins to get broken down. In your mouth the food is broken chemically and mechanically by your saliva and teeth. Your teeth break the food down into smaller bits by mechanical digestion. Your canines tear and rip the food while the molars grind the food. Your saliva however use chemical digestion to break down and soften the food. Saliva has an enzyme called ptyalin that breaks down starches making the food mushy and easier to swallow. Once the food is broken down by the teeth and saliva the tongue uses its papillae to grip the food. Then the tongue rolls up the food and sends it to the back of your throat to the esophagus. The food is now called bolus because the food is in a ball which in latin is bolus. The bolus is a soft, flexible, ball of food and it goes down your esophagus.
The next part of the digestive system comes after food starts coming down the esophagus. The esophagus is a muscular tube that brings the food from your mouth down to your stomach. The esophagus pushes food down to the stomach. When the bolus gets to the end of the esophagus a little door opens lets the bolus in and traps it inside the stomach. The esophagus uses a muscle contraction called peristalsis which is a wave like movement to move the bolus down the esophagus. Peristalsis is the reason you can eat upside down because you don’t need gravity for peristalsis to work. This system doesn’t always work though like in the case of a contraction in your intestines. When there is a contraction in your intestines something called reverse peristalsis happens. Reverse peristalsis is when the food comes back up the esophagus something we know as vomiting. Now the bolus has entered the stomach.
Your stomach is a J shaped organ that can expand when it has food in it. The stomach breaks down the food further and churns it. The stomach contains enzymes that help break down the food. In addition to breaking down the food the digestive juices/enzymes also help kill any bacteria that may be on your food. Now that the food has been churned in your stomach it is a thick liquid called chyme. There is a tube at the outlet of the stomach called the pylorus where the chyme is stored until it is the correct consistency to enter the small intestine.
The small intestine continues to break down the food by absorbing the nutrients from the food. The small intestine doesn’t have flat walls the walls are wavy so the area of the inside of small intestine is very large. The small intestine is actually way longer than the large intestine it just has a smaller circumference. The small intestine has villi which are like little fingers that absorb the nutrients. Once the villi have the nutrients they carry them into the bloodstream. The small intestine absorbs 90% of the nutrients. The small intestine can’t break down the food alone it needs help from the pancreas.
The pancreas is a gland that is located behind your stomach that assists the small intestine with digestion. The pancreas sends pancreatic enzymes into the small intestine and this helps in the process of breaking down the food. The pancreatic enzymes help to speed up the process of breaking down the food. The enzymes mainly break down fats, proteins, and carbohydrates but also help neutralize stomach acids. The pancreas and pancreatic enzymes are crucial to digestion of food inside the small intestine. Now that the pancreatic enzymes have broken down the food in the small intestine the remaining food needs help from the liver.
The liver has to process the nutrients that have been absorbed by the small intestine. The liver doesn’t work alone it has help from the gallbladder and bile. Bile is a fluid that assists to break down fats in your liver. Although bile is made in the liver bile is actually stored in the gallbladder. The gallbladder is a pouch right under the liver that stores all the bile the liver has produced. Before you have eaten the gallbladder is big and full of bile it can be as large as a pear. After you eat the bile has been used to aid in digestion so the gallbladder with nothing to hold is flattened.
All of the remaining food that didn’t get sent to the liver goes on to the large intestine. The large intestine isn’t infact larger in length than the small intestine just a larger circumference. The large intestine take any remaining liquid and absorbs it. When the liquid is absorbed it has to enter your bloodstream through the walls of your small intestine. The waste now free of any liquids hardens and is ready to exit your body we now call it faeces or poop.
The last step to the digestive system is the faeces exiting through your anus. Your anus consists of your pelvic muscles and sphincters and your sphincters make sure you don't poop your pants. The internal sphincters are tight almost all of the time like when you are asleep or when you aren't aware of your faeces. Other times like when you are dashing to find the nearest restroom you have to rely on you external sphincters. Once you make it to the bathroom your sphincters loosen up and you poop. Pooping is the final step in digestion and then you are finished digesting until your next meal.
