Water Cooler: A refersher on the systems of the body

When it comes to learning about our bodies and how to keep them healthy, we are faced with infinite amounts of information available to us at any second. That’s why it can be helpful to bring things back to the basics.

You probably learned about the systems of the body back in grade school, and maybe more extensively in a high school or college “Biology 101” class. If it’s been a while, here’s a refresher on the main systems of the human body to help remember how they work together to keep you healthy.

The human body has 11 major systems.

The circulatory system, often referred to as or combined with the cardiovascular system, is responsible for transport of various substances throughout the body. In this system are the heart, arteries and veins which transport blood and by doing so, deliver nutrients, oxygen, hormones, carbon dioxide and blood cells to the cells of other systems. This helps those cells stabilize temperature, body pH, fight diseases and regulate the general functioning state of the body, known as homeostasis.

The digestive system breaks down food into usable nutrients as it moves through the areas of the gastrointestinal tract, like the esophagus, stomach and intestines. The organs involved in this process include the tongue, pancreas, liver, salivary glands and gallbladder.

The endocrine system sends chemical messengers (hormones) throughout the body as they are released by glands, such as the endocrine, thyroid and adrenal glands. The control center of the system is the hypothalamus, a region of the brain that regulates involuntary nervous functions and some metabolic processes.

The integumentary system is the external part of the body that separates the external environment from the internal systems of the organism. This includes the skin and appendages, as well as details like hair and nails. It helps the body regulate temperature, maintain water balance and provides a place for sensory receptors.

The immune system is a network of responses tailored to protect an organism from disease caused by various pathogens by recognizing it as something from outside the body. Part of the immune system is innate to the body and part of it adapts, learning to recognize new things, fight them and remember them next time they enter the body.

The muscular system includes the skeletal, smooth and cardiac muscles. Smooth muscles are often found on the walls of organs, like the stomach, intestines and uterus. The main function of this system is to facilitate movement, support posture and help circulate blood.

The nervous system is what allows our body to collect and sort information from the external environment. It delivers messages from the brain to other parts of the body to start the necessary actions in response.

The renal (or urinary) system filters blood in order to get rid of waste via urine. It is made up of the kidneys, ureters, bladder and urethra. It also regulates blood pressure and volume.

The reproductive system is the collection of anatomical organs that allow organisms to reproduce. A differentiated species, like humans, has significant differences between sexes which serves the biological function of providing a combination of genetic material to create optimal chances for the overall genetic fitness of the offspring.

The respiratory system is made of structures that allow for gas exchange. For humans, this generally means taking in oxygen and letting out carbon dioxide.

The skeletal system is our body’s internal framework. We’re usually born with 270 bones, and then they fuse together into only 206 bones by adulthood. Peak bone density is usually around age 21.

Because these systems work cooperatively to help your body function, they receive a lot of the same, boring, familiar health advice – regular exercise, staying hydrated and eating a variety of whole foods that helps them all run their best.