I. Nervous System (Central Nervous System and Peripheral Nervous System)

A. Central Nervous System (CNS)
1. consists of the brain and the spinal cord
2. the vertebrate is the master control center for almost all bodily functions
3. the spinal cord in vertebrates is single and located dorsally; it forms in the embryo as a tube with a hollow central canal (a remnant of which survives in the adult)
B. Peripheral Nervous System
1. consists of nerve fibers that relate signals between the CNS and other parts of the body (the periphery)
2. two divisions
a. Afferent: detects, encodes, and transmits peripheral signals to the CNS for processing
• peripheral signals include sensory informations from the special senses including vision, hearing, smell, taste, and touch
b. Efferent: transmits signals from the CNS to the periphery

II. Muscular System

A. Three types of muscle tissue (skeletal muscle, smooth muscle, and cardiac muscle)
B. Skeletal Muscle (voluntary or striated muscle)
1. attaches to the skeleton
2. most abundant tissue in vertebrate body
3. produces movements of the limbs, trunk, face, jaws, eyeballs, etc.
C. Smooth muscle
1. found in the walls of hollow organs and tubes (walls of digestive tract, bladder, ateries and veins)
D. Cardiac Muscle
1. found only in the walls of the heart
2. contractions are responsible for pumping blood throughout the body

III. Circulatory System

A. all vertebrates have a closed circulatory system (a circuit rigidly encompassed in well-defined channels or vessels)
B. consists of a heart and numerous arteries, capillaries and veins.
C. Arteries carry blood away from the heart, while veins carry blood toward the heart
D. Capillaries are tiny blood vessels that interconnect the arteries and the veins, and the site of material exchange between the blood and other tissue
E. Functions as the internal transport system of animals

IV. Respiratory System

A. functions by exchanging oxygen and carbon dioxide between the atmosphere and the blood
B. the system includes the respiratory system leading into the lungs, the lungs themselves, and the structures of the chest involved in producing movement of air through the airways into and out of the lungs and gills

V. Urinary System

A. consists of the kidneys, ureters, urinary bladder, and urethra
B. functions of the kidneys
1. maintaining water balance in the body
2. regulating the quantity and concentration of most ions
3. maintaining proper plasma (component of the blood) levels
4. excreting waste products of bodily metabolism
5. excreting many foreign compounds

VI. Digestive System

A. responsible for transferring nutrients, water, and electrolytes from the external environment to the internal environment
B. Components of the Digestive system and their functions
1. oral cavity (teeth): mechanical breakup of food by biting and chewing
2. stomach: stores food, churns and breaks up food, enzymatic digestion
3. small intestine: area where most food is digested and absorbed
4. large intestine: reabsorption of water

VII. Endocrine System

A. tissues responsible for producing and releasing hormones directly into the blood with no special ducts or tubes involved
B. Examples of major endocrine organs and hormones the secrete
1. Pancreas: insulin and glucagon
2. Adrenal medulla: adrenalin and noradrenalin
3. Testes: testosterone
4. Ovaries: estrogen and progesterone
5. Stomach: gastrin
C. plays an important role in internal control

VIII. Reproductive System

A. Reproduction is not essential for survival of the individual, but it is necessary for the survival of the species.
B. The system is designed to enable union of genetic material from the two sexual partners, and the female system is equipped to house and nourish the offspring to developmental point at which it can survive independently in the external environment.
C. Primary reproductive organs or gonads
1. a pair of testes in the male
2. a pair of ovaries in a female
3. in both sexes, the mature gonads perform the dual function of:
a. producing gametes (gametogenesis), spermatozoa (sperm) in the male and ova (eggs) in the female
b. secrete sex hormones, testosterone in males and estrogen and progesterone in females

IX. Immune System

A. provides protection against foreign and abnormal cells and removes cellular debris
B. Lymphoid tissues store, produce, and process leukocytes (white blood cells)
1. bone marrow
2. lymph nodes
3. tonsils
4. appendix
5. spleen
6. thymus

X. Integumentary System

A. the skin is the largest organ of the body
B. functions as an external defense mechanism against opportunistic pathogens by covering the outside of the body

XI. Skeletal System

A. Vertebrate skeletons are composed primarily of bone and/or cartilage
B. Cartilage is firm, but not as hard or as brittle as bone
1. primary component of the skeleton of an embryo in all vertebrates
2. a cartilaginous skeleton persists throughout life in some vertebrates (sharks, skates, and rays)
C. Some bones are held together at movable joints by ligaments
D. Skeletal muscles are attached to bones by means of tendons.