The digestive system is important to our bodies because it helps find and transport our fuel nutrients to cells all around our body. It is interesting to learn not only how the parts of our digestive system work together but also how mechanical and chemical digestion work together. Did you know diarrhea happens when the digestive system doesn't work properly the food just go straight through your digestive system without being processed?! Some people think that digestion is all about pooping but they're wrong. Pooping is just the waste we have to get rid of after we take all the good stuff out of the food. That brings us to the digestive systems actual purpose it is to filter out all the nutrients and proteins, vitamins, good fats etc. from your food. Your digestive system is very important from helping your body function to giving your cells nutrients and vitamins.
Nervous System:
The nervous system is very important because it tells your body what to do. The nervous system is like the control center and your brain is the hub it registers everything you touch, taste, feel, hear, and see. Your nervous system is quite amazing it has to send messages to places it has to control. Simple things such as eating a cookie take a lot more than just grabbing it. Your nervous system is truly spectacular and is more complex than you think.
Your nervous system controls all of your movement and senses. The brain is the boss of the nervous system and your entire body. The brain is a gray, mushy lump but it is quite amazing. Your brain is made up of about 100 million nerve cells each, cell is connected to 10,000 other cells! Your brain controls everything you do even when you are asleep. The cerebrum is the biggest part of the brain and one of the most important. The cerebrum controls logic, planning, memory, and registers sensory. Another key part of your brain is the cerebellum. Although the cerebellum doesn’t fully control movement it contributes to coordination, precision, posture, and accurate timing. The cerebellum helps you perform smooth muscular movements. The medulla oblongata or the brainstem is key in blood circulation, respiration, and can even help a little bit in digesting food! Every sensory and motor nerve connection has to go through the medulla. The brain can’t send the message without nerves though!
Nerves are bundles of axons in charge of sending messages to the parts of your body. Nerves use electrical signals called nerve impulses to send the messages. Sensory nerves tell the brain what you are touching, tasting, hearing, smelling, and seeing these are your senses. Motor nerves help the brain control our muscles and their movement. The motor nerves however control all voluntary muscles while the involuntary muscles run on different system. The motor nerve signals have to be carried through the spinal cord which is a long bundle of neurons. The spinal cord also receives information from joints, muscles, and skin.
Neurons are a single axon or a single nerve cell that send electrochemical signals. However unlike nerves, which are only found in the central nervous system, neurons are in the central nervous system, spinal cord, and brain. Synapses are gaps between neurons that form between two neurons or a neuron and effector cell. When a neuron sends neurotransmitters to send information to another neuron it flows across a synapse. Neurons aren’t really sending and receiving neurotransmitters alone. There are branches of the neuron called dendrites which have little dendritic spines on them. The dendrites have to detect the information with their dendritic spines. At the end of the dendrites there is a thing called an axon which sends a electrochemical message to other neurons, muscles and glands. Axon’s messages are picked up by the dendrites.
Your brain, spinal cord, nerves, and neurons make up your nervous system which is the control center for your entire body! Your brain is the center of it all interpreting all the information you take in and making decisions to keep you safe. Your spinal cord carries messages to every part of the body. Your nerves and neurons are different but both have to send important messages. The nervous system may be the final paper but it is just as important as any other system.
In conclusion, the human body has many systems that each work hard to do specific jobs to benefit our bodies work together successfully to ensure our well-being. The skeletal provides support, protection, and structure while the muscular system allows us to move, breath, and digest food. The circulatory system transports oxygen and nutrients to the cells of our body while getting rid of waste products and the respiratory system swaps out the oxygen and carbon dioxide. Finally the digestive system converts food into energy while the nervous system uses that energy to make decisions and maintain memories. I appreciate the time you took to read these essays and hope that you learned something valuable. So the next time you move a muscle or take in a breath, I hope you’ll think about how impressive our human body really is!
Works Cited
- "5 Functions of Respiratory System." 5 Functions of Respiratory System. N.p., n.d. Web. 28 Mar. 2016.
- "Anatomy Of The Respiratory System." Adrenal Fatigue Solution. N.p., n.d. Web. 28 Mar. 2016.
- "Anatomy Of The Respiratory System." Adrenal Fatigue Solution. N.p., n.d. Web. 28 Mar. 2016.
- "Article: Your Nervous System Print." Your Nervous System. N.p., n.d. Web. 28 Mar. 2016.
- Bargar, R., and Jessica Seminara. WiseGeek. Conjecture, n.d. Web. 28 Mar. 2016.
