Human Body Systems

1 Circulatory: The purpose of the circulatory system is to transport blood to every part of the body. In the blood are all of the necessary gases, nutrients, and waste products; which are all transported to the necessary parts of the body. The structure of the circulatory system consists of the heart, arteries (carry blood away from the heart), veins (carry blood to the heart), capillaries (where nutrients and gas exchange occurs with the tissue), and blood.

2 Digestive: The purpose of the digestive system is to digest food and provide vital nutrients to the body. It also helps to regulate metabolism, as well as eliminate waste. The structure of the digestive system begins with the mouth. It continues with the esophagus, stomach, small intestine, large intestine, and ends with the rectum. There are several organs that associated with the digestive process. The liver, among other functions, produces bile (a digestive enzyme). The gall bladder stores bile. The pancreas also secretes digestive enzymes and hormones.

3 Nervous: The purpose of the nervous system controls all bodily activities. The structure of the nervous system is broken down into two parts: the central nervous system and the peripheral nervous system. The brain and spinal cord combines to create the central nervous system (acts as the body’s control center and coordinates body’s activities). The nerves that carry messages to and from the central nervous system to the entire body makes up the peripheral nervous system.

4 Endocrine: The purpose of the endocrine system consists of glands that secrete hormones that play a key role in the regulation of digestion, metabolism, and homeostasis. The structure of the endocrine system consists of a network of glands including the pituitary, thyroid, thymus, pancreas, testes, ovaries, adrenal, and parathyroid glands.

5 Reproductive: The purpose of the reproductive systems in male and females is to perpetuate the species through reproduction. The structure of the reproductive system is the male reproductive system consists of the testis (produce sperm), vas deferens (tube to transport sperm), urethra (continuation of vas deferens), and the penis. The female reproductive system consists of ovaries (produces eggs), the uterus, and the vagina.

6 Integumentary (skin): The purpose of the skin is it has several vital roles in maintaining equilibrium within the body. The skin is responsible for regulating your body temperature. It also serves as a protective layer to the underlying tissues. The structure of the skin is composed of two parts, the epidermis and the dermis. The epidermis is the outer, thinner portion of the skin. The dermis is the inner, thicker portion of the skin. Also associated with the skin are melanin (pigment in the skin), keratin (dead, waterproof cells), and hair follicles.

7 Skeletal: The purpose of the skeletal system is it provides a framework for a tissue of the body. It also protects the upper organs. Muscles are anchored to the bones to allow for movement. Bones also produce blood cells, and store vital minerals. The structure of the skeletal is comprised of two parts, the axial skeleton, and the appendicular skeleton. The axial skeleton is made up of the skull, the vertebral column, the ribs, and the sternum. The appendicular skeleton are the bones of the arms and legs, including the shoulders and pelvic girdle. Joints, ligaments (connect bones to bones), and tendons (connect muscles to bones) are also associated with the skeletal system.

8 Respiratory: The purpose of the respiratory system is to provide the body with oxygen, and also to dispel carbon dioxide from the body. The structure of the respiratory system is the first part of the respiratory system is the trachea, this is the passageway of air from the mouth or nasal cavity. The trachea then divides into two bronchi, with are the tubes that lead to the lungs, which then branch into bronchioles that lead to the tiny air sacs called alveoli, where gas exchange occurs with the blood.

9. Muscular : The purpose is smooth muscle allows for the contraction of organs(moves food along the intestines) and blood vessels(pushes blood through). Cardiac muscle is responsible for the pumping of the heart. Skeletal muscle allows for all movement of the body. The structure of the muscular system is there are three types of muscles: smooth, cardiac, and skeletal. Smooth muscle is found in internal organs and blood vessels. Cardiac muscle is found in the heart. Skeletal muscles are attached to bones. Muscles are also voluntary(skeletal) or involuntary(smooth and cardiac).

10 Excretory/Urinary: The purpose of the excretory system is to filter the blood and remove major waste products such as ammonia and urea. It is also responsible for regulating the PH(acidity level) of the blood. The structure of the excretory system consists of the kidneys(filters the blood), the ureters(tubes that lead from kidneys to urinary bladder), the urinary bladder(where the urine is stored), and the urethra(tubes that lead from the urinary bladder to the outside of the body).

11 Immune/Lymphatic: The purpose of the immune system is too protect the body from infections and antigens. The structure of the immune system consists of a variety of structures found throughout the body. The lymph nodes and lymph vessels are found throughout the body and help to filter out antigens(disease causing microorganisms). The tonsils, thymus gland, spleen, and bone marrow are also involved in the immune system.

All the body systems work together, otherwise the body would be dead.