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Human Body

The human body is everything that makes up, well, you. What decides and regulates the physical form and function of the human body is our genetic information, however, external environments and behaviors can alter the way our body’s look and how well they function, according to Human Growth and Developments. The human body is made up of all the living and nonliving components that create the entire structure of the human organism, including every living cell, tissue and organ. On the outside human anatomy consists of the five basic parts, the head, neck, torso, arms and legs. However, beneath the skin there are countless biological and chemical interactions that keep the human body machine ticking over.

Our bodies consist of a number of biological systems that carry out specific functions necessary for everyday living.

The job of the circulatory system is to move blood, nutrients, oxygen, carbon dioxide, and hormones, around the body. It consists of the heart, blood, blood vessels, arteries and veins. According to the Cleveland Clinic, the human body’s network of blood vessels, veins and capillaries is over 60.00 miles (around 96.56 kilometres) long.

The digestive system consists of a series of connected organs that together, allow the body to break down and absorb food, and remove waste. It includes the mouth, esophagus, stomach, small intestine, large intestine, rectum, and anus. The liver and pancreas also play a role in the digestive system because they produce digestive juices filled with enzymes to break down the components of your food, such as carbohydrates, fats and proteins, according to the National Institute of Diabetes and Digestive and Kidney Diseases.

The endocrine system consists of a network of glands that secrete hormones into the blood. These hormones, in turn, travel to different tissues and regulate various bodily functions, such as metabolism, growth and sexual function, according to Johns Hopkins Medicine. For example, one of the glands in the pancreas – called the endocrine gland – releases hormones called insulin and glucagon to regulate blood sugar.

The immune system is the body’s defense against bacteria, viruses and other pathogens that may be harmful. The immune system is activated when antigens (proteins on the surface of bacteria, fungi and viruses) bind with receptors on immune cells, alerting the body to their presence and kicking the immune system into gear, according to Institute for Quality and Efficiency in Health Care (IQWiG). The system is made up of I lymph nodes, the spleen, bone marrow, lymphocytes (including B-cells and T-cells), the thymus and leukocytes, which are white blood cells.

Human Body Organ System

Human Physiology

A Brief Introduction to Physiology

Physiology is the study of normal function within living creatures. It is a sub-section of biology, covering a range of topics that include organs, anatomy, cells, biological compounds, and how they all interact to make life possible.

From ancient theories to molecular laboratory techniques, physiological research has shaped our understanding of the components of our body, how they communicate, and how they keep us alive.

Merrian-Webster defines physiology as:

“[A] branch of biology that deals with the functions and activities of life or of living matter (such as organs, tissues, or cells) and of the physical and chemical phenomena involved.”

Fast Facts on Physiology:

Here are some key points about physiology. More detail and supporting information is in the main article.