Body SystemsAdapted from Georgia Virtual School http://www.gavirtuallearning.org/
Integumentary• Skin is a soft outer covering of the body.• In mammals, the skin is the largest organ of the integumentary system made up of multiple layers of ectodermal tissue, and guards the underlying muscles, bones, ligaments and internal organs.• The skin forms a barrier to help keep bacteria from getting inside; this is considered the first line of nonspecific defense.• The skin is actually the largest organ in the body and is referred to as part of the Integumentary System.
Skeletal System• The Skeletal System is composed of 206 bones, connected to each other by ligaments. There are several very important functions performed by the skeletal system besides forming the framework for the body.• Support-provides internal framework that support tissues• Protection-protects soft body organs• Movement-Skeletal muscles that are attached to bones use the bones as levers to move the body.• Storage-Bone is a storehouse for minerals such as calcium• Blood Cell Formation-site of blood cell formation
Muscular System• The Muscular System is made up of over 600 muscles.• Muscle tissue is specialized with the ability to contract and relax when stimulated to do so.• Some muscles, such as those in the digestive system or the iris of the eye, are involuntary and move without conscious thought. These are referred to as smooth muscles and are usually controlled by the medulla at the base of the brain.
Nervous System• The nervous system is the master controlling, regulating and communicating system of the body. The nervous system has three overlapping functions:• Sensory input-monitor changes inside and outside the body• Integration-processes and interprets sensory input• Motor output-effects a response by activating muscles or glands• The nervous system is divided into 2 subdivisions:• central nervous system• peripheral nervous system
Central Nervous System• The Central Nervous System• The brain and spinal cord are the organs of the central nervous system. Because they are so vitally important, the brain and spinal cord, located in the dorsal body cavity, are encased in bone for protection.• The central nervous system interprets incoming sensory information and send out responses based on past experiences and current conditions.• The brain is in the cranial vault and the spinal cord is in the vertebral canal of the vertebral column. Although considered to be two separate organs, the brain and spinal cord are continuous at the foramen magnum
Peripheral Nervous System• The organs of the peripheral nervous system are the nerves and ganglia.• Nerves are bundles of nerve fibers, much like muscles are bundles of muscle fibers.• Cranial nerves and spinal nerves extend from the CNS to peripheral organs such as muscles and glands. Ganglia are collections, or small knots, of nerve cell bodies outside the CNS.• Spinal nerves carry impulses to and from the spinal cord. Cranial nerves carry impulses to and from the brain. These nerves act as communication lines by linking all the parts of the Nerve body. Citation: http://commons.wikimedia.org/wiki/File:Astrocytre.jpg
Endocrine System• The endocrine system, along with the nervous system, functions in the regulation of body activities.• The endocrine system maintains homeostasis by releasing chemicals called hormones.• This system controls growth, development, reproduction and metabolism.• The endocrine system is made up of the endocrine glands that secrete hormones. Although the endocrine glands are scattered throughout the body, they are still considered to be one system because they have similar functions, similar mechanisms of influence, and many important interrelationships.
Circulatory System• Most of the cells in the human body are not in direct contact with the external environment. The circulatory system acts as a transport service for these cells.• Two fluids move through the circulatory system: blood and lymph.• The blood, heart and blood vessels form the circulatory system.• The lymph, lymph nodes and lymph vessels form the lymphatic system.
Digestive System• When you eat foods—bread, meat, fruits, vegetables, snacks, candy, or desserts—they are not in a form that the body can readily use as nourishment.• The food and drink that you introduce into your body must be changed into smaller molecules of nutrients before they can be absorbed into the blood and carried to cells throughout the body.• Digestion is the process by which food and drink are broken down into their smallest parts so the body can use them to build and nourish cells and to provide energy.
Excretory System• Function to get rid of unwanted waste in the body• The kidneys perform the critical regulation of the bodys salt, potassium and acid content. The kidneys also produce hormones that affect the function of other organs.• The kidneys are powerful chemical factories that perform the following functions:remove waste products from the bodyremove drugs from the bodybalance the bodys fluidsrelease hormones that regulate bloodpressureproduce an active form of vitamin D thatpromotes strong, healthy bonescontrol the production of red blood cells
Reproduction- Female• The organs of the human female reproductive system work together to produce eggs and prepare the females body for the possible implantation of an embryo.• The main structures of the human female reproductive system are:• Ovaries - main female reproductive organs that store egg cells.• Fallopian tubes - the two tubes connecting ovaries to the uterus; egg is swept here during ovulation; if fertilization occurs, it occurs here.• Uterus - organ in which a fertilized egg can develop.• Endometrium - inner lining of the uterus.• Cervix - lower third of the uterus.• Vagina - canal that connects cervix to the outside of the body.
Reproduction- Male• The organs of the male reproductive system work together to produce and deliver sperm.• The primary reproductive organs of the male are the testes, or male gonads.• The testes produce sperm, an exocrine function, and they also produce and secrete testosterone, an endocrine function. The main structures of the male human reproductive system are:• Testes - internal male reproductive organs; produce testosterone, the male sex hormone, which is required for sperm production and lead to male secondary sex characteristics• Duct System – epididymis - This highly coiled tube is about 6 meters (20 feet) long and provides a temporary storage area for immature sperm. For 20 days, the sperm mature as they move through the epididymis. – Vas deferans – muscular tube that propels sperm from the epididymis to the urethra. Citation: http://commons.wikimedia.org/wiki/File:Male_reproductive_system_lateral_nolabel .png