Skeletal system
The skeletal system is the framework for our bodies, consisting of the bones and bone joints. The skeletal system is important because it provides structure and shape, support for movement, and protection of our internal organs. It is also important because most bones produce blood cells. Your skull acts like a protective helmet for your brain. The spine surrounds our spinal cord, a complex bundle of nerves. Your rib cage protects your heart and lungs. Without your skeleton, your body would collapse into a heap. Bones have their own nerves and blood vessels and do various jobs such as storing body minerals. They are made of tons of living cells which help them grow and repair themselves. Bones are made up of 2 or 3 layers (it depends on if they produce blood cells and have bone marrow). They have the outer layer of hard or compact bone, which is very dense, strong, and tough. Next is the spongy bone, which is like honeycomb, lighter and slightly flexible. In the middle of some bones is a jelly-like substance called bone marrow, where new cells are constantly being produced for the blood. Your skeleton has over 200 joints. Joints are where bones come together. They allow your body to move in different ways. There are 5 types of joints: Pivot, Fixed, Ball and Socket, Hinge, and Gliding. Ligaments connect bone to bone; tendons connect muscles to bone; cartilage is cushion between your bones. Muscles connect to your skeleton and contract and move the skeleton along. Both red blood cells and white blood cells are created in our bones and work with the circulatory system. When we were embryos, we were made largely up of cartilage and were very soft. As we grew and matured, the process of ossification used calcium to create our bones. With increasing age comes loss of density and strength in the bones.
Here are some of the main parts of our skeleton:
The skeletal system is the framework for our bodies, consisting of the bones and bone joints. The skeletal system is important because it provides structure and shape, support for movement, and protection of our internal organs. It is also important because most bones produce blood cells. Your skull acts like a protective helmet for your brain. The spine surrounds our spinal cord, a complex bundle of nerves. Your rib cage protects your heart and lungs. Without your skeleton, your body would collapse into a heap. Bones have their own nerves and blood vessels and do various jobs such as storing body minerals. They are made of tons of living cells which help them grow and repair themselves. Bones are made up of 2 or 3 layers (it depends on if they produce blood cells and have bone marrow). They have the outer layer of hard or compact bone, which is very dense, strong, and tough. Next is the spongy bone, which is like honeycomb, lighter and slightly flexible. In the middle of some bones is a jelly-like substance called bone marrow, where new cells are constantly being produced for the blood. Your skeleton has over 200 joints. Joints are where bones come together. They allow your body to move in different ways. There are 5 types of joints: Pivot, Fixed, Ball and Socket, Hinge, and Gliding. Ligaments connect bone to bone; tendons connect muscles to bone; cartilage is cushion between your bones. Muscles connect to your skeleton and contract and move the skeleton along. Both red blood cells and white blood cells are created in our bones and work with the circulatory system. When we were embryos, we were made largely up of cartilage and were very soft. As we grew and matured, the process of ossification used calcium to create our bones. With increasing age comes loss of density and strength in the bones.
Here are some of the main parts of our skeleton:
- Skull- a built-in helmet for your brain
- Spinal column- backbone, made of vertebrae
- Ribs- surrounds your heart and lungs
- Sternum- connects some of your ribs in front
- Pelvis- protects digestive and reproductive organs
- Humerus, Ulna, and Radius- arm bones
- Femur, Fibula, and Tibia- leg bones
- Patella- knee cap
Muscular system
The muscular system is made up of 650 muscles that control our movement and help maintain body positions. Muscles are made of muscle fibers, which are long, thin bundles of cells. Each muscle fiber is made up of thousands of even thinner threads called fibrils. Each fibril contains two proteins- actin and myosin. Nerves in the brain and spinal cord control muscles. The muscular system produces skeletal movement, maintain posture and body position, supports soft tissues, guards entrances and exits, helps maintain homeostasis, and stores nutrient reserves. There are 3 types of muscles in the body:
The muscular system is made up of 650 muscles that control our movement and help maintain body positions. Muscles are made of muscle fibers, which are long, thin bundles of cells. Each muscle fiber is made up of thousands of even thinner threads called fibrils. Each fibril contains two proteins- actin and myosin. Nerves in the brain and spinal cord control muscles. The muscular system produces skeletal movement, maintain posture and body position, supports soft tissues, guards entrances and exits, helps maintain homeostasis, and stores nutrient reserves. There are 3 types of muscles in the body:
- Skeletal muscle- Skeletal muscles are the muscles attached to bones. They are voluntary because you can control them. Under the microscope, they look striped or striated. When the skeletal muscle contracts, it causes the bone it is attached on to move. This causes certain parts of the body to move.
