Learning about human anatomy can be helpful for anyone wanting to maintain good health. Whether you are pursuing a nursing degree or not, learning about the human body can be fascinating. By understanding how the different systems work together to ensure that the entire body functions, it becomes clear that each system is vitally important. The body is both complex and adaptive, designed to function even under less than ideal circumstances.
The human body includes a number of complex systems that work together to maintain life. The systems include the cardiovascular, digestive, endocrine, lymphatic, muscular, nervous, reproductive, respiratory, skeletal, and urinary systems.
All of the systems of the body work together for full function. If any separate system stops working correctly, the entire body will often be in poor health.
Cells have many different jobs inside the body, many of them highly specialized, such as eliminating toxins from the body or producing enzymes and hormones.
Digestive System (PDF)
The digestive system is responsible for digesting food so the body can use it. The digestive includes not only the stomach but also the mouth, esophagus, intestines, and more.
The digestive system begins in the mouth as food is taken into the body. The esophagus transports food to the stomach, where chemicals help break down the food into fuel for the body.
As the digestive system breaks down food, it extracts nutrients the body needs to maintain health. Nutrients are absorbed into the bloodstream, where they travel throughout the body.
The pancreas is a gland that is a part of the endocrine system, responsible for controlling blood sugar levels.
Three types of muscles make up the muscular system. These types include skeletal, cardiac, and smooth muscles. Skeletal muscles are the voluntary ones attached to bones, which humans use to move and which help stabilize joints.
Movement involves the muscles, skeleton, and brain. First, the brain sends a message to a muscle. The muscle moves, which also causes the bones to move.
Skeletal muscles are the most prevalent type of muscle in the body. These muscles comprise roughly 40 percent of a person’s total body mass.
The circulatory system is the internal network that manages blood flow throughout the body. The heart beats roughly 3 billion times during an average lifetime.
An average adult person has between five and six quarts of blood. The circulatory system also moves clear lymph fluids, which help eliminate waste.
Cardiovascular System (PDF)
The cardiovascular system includes the heart, which moves blood throughout the body via vessels. Blood oxygenates the body while also delivering other substances to the cells.
Meet the Heart (video)
This video explores the heart, where it sits in the chest, and its function in the body. The heart sits between the lungs and above the diaphragm, protected by the ribs.
The Skeletal System (PDF)
The skeletal system includes 206 bones in the adult body. These bones shape and support the body, protecting organs and enabling movement through muscles.
The body needs new oxygen continuously to survive. The respiratory system is in charge of taking in oxygen and passing it to waiting cells.
The Endocrine System (PDF)
The endocrine system produces and secretes hormones, which regulate cell activity. The endocrine system is also responsible for the body’s growth and anatomy development.
Endocrine glands secrete hormones into the blood. Hormones are special signals the body uses to regulate how cells operate.
The immune system is responsible for fighting off infections in the body. This system involves white blood cells, which attack invaders that could cause illness and disease.
Lymphatic vessels, tissues, and organs defend the body against germs and other invaders to maintain health.
The Lymphatic System (PDF)
Lymph is fluid that has to be drained. The lymphatic system is responsible for draining lymph because if it is allowed to accumulate, tissues swell, which causes stress on other systems.
Capillaries connect the lymphatic and cardiovascular systems, transporting both fluids and blood throughout the body.
The nose is responsible for taking in air. The nose connects to the nasal cavity and sinuses. The roof of the nasal cavity is responsible for perceiving smells.
The nervous system includes the brain, the spinal cord, and peripheral nerves that extend out through the body. The nervous system manages all sensations, thoughts, and actions.
Think of the nervous system as the expansive communication network that manages the body’s actions.
The autonomic nervous system controls body processes like your heart rate and how fast you breathe automatically.
The parts of the male reproductive system exist primarily to make and transport sperm cells.
The parts of the female reproductive system work together to supply egg cells for fertilization and create an environment for human reproduction to occur.
The reproductive system is the only one that is vastly different for the different genders. The male and female reproductive systems have different organs with different purposes.
Urinary System (PDF)
The urinary system includes components such as the kidneys and bladder. The urinary system is responsible for eliminating metabolic waste.