- "Bile: MedlinePlus Medical Encyclopedia." U.S National Library of Medicine. U.S. National Library of Medicine, n.d. Web. 28 Mar. 2016.
- "Bile." Wikipedia. Wikimedia Foundation, n.d. Web. 28 Mar. 2016.
- "Biology for Kids." : Nervous System in the Human Body. N.p., n.d. Web. 28 Mar. 2016.
- "Biology for Kids." : Nervous System in the Human Body. N.p., n.d. Web. 28 Mar. 2016.
- "Biology for Kids." : Nervous System in the Human Body. N.p., n.d. Web. 28 Mar. 2016.
- Blake, Chris. "Four Main Parts of a Skeletal System." EHow. Demand Media, n.d. Web. 16 Mar. 2016.
- "Blood." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 16 Mar. 2016.
- "Bones, Muscles, and Joints." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 16 Mar. 2016.
- "Bones, Muscles, and Joints." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 16 Mar. 2016.
- "Bones, Muscles, and Joints." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 16 Mar. 2016.
- "Bones, Muscles, and Joints." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 16 Mar. 2016.
- "Brain Stem." Brain Stem. N.p., n.d. Web. 28 Mar. 2016.
- "Bronchi." Function, Definition & Anatomy. N.p., n.d. Web. 28 Mar. 2016.
- "Cardiovascular System." InnerBody. N.p., n.d. Web. 28 Mar. 2016.
- "Cerebellum." Function, Anatomy & Definition. N.p., n.d. Web. 28 Mar. 2016.
- "Cerebrum." InnerBody. N.p., n.d. Web. 28 Mar. 2016.
- "Circulatory System - By KidsBiology.com." Circulatory System - By KidsBiology.com. N.p., n.d. Web. 28 Mar. 2016.
- "Circulatory System - By KidsBiology.com." Circulatory System - By KidsBiology.com. N.p., n.d. Web. 28 Mar. 2016.
- "Circulatory System." Circulatory System. N.p., n.d. Web. 16 Mar. 2016.
- "Circulatory System." Circulatory System. N.p., n.d. Web. 16 Mar. 2016.
- "Circulatory System." Circulatory System. N.p., n.d. Web. 28 Mar. 2016.
- "Circulatory System." Circulatory System. N.p., n.d. Web. 28 Mar. 2016.
- "Cyh 4 Chambers." N.p., n.d. Web.
- "Definition: Pancreas." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 28 Mar. 2016.
- "A Description of Tendons, Ligaments and Muscles." LIVESTRONG.COM. LIVESTRONG.COM, 02 June 2015. Web. 16 Mar. 2016.
- "Digestive System." - Better Health Channel. N.p., n.d. Web. 28 Mar. 2016.
- "The Digestive System Diagram, Organs, Function, and More." WebMD. WebMD, n.d. Web. 28 Mar. 2016.
- "The Digestive System Diagram, Organs, Function, and More." WebMD. WebMD, n.d. Web. 28 Mar. 2016.
- "Digestive System Function & Organs | Cleveland Clinic." Digestive System Function & Organs | Cleveland Clinic. N.p., n.d. Web. 28 Mar. 2016.
- "Digestive System Function & Organs | Cleveland Clinic." Digestive System Function & Organs | Cleveland Clinic. N.p., n.d. Web. 28 Mar. 2016.
- "Digestive System." InnerBody. N.p., n.d. Web. 28 Mar. 2016.
- "Digestive System." InnerBody. N.p., n.d. Web. 28 Mar. 2016.
- "Digestive System." InnerBody. N.p., n.d. Web. 28 Mar. 2016.
- "Digestive System." InnerBody. N.p., n.d. Web. 28 Mar. 2016.
- "Digestive System." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 28 Mar. 2016.
- "Digestive System." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 28 Mar. 2016.
- "Epiglottis." Function, Pictures & Definition. N.p., n.d. Web. 28 Mar. 2016.
- "Facts About The Heart | Cool Kid Facts." Facts About The Heart | Cool Kid Facts. N.p., n.d. Web. 28 Mar. 2016.
- "The Franklin Institute." Blood Vessels. N.p., n.d. Web. 28 Mar. 2016.