- Cardiac muscle- The cardiac muscles are the heart. It constantly contracts and relaxes to pump blood around the body. It is involuntary because you do not control it.
- Smooth muscle- Smooth muscles line the stomach and intestinal walls to help move food through the digestive system. These muscles are involuntary because you cannot consciously move them.
Nervous system
The nervous system is the system of nerves and nerve centers in an animal or human, including the brain, spinal cord, and nerves. It controls body processes by using electrical impulses via a network of neurons. A neuron is a cell in the nervous system with specialized parts: dendrites as inputs, axons as outputs. Impulses jump from one neurons to the next at spaces called synapses. The central nervous system (CNS) includes the brain and the spinal cord. The peripheral nervous system includes nerve cells that carry information to or from the CNS. Nerves allow you to feel sensations. If you touch something hot with your hand, nerves send a message to your brain. Your brain quickly sends a message back to your finger telling it to stop touching the hot surface.
The Brain
The cerebrum is the largest part, divided into 4 lobes:
Spinal Cord
It is a long bundle of nerves that runs down your back. The spinal cord connects a large part of the peripheral nervous system to the brain. It also conducts motor information from the brain.
Working with other systems
The nervous system regulates and controls other systems such as excretory, digestive, reproductive, cardiovascular, and respiratory. it also directs balance and movement (skeletal and muscular).
The nervous system is the system of nerves and nerve centers in an animal or human, including the brain, spinal cord, and nerves. It controls body processes by using electrical impulses via a network of neurons. A neuron is a cell in the nervous system with specialized parts: dendrites as inputs, axons as outputs. Impulses jump from one neurons to the next at spaces called synapses. The central nervous system (CNS) includes the brain and the spinal cord. The peripheral nervous system includes nerve cells that carry information to or from the CNS. Nerves allow you to feel sensations. If you touch something hot with your hand, nerves send a message to your brain. Your brain quickly sends a message back to your finger telling it to stop touching the hot surface.
The Brain
The cerebrum is the largest part, divided into 4 lobes:
- The frontal lobe is involved with speech, thought, learning, emotion, and movement.
- The parietal lobes process sensory information such as touch, temperature, and pain.
- The occipital lobes deal with vision.
- The temporal lobes, near the temples, which are involved with hearing and memory.
Spinal Cord
It is a long bundle of nerves that runs down your back. The spinal cord connects a large part of the peripheral nervous system to the brain. It also conducts motor information from the brain.
Working with other systems
The nervous system regulates and controls other systems such as excretory, digestive, reproductive, cardiovascular, and respiratory. it also directs balance and movement (skeletal and muscular).
Immune System
The immune system is complex network of cells, tissues, organs, and the substances they produce that help the body fight infections and other diseases. Immunity means that you are protected against something. The immune system identifies a variety of threats, including viruses, bacteria, and parasites, and distinguishes them from the body's own healthy tissue. We get immunity either naturally or acquire it. Naturally means you are born with antibodies from your mom. Acquired means that over time our bodies learn to fight disease or we get vaccinated for certain illnesses.
Main parts
- Skin is the first defense mechanism for keeping toxins out of our bodies.
- Lymph nodes: Produce and store cells that fight infection and disease.
- Spleen: Contains white blood cells that fight infection and disease, controls amount of blood, disposes of old cells.
- Bone marrow: Center of bones which produces white blood cells.
- Lymphocytes: White blood cells that make antibodies that attack and kill bacteria, toxins, and cancerous cells.
