SYSTEMS OF THE BODY

System of the body is a group of organs that work together to perform a certain task. The human body consists of many interacting systems. Each system contributes to the maintenance of homeostasis ( a physiological process by which the internal systems of the body such as blood pressure, body temperature and acid-base balance are maintained at equilibrium) of itself, other systems, and the entire body. A system consists of two or more organs, which are functional collections (aggregation) of tissue. Systems do not work in isolation, and the well-being of the person depends upon the well-being of all the interacting body systems.

There are twelve main systems of the body. The major systems of the human body are as follows: the musculoskeletal, the nervous, the circulatory, the digestive, the respiratory, the urinary, the endocrine, the reproductive and other systems.

The musculoskeletal system consists of the human skeleton (which includes bones, ligaments, tendons and attached muscles. It gives the body basic structure and the ability for movement.

The nervous system consists of the brain and spinal cord, nerves, ganglia and receptors. It is a complex information system with all the necessary means for receiving, processing, and communicating information.

The circulatory system, also called the cardiovascular system, is an organ system that permits blood to circulate and transport nutrients (such as amino acids and electrolytes), oxygen, carbon dioxide, hormones, and blood cells to and from cells in the body to nourish it and help to fight diseases, stabilizing body temperature and pH level, and maintaining homeostasis.

The human digestive system consists of a long muscular tube and several accessory organs such as the salivary glands, pancreas and gall bladder. It is responsible for food ingestion and digestion, absorption of digestion products and the elimination of undigested materials.

The respiratory system consists of the lungs, the air passages leading to them and associated structures. It brings oxygen from the air to the lungs and excretes carbon dioxide and water back into the air.

The urinary system consists of the kidneys, two ureters, bladder, and urethra. It removes water from the blood to produce urine, which carries a variety of waste molecules and excess ions and water out of the body.

The endocrine system consists of a number of glands throughout the body which produce regulatory substances called hormones. The endocrine system serves to regulate a large number of activities.

The lymphatic system is a network of organs, lymph nodes, lymph ducts, and lymph vessels that make and move lymph from tissues to the bloodstream. The lymph system is a major part of the body's immune system. It includes the tonsils, adenoids, spleen, and thymus. Lymph nodes make immune cells that help the body fight infection. They also filter the lymph fluid and remove foreign material such as bacteria and cancer cells.

Exercise 7. Answer the questions:

1. What are the 12 major body systems of the human?

2. What is the main contribution of each system?

3. What does the musculoskeletal system consist of?

4. What system helps us to receive, process, and communicate information?

5. What is the main function of the circulatory system?

6. What system is responsible for food ingestion and digestion, absorption of digestion products and the elimination of undigested materials?

7. What organs does the urinary system include?

8. What body system brings oxygen from the air to the lungs and excretes carbon dioxide and water back into the air?

9. What physiological process helps to maintain the internal systems of the body at equilibrium?

10. What does the well-being of any person depend upon?

Date: 2016-06-12; view: 7