BODY SYSTEMS

The bodies of multicellular organisms are organised into a number of systems of interconnected organs. Each body system performs a different role in the body, although some functions may overlap (eg. circulatory and cardiovascular system)

Digestive System - involved in the breakdown of food and absorption of nutrients. Consists of the mouth and teeth, oesophagus, stomach, small intestine, pancreas, liver, colon and rectum

Nervous System - involved in control and rapid reaction to stimuli. Consists of brain and spinal cord (central nervous system), nerves and receptors (peripheral nervous system)

Respiratory System - involved in gaseous exchange of oxygen and carbon dioxide. Consists of upper air passages, larynx, trachea, bronchi, bronchioles, alveoli, lungs and diaphragm

Cardiovascular System - involved in transport of substances around body. Consists of heart and blood vessels (veins, arteries, capillaries)

Excretory System - involved in removal of waste products from the blood. Consists of the kidneys, ureters, urinary bladder and urethra

Immune System - involved in the defence of the body. Consists of skin, lymph nodes, bone marrow, spleen, thymus

Endocrine System - involved in the long term maintenance and control of the body using hormones. Consists of the circulatory system and various hormone secreting organs (eg. thyroid, adrenals, pituitary, pancreas)

Reproductive System - involved in the production of new individuals. Consists of the gonads (testes and ovaries), vas deferens, prostate and penis in males; and fallopian tubes, uterus and vagina in females.

Musculo-Skeletal System - involved in the support and movement of the body. Consists of the bones of the skeleton and the muscles.

Disease states may affect any of these systems. Typically, a disease in a particular organ system adversely affects the way that system functions.

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