- "The Franklin Institute." Blood Vessels. N.p., n.d. Web. 28 Mar. 2016.
- "The Franklin Institute." Blood Vessels. N.p., n.d. Web. 28 Mar. 2016.
- "The Franklin Institute." Blood Vessels. N.p., n.d. Web. 28 Mar. 2016.
- "The Franklin Institute." Blood Vessels. N.p., n.d. Web. 28 Mar. 2016.
- "The Franklin Institute." Blood Vessels. N.p., n.d. Web. 28 Mar. 2016.
- "The Franklin Institute." Blood Vessels. N.p., n.d. Web. 28 Mar. 2016.
- "Fun Muscle Facts for Kids - Interesting Information about Human Muscles." Fun Muscle Facts for Kids - Interesting Information about Human Muscles. N.p., n.d. Web. 16 Mar. 2016.
- "Fun Muscle Facts for Kids - Interesting Information about Human Muscles." Fun Muscle Facts for Kids - Interesting Information about Human Muscles. N.p., n.d. Web. 16 Mar. 2016.
- "Fun Muscle Facts for Kids - Interesting Information about Human Muscles." Fun Muscle Facts for Kids - Interesting Information about Human Muscles. N.p., n.d. Web. 16 Mar. 2016.
- "Fun Muscle Facts for Kids - Interesting Information about Human Muscles." Fun Muscle Facts for Kids - Interesting Information about Human Muscles. N.p., n.d. Web. 16 Mar. 2016.
- "Function of the Digestive System." EMedTV: Health Information Brought To Life. N.p., n.d. Web. 28 Mar. 2016.
- "Functions of Organs in Respiratory System | MD-Health.com." Functions of Organs in Respiratory System | MD-Health.com. N.p., n.d. Web. 28 Mar. 2016.
- "The Gallbladder (Human Anatomy): Picture, Definition, Function, and Related Conditions." WebMD. WebMD, n.d. Web. 28 Mar. 2016.
- "Gas Exchange in the Lungs." WebMD. WebMD, n.d. Web. 28 Mar. 2016.
- "Gas Exchange in the Lungs." WebMD. WebMD, n.d. Web. 28 Mar. 2016.
- "Glossary." The Respiratory System. N.p., n.d. Web. 28 Mar. 2016.
- "Heart and Circulatory System." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 16 Mar. 2016.
- "How Bones Work." HowStuffWorks. N.p., 10 Feb. 2009. Web. 16 Mar. 2016.
- "How Do Villi Affect the Absorption of Nutrients?" How Do Villi Affect the Absorption of Nutrients? N.p., n.d. Web. 28 Mar. 2016.
- "How Does Your Diaphragm Help You Breathe? - Answered by Top Doctors on HealthTap." HealthTap. N.p., n.d. Web. 28 Mar. 2016.
- "How Does Your Diaphragm Help You Breathe? - Answered by Top Doctors on HealthTap." HealthTap. N.p., n.d. Web. 28 Mar. 2016.
- "How Your Lungs Work." HowStuffWorks. N.p., 06 Oct. 2000. Web. 28 Mar. 2016.
- "Human Digestive System - EnchantedLearning.com." Human Digestive System - EnchantedLearning.com. N.p., n.d. Web. 28 Mar. 2016.
- "The Importance of Villi and the Small Intestine to the Digestion of Nutrients." The Importance of Villi and the Small Intestine to the Digestion of Nutrients. N.p., n.d. Web. 28 Mar. 2016.
- "InnerBody.com | Your Interactive Guide to Human Anatomy." Innerbody. N.p., n.d. Web. 28 Mar. 2016.
- "InnerBody.com | Your Interactive Guide to Human Anatomy." Innerbody. N.p., n.d. Web. 28 Mar. 2016.
- "A Journey Through Your Intestines." Food Matters. N.p., n.d. Web. 28 Mar. 2016.
- "Jump Rope For Heart Homework Helper." (n.d.): n. pag. Web.
- "Kids' Health - Topics - Blood - We Can't Live without It!" Kids' Health - Topics - Blood - We Can't Live without It! N.p., n.d. Web. 16 Mar. 2016.
- "Kids' Health - Topics - Blood - We Can't Live without It!" Kids' Health - Topics - Blood - We Can't Live without It! N.p., n.d. Web. 16 Mar. 2016.