- Allergies- "Allergens, or molecules with the potential to cause allergy, are everywhere in our environment. They come in the form of tree pollen, food, mold, dust mites, snake or insect venom, and animals, such as cats, dogs, and cockroaches. When the body mistakes one of these substances as a threat and reacts with an immune response, we develop an allergy. Nobody is born with allergies."-Medical News Today- Allergies: How do they develop?
- Asthma- Asthma is a chronic condition that inflames and narrows the airways in the lungs. Asthma causing wheezing, shortness of breath, and coughing. Symptoms may range from mild to severe and may happen rarely or everyday. Asthma often starts in childhood but can affect adults more severely.
- Lupus- Lupus is an autoimmune disease that occurs when your body's immune system attacks your own organs and tissue.
- Rheumatoid arthritis- Rheumatoid arthritis is an autoimmune disease in which the joints are mistakenly attacked by the immune system. This creates serious inflammation which causes the synovium (the tissue that lines the inside of a joint) to thicken. This results in swelling and pain in or around the joints.
- Cancer- Cancer is the uncontrolled growth of abnormal cells in the body.
The circulatory system allows immune cells to travel through the body. Immune cell grow in bones (Skeletal system). Movement allows immune cells to travel throughout the body (Muscular system). Parts of the digestive system including the tonsils and appendix tell if particles are harmful or not. The respiratory system is a pathway for pathogens, meaning anything that can produce disease.
Respiratory System
The respiratory system is the set of organs that allow people to breathe and exchange carbon dioxide and oxygen throughout the body. The respiratory system exchanges gases between us and our environment. It also provides us with the oxygen we need to survive and rids your body of carbon dioxide.
Parts of the Respiratory System
The circulatory system helps the respiratory system by exchanging gases with the cells, bringing oxygen from the lungs, and transporting carbon dioxide to the lungs. The nervous system helps the respiratory system by monitoring the level of gases in the blood and speeding up or slowing down breathing. The respiratory system also works to aid in the transfer of thermal energy.
The respiratory system is the set of organs that allow people to breathe and exchange carbon dioxide and oxygen throughout the body. The respiratory system exchanges gases between us and our environment. It also provides us with the oxygen we need to survive and rids your body of carbon dioxide.
Parts of the Respiratory System
- Mouth and Nose- Airway to the lungs.
- Epiglottis- Flap of cartilage at the root of the tongue, closed during swallowing to cover the opening of the trachea.
- Trachea- Windpipe; connects the pharynx and larynx to the lungs, allowing the passage of air.
- Bronchi- Main passageway to the lungs.
- Lungs- Organs situated within the rib cage, consisting of elastic sacs with branching passages into which air is drawn.
- Alveoli- Tiny sacs that allow oxygen and carbon dioxide to move between the lungs and the bloodstream.
- Diaphragm- The muscle that separates the chest (thoracic) cavity from the abdomen.
The circulatory system helps the respiratory system by exchanging gases with the cells, bringing oxygen from the lungs, and transporting carbon dioxide to the lungs. The nervous system helps the respiratory system by monitoring the level of gases in the blood and speeding up or slowing down breathing. The respiratory system also works to aid in the transfer of thermal energy.
