There are a grand total of eleven body systems. Can you name them all?
In all, the human body has 11 essential body systems. A body system is a group of organs working together to provide a specific function. Each system is important to the survival and growth of a human being. Do you know all of your systems? Give it a whirl:
- Skeletal System
The human skeleton is made out of bones that support the body and help it to move. Without bones, people would be like jellyfish and couldn’t support themselves or stand up. Adults have 206 bones in their body, and babies have more. When people grow up, their bones start to fuse together and that’s why adults have less bones than babies.
- Muscular System
The skeletal and muscular system is sometimes also referred as the musculoskeletal system because they have to work together. The muscular system lets the bones move. Any action you do, from playing piano to running has to do with your muscles. Your heart and many organs are also dependent on muscles.
- Circulatory System
The circulatory system contains all the blood and blood vessels in your body. Its job is to carry oxygen and food to other cells around your body via blood vessels. Blood goes in a big circular path-starting at the lungs to gather oxygen, and going around until it goes back to the lungs. Then the process starts over again.
- Respiratory System
The respiratory system is in charge of giving you air. The air goes in through your nose or mouth when you inhale, then down your trachea into the two lungs. Then it goes into tiny air sacs, or alveoli in the lungs. Then the oxygen is carried out to other cells by the red blood cells, and the waste gas produced, carbon dioxide, is exhaled out.
- Nervous System
The nervous system consists of the brain, the spinal cord, and nerves. This body system’s job is to control movements, keep the organs working, and control the senses. Without this body system, you couldn’t move or think or sense! You would be dead!
- Digestive System
The job of the digestive system is to digest food and release the nutrients into the bloodstream. The nutrients then go to the other cells throughout the body. Food goes in the mouth, and saliva helps break some of it down. Then, when you swallow, it goes down the esophagus to the stomach, where it gets churned into mush, then down the small and large intestines, where the nutrients get absorbed and the waste released.
- Integumentary System
The integumentary system is your skin. It is the first line of defense against germs. Your skin contains glands that produce oil to kill germs, sweat to cool you down, and also has fat, which keeps you warm. The skin is very flexible, and grows with your body.
- Endocrine System
The endocrine system tells the body how to develop. It does that by releasing hormones that contain instructions to cells about how to grow. Hormones affect organs and glands by telling them how to operate. For example, when you get hot, hormones tell the sweat glands to start sweating in order to cool you off. The nervous system and endocrine system usually work together in those cases.
- Immune System
This system is in charge of protecting your body from harmful bacteria and viruses. Namely, the white blood cells eat the germs. There are many different types of white blood cells, and they all do different jobs. The white blood cells are produced in bone marrow and are stored in the spleen. The lymphatic system is part of the immune system.
- Reproductive System
The reproductive system is how babies are born. Basically, sperm from the male swims over to the female egg. The first sperm that gets to the egg fertilizes it. After that, all other sperm are blocked from fertilizing the egg. After the egg is fertilized, the baby grows and stays in the mother’s womb for nine months and then is given birth.
- Urinary System
The urinary system is made up of the kidneys, bladder, and tubes called the ureter and urethra. Its job is to clean the blood and body of liquid wastes. The process starts at the kidneys, which filter blood. The liquids that are filtered form the urine, which travel down two sets of tubes called ureters to the bladder. The bladder acts as a storage tank that holds the urine until it is emptied. The urine goes down the urethra, another tube, and goes (hopefully) in the toilet.