- "Kids' Health - Topics - Blood - We Can't Live without It!" Kids' Health - Topics - Blood - We Can't Live without It! N.p., n.d. Web. 16 Mar. 2016.
- "Kids' Health - Topics - Blood - We Can't Live without It!" Kids' Health - Topics - Blood - We Can't Live without It! N.p., n.d. Web. 16 Mar. 2016.
- "Kids' Health - Topics - Blood - We Can't Live without It!" Kids' Health - Topics - Blood - We Can't Live without It! N.p., n.d. Web. 16 Mar. 2016.
- "Kids' Health - Topics - Blood - We Can't Live without It!" Kids' Health - Topics - Blood - We Can't Live without It! N.p., n.d. Web. 16 Mar. 2016.
- "Kids' Health - Topics - Blood - We Can't Live without It!" Kids' Health - Topics - Blood - We Can't Live without It! N.p., n.d. Web. 16 Mar. 2016.
- "KidsHealth." Your Digestive System. N.p., n.d. Web. 28 Mar. 2016.
- "KidsHealth." Your Lungs & Respiratory System. N.p., n.d. Web. 28 Mar. 2016. <https://secure02.kidshealth.org/kid/htbw/lungs.html>.
- "Learn about Your Joints - Science for Kids." Science for Kids. N.p., 22 Apr. 2015. Web. 16 Mar. 2016.
- "Learn about Your Joints - Science for Kids." Science for Kids. N.p., 22 Apr. 2015. Web. 16 Mar. 2016.
- "Left Atrium." InnerBody. N.p., n.d. Web. 28 Mar. 2016.
- "Left Ventricle." Left Ventricle Function, Definition & Anatomy. N.p., n.d. Web. 28 Mar. 2016.
- "Ligaments and Tendons: What's the Diff?" RSS. N.p., n.d. Web. 16 Mar. 2016.
- Mandal, Dr. Ananya. "The Large Intestine (Human)." News-Medical.net. N.p., 17 Nov. 2009. Web. 28 Mar. 2016.
- McMahon, Mary, and O. Wallace. "What Is a Motor Nerve?" WiseGeek. Conjecture, n.d. Web. 28 Mar. 2016.
- "Medulla Oblongata." Medulla Oblongata Function, Definition & Location. N.p., n.d. Web. 28 Mar. 2016.
- "Muscles - By KidsBiology.com." Muscles - By KidsBiology.com. N.p., n.d. Web. 16 Mar. 2016.
- "Muscles - By KidsBiology.com." Muscles - By KidsBiology.com. N.p., n.d. Web. 16 Mar. 2016.
- "Muscular System - Meat on the Bones." Biology4Kids.com: Animal Systems: Muscular System. N.p., n.d. Web. 16 Mar. 2016.
- "Muscular System." InnerBody. N.p., n.d. Web. 16 Mar. 2016.
- "MUSCULAR SYSTEM." MUSCULAR SYSTEM. N.p., n.d. Web. 16 Mar. 2016.
- "Nasal Passage." MedicineNet. N.p., n.d. Web. 28 Mar. 2016.
- "Nervous System." - Better Health Channel. N.p., n.d. Web. 28 Mar. 2016.
- "Nervous System." InnerBody. N.p., n.d. Web. 28 Mar. 2016.
- "Nervous System." InnerBody. N.p., n.d. Web. 28 Mar. 2016.
- "Nervous System." InnerBody. N.p., n.d. Web. 28 Mar. 2016.
- "Nervous System." InnerBody. N.p., n.d. Web. 28 Mar. 2016.
- "NERVOUS SYSTEM." NERVOUS SYSTEM. N.p., n.d. Web. 28 Mar. 2016.
- "Neuroscience For Kids." - Cells of the Nervous System. N.p., n.d. Web. 28 Mar. 2016.
- "Neuroscience For Kids." - Cells of the Nervous System. N.p., n.d. Web. 28 Mar. 2016.
- "Neuroscience For Kids." - Synapse. N.p., n.d. Web. 28 Mar. 2016.
- "The New International Standard Medical & Health Encyclopedia." The Mouth: Saliva, Teeth, and Tongue. N.p., n.d. Web. 28 Mar. 2016.