Digestive System
The digestive system is the system of organs responsible for getting food into and out of the body and convert food into energy and basic nutrients. The digestive systems' major role in the body is to process food. To use the food we eat, our body has to break the food down into smaller molecules that it can process. It also has to excrete waste. Imagine you are eating your turkey and cheese sandwich at lunch. After you take your first bite, your salivary glands produce saliva, which is a mixture of enzymes that help break down food through chemical action. Your teeth also work to break down the sandwich, while your tongue mixes it with saliva. This turns your sandwich into a moist blob that is suitable for swallowing. As you swallow your sandwich, muscles in your throat and mouth force it into the upper esophagus. Muscles in the esophagus contract in rhythmic waves called peristalsis, which help push food down towards the stomach. When the blob reaches the lower part of the esophagus, pressure from the food signals a muscular valve to relax and let the food enter the stomach. The stomach's powerful muscles mix and churn the food into smaller pieces. Digestive glands in your stomach lining produce stomach acid and enzymes, which further break down the sandwich blob into a murky paste called chyme. Well-mixed chyme is then propelled by waves of muscle contractions through a valve called the pylorus and into the first section of the small intestine. In your duodenum or the first section of the small intestine, digestion continues as the chyme mixes with a variety of digestive juices from the pancreas, gallbladder, and liver. The pancreas produces digestive enzymes that help break down proteins, carbohydrates, and fats. Bile is produced by the liver, which helps the body digest fats. The gallbladder stores the bile. What used to be your turkey and cheese sandwich is now propelled into the second part of the small intestine, the jejunum. In the jejunum, it is further broken down into smaller nutrient molecules that can be absorbed. Next, it moves into the final portion of the small intestine called ileum. This is where almost all of the remaining nutrients are absorbed through the lining of the ileum's wall. What remains of the food when it reaches the end of the ileum is a mixture of water, electrolytes, and waste products such as dead cells and plant fibers. As the residue passes through the colon, nearly all of the water is absorbed, leaving a formed substance called stool. The stool is then passed out of the body through your anus as a bowel movement.
Parts of the digestive system
The digestive system is the system of organs responsible for getting food into and out of the body and convert food into energy and basic nutrients. The digestive systems' major role in the body is to process food. To use the food we eat, our body has to break the food down into smaller molecules that it can process. It also has to excrete waste. Imagine you are eating your turkey and cheese sandwich at lunch. After you take your first bite, your salivary glands produce saliva, which is a mixture of enzymes that help break down food through chemical action. Your teeth also work to break down the sandwich, while your tongue mixes it with saliva. This turns your sandwich into a moist blob that is suitable for swallowing. As you swallow your sandwich, muscles in your throat and mouth force it into the upper esophagus. Muscles in the esophagus contract in rhythmic waves called peristalsis, which help push food down towards the stomach. When the blob reaches the lower part of the esophagus, pressure from the food signals a muscular valve to relax and let the food enter the stomach. The stomach's powerful muscles mix and churn the food into smaller pieces. Digestive glands in your stomach lining produce stomach acid and enzymes, which further break down the sandwich blob into a murky paste called chyme. Well-mixed chyme is then propelled by waves of muscle contractions through a valve called the pylorus and into the first section of the small intestine. In your duodenum or the first section of the small intestine, digestion continues as the chyme mixes with a variety of digestive juices from the pancreas, gallbladder, and liver. The pancreas produces digestive enzymes that help break down proteins, carbohydrates, and fats. Bile is produced by the liver, which helps the body digest fats. The gallbladder stores the bile. What used to be your turkey and cheese sandwich is now propelled into the second part of the small intestine, the jejunum. In the jejunum, it is further broken down into smaller nutrient molecules that can be absorbed. Next, it moves into the final portion of the small intestine called ileum. This is where almost all of the remaining nutrients are absorbed through the lining of the ileum's wall. What remains of the food when it reaches the end of the ileum is a mixture of water, electrolytes, and waste products such as dead cells and plant fibers. As the residue passes through the colon, nearly all of the water is absorbed, leaving a formed substance called stool. The stool is then passed out of the body through your anus as a bowel movement.
Parts of the digestive system
- Mouth- The mouth is where food is partly broken down manually by chewing and by the chemical action of enzymes found in the saliva.
- Esophagus- The esophagus is a long tube that runs from the mouth to the stomach. It uses muscle contractions to force food from the throat into the stomach.
- Stomach- The stomach is a large, sack-like organ that churns the food and bathes it in a very strong gastric acid.
- Small intestine-Bile, pancreatic enzymes, and other digestive enzymes produced by the inner wall of the small intestine help in the breakdown of food.
- Large intestine - Some of the water in electrolytes are removed from the food in the large intestine. Many microbes and bacteria in the large intestine help in the digestive process.
- Rectum & Anus - Solid waste is then stored in the rectum until it is excreted via the anus.
Endocrine System |
Urinary System |
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