Organ Systems

  1. Cardiovascular or Circulatory system:Consists of heart, blood vessels, and blood.

Heart: Is made up of left and right ventricles and right and left atria (a pump)

Blood vessels: Are arteries, arterioles, capillaries, venules, and veins.

Blood: Is made up of plasma, red blood cells (erythrocytes), white blood cells

(leukocytes), and platelets (thrombocytes).

Function: Organ system in which blood vessels distribute blood under pumping action of the heart. Rapidly transports many materials to and from interstitial fluid and cells; helps stabilize pH and temperature.

  1. Lymphatic system or Immune system: Consists of lymph organs (spleen, thymus, lymph nodes) and lymph (fluid consists of white cells)

Function: Immunity; collects and returns some tissue-fluids to the blood stream; defends the body against infection and tissue damage.

  1. Digestive system: Consists of oral cavity (mouth), esophagus, stomach, small intestine, large intestine, rectum, and anus.

Function: Ingests food and water mechanically, chemically breaks down food, and absorbs small molecules into internal environment; eliminated food residues.

  1. Respiratory system: Consists of nasal cavity (nose), windpipe (trachea), and lungs (bronchus and bronchiole).

Function: Rapidly delivers oxygen to the tissue fluid that bathes all living cells; removes carbon dioxide wastes of all cells; helps regulate pH.

  1. Excretory system or Urinary system: Consists of kidneys, ureters, urinary bladder, urethra, and urine.

Function: Maintains the volume and composition of internal environment; excretes excess fluid and blood-borne wastes.

  1. Nervous system: Central nervous system: Brain and spinal cord. Peripheral nervous system: Peripheral nerves. Sense organs: Chemical sense (sense of taste, sense of smell), Mechanoreceptors (Touch, vibration, hearing and balance),photoreceptors (sense of vision), pain receptors.

Function: Detects external and internal stimulus, controls and coordinates the response to stimulus; integrates all organ system activities.

  1. Skeletal system: Bones

Function: Movement support and protects body parts; provides muscle attachment sites, produces red blood cells (bone marrow), stores calcium phosphate (hydroxyapatite), and collagen (a fibrous protein).

  1. Muscular system: Muscles

Function: Movement; moves body and its internal parts, maintains posture, generates heat by increases in metabolic activity. Muscle contracts and shortens as actin and myosin fibers get into each other.

  1. Endocrine system: Consists of glands and hormones.

Function: Hormonally controls body functions, with nervous system integrate short-term and long-term activities.

  1. Integumentary system: Consists of skin, epidermis, dermis, keratin (a fibrous protein) in hair, nails and over skin.

Function: Protects body from injury, dehydration, and some pathogens, controls its temperature, excretes certain wastes, receives some internal stimuli.

  1. Reproductive system:

Female: Produces eggs; after fertilization affords a protected, nutritive environment for the development of new individuals.

Male: Produces and transfers sperm to the female.

Hormones of both systems also influence other organ systems.

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