The diffusion of potassium ions out of a neuron
what is repolarization?
a single motor neuron and all the muscle fibers it innervates
what is a motor unit?
the most important minerals stored in bones
what are calcium and phosphorus?
Finger-like upward projections of the dermis into the epidermis
what is dermal papillae?
Adenine's DNA base pair
what is thymine?
a mass of white lipid material that insulates the axon of a neuron
what is myelin sheath?
regulates intracellular calcium concentration
what is the sarcoplasmic reticulum?
bone-forming cells
what are osteoblasts?
Although you get wet while swimming, a tough protein within the skin prevents it from soaking up moisture like a sponge. (the name of this substance is...)
what is keratin?
The organic compounds that function in building tissues and acting as enzymes
what are proteins?
Spinal nerves exiting the cord from the level of L4 to S4
what is the sacral plexus?
The muscle tissue type that consists of single, very long, cylindrical, multinucleate cells with very obvious striations
what is skeletal muscle?
increase in bone diameter
what is appositional growth?
The layer of the serous membrane that covers an organ
what is the visceral layer?
increase the rates of chemical reactions in the body
what are enzymes?
liquid continually formed mostly by the choroid plexuses
what is cerebrospinal fluid?
the contractile unit between two Z discs
what is a sarcomere?
a joint that moves in one plane only
what is a hinge joint?
The skin that covers the palms of the hands and the soles of the feet has an extra layer of epidermis
what is status lucidum?
Ninety-six percent of the human body is composed of the elements:
what are carbon, oxygen, hydrogen, and nitrogen? (COHN)
period immediately following the firing of a nerve fiber when it cannot be stimulated
what is absolute refractory period?
the pathway used to regenerate ATP fastest during muscle activity
what is anaerobic glycolysis?
small cavities in bone tissue where osteocytes are found
what are lacunae?
Epidermal cells that are actively mitotic and replace superficial cells that are continually rubbed off are:
what are stratum basal cells?
found in fat deposits (e.g., subcutaneous tissue around organs), and serve to protect and insulate body organs; they are the major source of stored energy in the body
what are triglycerides?