nervous system
the body has connectors neurons that communicate signals throughout the body. messages are sent through nerves called neurons that are responsible for communication in the body. the nervous system controls the body's sense of smell, hearing, tasting, seeing and touching. the brain is the largest function of the nervous system.
endocrine system
the endocrine system is made from different glands in the body that are in charge of moving chemicals and hormones through the body. hormones control varies functions in the body such as growing, metabolism and moods. a gland is a bunch of cells that release chemicals. the endocrine system has an affect on nearly every cell, function and organ in the human body.
respiratory system
the respiratory system brings oxygen into the human body and gets rid of carbon dioxide. the body needs oxygen to live. the organ used in the respiratory system is the lungs. inside the lungs are tiny sacs. when the body takes in air, the lung sacs fill with air. the heart pumps blood inside the lungs and takes in oxygen and releases carbon dioxide. every breath the body takes consists of taking in oxygen and releasing carbon dioxide. your lungs and respiratory system
circulatory system
the primary job of the circulatory system is transporting materials through the body. it carries nutrients, oxygen and water to different cells in the body and removes wastes the cells create. the main parts of the circulatory system are the heart, blood, and blood vessels. the heart beats three billion times in an average life span and its primary goal is keeping the blood flowing through the body.
immune system
the immune system is made up of cells, organs, proteins and tissues that fight together to guard the human body against diseases. the skin is an organ of the immune system that keeps harmful substances out of the body and holds beneficial substances in. the immune system attacks germs and rids the body of disease. the body fights a common cold by producing more mucus through the mucous membranes which drain the germs out of the body.
muscular system
the muscular system partners with the skeletal system to the body move. the muscular tissues cool and heat the body under the skin. muscles that are not controlled are called involuntary muscles. the muscles that are controlled are the voluntary muscles. almost half the weight of the human body is made up of the skeletal system. there are approximately 650 muscles in the human body.
skeletal system
the skeletal system protects major organs throughout the body. bones are connected by cartilage, joints and ligaments. the skeletal system allows the body to move around and gives it shape. bones contain marrow inside where red and white blood cells are made and carried through the whole body by the circulatory system.
excretory system
toxins are expelled through the excretory system. the most important organs of the excretory system are the kidney, liver and skin. the liver works as a filter to catch wastes and remove them from the body. excess salt is removed out of the body by the kidneys. the skin secretes salt, water and other toxins out of the body by sweating. the excretory system is very important for keeping the body clean.