- "The New International Standard Medical & Health Encyclopedia." The Mouth: Saliva, Teeth, and Tongue. N.p., n.d. Web. 28 Mar. 2016.
- "The New International Standard Medical & Health Encyclopedia." The Mouth: Saliva, Teeth, and Tongue. N.p., n.d. Web. 28 Mar. 2016.
- "NIAMS Kids Pages." Healthy Muscles Matter. N.p., n.d. Web. 16 Mar. 2016.
- "Novablend System Makes Continuous PVC Compounding Possible." Plastics, Additives and Compounding 3.2 (2001): 11. Web.
- N.p., n.d. Web. <https://www.nlm.nih.gov/medlineplus/ency/anatomyvideos/000097.htm>.
- N.p., n.d. Web. <http://www.aboutgastro.com/digestive-system/conclusion-digestion>.
- N.p., n.d. Web. <http://www.bbc.co.uk/bitesize/ks3/science/organisms_behaviour_health/life_processes/revision/5/>.
- N.p., n.d. Web. <http://www.bbc.co.uk/bitesize/ks3/science/organisms_behaviour_health/life_processes/revision/5/>.
- N.p., n.d. Web. <http://www.bbc.co.uk/bitesize/ks3/science/organisms_behaviour_health/life_processes/revision/5/>.
- "Organs - Large Intestine." N.p., n.d. Web. <http://www.bbc.co.uk/science/humanbody/body/factfiles/largeintestine/large_intestine.shtml>.
- "Organs - Large Intestine." N.p., n.d. Web. <http://www.bbc.co.uk/science/humanbody/body/factfiles/largeintestine/large_intestine.shtml>.
- "Pancreas." -- Kids Encyclopedia. N.p., n.d. Web. 28 Mar. 2016.
- "Pancreas Uses and Ailments. Pancreas Information at Patient | Patient." Patient. N.p., n.d. Web. 28 Mar. 2016.
- "Parts of the Brain and Their Functions | MD-Health.com." Parts of the Brain and Their Functions | MD-Health.com. N.p., n.d. Web. 28 Mar. 2016.
- "Parts of the Nerve Cell and Their Function." Parts of the Nerve Cell and Their Function. N.p., n.d. Web. 28 Mar. 2016.
- "Parts of the Respiratory System and Their Function." Parts of the Respiratory System and Their Function. N.p., n.d. Web. 28 Mar. 2016.
- "The Respiratory System." - NHLBI, NIH. N.p., n.d. Web. 28 Mar. 2016.
- "Right Atrium." InnerBody. N.p., n.d. Web. 28 Mar. 2016.
- "Right Ventricle." Right Ventricle Function, Definition & Anatomy. N.p., n.d. Web. 28 Mar. 2016.
- "The Skeletal System." Human-kinetics. N.p., n.d. Web. 16 Mar. 2016.
- "The Skeletal System." Human-kinetics. N.p., n.d. Web. 16 Mar. 2016.
- "The Skeletal System." Human-kinetics. N.p., n.d. Web. 16 Mar. 2016.
- "Small Intestine." InnerBody. N.p., n.d. Web. 28 Mar. 2016.
- "The Stomach and Its Role in Digestion." The Stomach and Its Role in Digestion. N.p., n.d. Web. 28 Mar. 2016. <http://www.laparoscopic.md/digestion/stomach>.
- "Stomach." InnerBody. N.p., n.d. Web. 28 Mar. 2016.
- "Structure and Function of the Alveoli." Structure and Function of the Alveoli. N.p., n.d. Web. 28 Mar. 2016.
- "Structure of Bone." Bone Structure. N.p., n.d. Web. 16 Mar. 2016.
- "Structure of Bone." Bone Structure. N.p., n.d. Web. 16 Mar. 2016.
- "TeensHealth." Definition: Bronchial Tubes. N.p., n.d. Web. 28 Mar. 2016.
- "Vocal Folds, Vocal Chords, or Vocal Cords? - Choirly.com." Choirlycom. N.p., n.d. Web. 28 Mar. 2016.
- "Vocal Folds, Vocal Chords, or Vocal Cords? - Choirly.com." Choirlycom. N.p., n.d. Web. 28 Mar. 2016.
- "What Are Bones?" Kids' Health. N.p., n.d. Web. 16 Mar. 2016.
- "What Are Bronchial Tubes?" WiseGEEK. N.p., n.d. Web. 28 Mar. 2016.
- "What Are Digestive Juices?" WiseGEEK. N.p., n.d. Web. 28 Mar. 2016.
- "What Are Ligaments?" WiseGEEK. N.p., n.d. Web. 16 Mar. 2016.
- "What Are Muscles?" Kids' Health. N.p., n.d. Web. 16 Mar. 2016.
- "What Are Muscles?" Kids' Health. N.p., n.d. Web. 16 Mar. 2016.
- "What Are Muscles?" Kids' Health. N.p., n.d. Web. 16 Mar. 2016.
- "What Are Muscles?" Kids' Health. N.p., n.d. Web. 16 Mar. 2016.
- "What Are the Bronchioles?" WiseGEEK. N.p., n.d. Web. 28 Mar. 2016.
- "What Are the Intestines?" Kids' Health. N.p., n.d. Web. 28 Mar. 2016.
- "What Are Those Tiny Air Sacs in Your Lungs?" About.com Health. N.p., n.d. Web. 28 Mar. 2016.
- "What Is a Bronchus?" WiseGEEK. N.p., n.d. Web. 28 Mar. 2016.
- "What Is a Bronchus?" WiseGEEK. N.p., n.d. Web. 28 Mar. 2016.
- "What Is Peristalsis?" WiseGEEK. N.p., n.d. Web. 28 Mar. 2016. <http://www.wisegeek.org/what-is-peristalsis.htm>.
- "What Is the Function of an Axon?" WiseGEEK. N.p., n.d. Web. 28 Mar. 2016.
- "What Is the Function of the Respiratory System?" HowStuffWorks. N.p., 21 July 2011. Web. 28 Mar. 2016.
- "What Is the Nervous System?" Kids' Health. N.p., n.d. Web. 28 Mar. 2016.
- "What Is the Nervous System?" Kids' Health. N.p., n.d. Web. 28 Mar. 2016.
- "What's in a Nerve?" What's in a Nerve? N.p., n.d. Web. 28 Mar. 2016.
- "Who Am I?" How Does Your Brain Work? N.p., n.d. Web. 28 Mar. 2016.
- "Who Am I?" What Does the Central Nervous System Do? N.p., n.d. Web. 28 Mar. 2016.
- Wikipedia. Wikimedia Foundation, n.d. Web. 28 Mar. 2016.
- Wikipedia. Wikimedia Foundation, n.d. Web. 28 Mar. 2016.
- Wikipedia. Wikimedia Foundation, n.d. Web. 28 Mar. 2016.
- Wikipedia. Wikimedia Foundation, n.d. Web. 28 Mar. 2016.
- Wikipedia. Wikimedia Foundation, n.d. Web. 28 Mar. 2016.
- Wikipedia. Wikimedia Foundation, n.d. Web. 28 Mar. 2016.
- Wikipedia. Wikimedia Foundation, n.d. Web. 28 Mar. 2016.
- Wikipedia. Wikimedia Foundation, n.d. Web. 28 Mar. 2016.
- "Word! Bone Marrow." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 16 Mar. 2016.
- "Word! Cartilage." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 16 Mar. 2016.
- "Word! Epiglottis." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 28 Mar. 2016.
- "Word! Platelets." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 28 Mar. 2016.
- "Your Bones." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 16 Mar. 2016.
- "Your Bones." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 16 Mar. 2016.
- "Your Bones." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 16 Mar. 2016.
- "Your Brain & Nervous System." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 28 Mar. 2016.
- "Your Digestive System and How It Works." - Iffgd.org. N.p., n.d. Web. 28 Mar. 2016.
- "Your Digestive System." KidsHealth - the Web's Most Visited Site about Children's Health. The Nemours Foundation, n.d. Web. 28 Mar. 2016.
- "Your Intestinal Villi Work Hard Absorbing Nutrients from Your Food." About.com Health. N.p., n.d. Web. 28 Mar. 2016.
- Zimmermann, By Kim Ann. "Respiratory System: Facts, Function and Diseases." LiveScience. TechMedia Network, 11 Mar. 2016. Web. 28 Mar. 2016.