... by electrical impulses transmitted by the nerves
, the motor nerves
and motoneurons in particular. All skeletal ... between various areas of the brain.
that control skeletal muscles in mammals ...
... Chemicals that target the activity of nerves
generally are the most rapidly acting toxins , ... and spinal cord . The PNS consists of all other nerves
and neurons that do not lie within the CNS. The large majority of what are commonly called nerves
(which are actually axonal processes of nerve ...
... called the hilus, which admits the renal artery , the renal vein , nerves
, and the ureter .
The outermost portion of the ... hilus : The opening in the middle of the concave medial border for nerves
and blood vessels to pass into the renal sinus.
renal column : The ...
... vertebrates , they are found in the brain , the spinal cord and in the nerves
and ganglia of the peripheral nervous system .
Contents ... cells in the peripheral nervous system. The myelin sheath in peripheral nerves
normally runs along the axon in sections about 1 mm long, punctuated by ...
... by light of various wavelengths, stretched, sheared or electrified (the nerves
and muscles , for example). Signal transduction mediates how cells ... mechanism underlies the action potential impulses that travel along nerves
Nuclear (or cytoplasmic) receptors are ...
... systematically rather than topographically.
Each anatomical article contains first a description of the structures of an organ or system (such as nerves
, arteries , heart , and so forth), as it is found in humans; this is followed by an account of the development (embryology) and comparative ...
... from the neuron's cell body or soma. Axons are in effect the primary transmission lines of the nervous system , and as bundles they help make up nerves
. Individual axons are microscopic in diameter--typically about one micrometre across-- but may extend to macroscopic lengths. The longest axons in ...
... opening through a bone
a broad, shallow depressed area
a long, tunnel-like Foramen , usually a passage for notable nerves
or blood vessels
a short Canal
a cavity within a cranial bone
Parts of long bones
Diaphysis , ...
Vertebrate brains receive signals through nerves
arriving from most portions of a body, interpret those signals and formulate reactions based on prior experiences and on physical needs. A similarly ...
... homeostasis. Positive feedback is less common in naturally occurring systems than negative feedback, but it has its applications. For example, in nerves
, a threshold electric potential triggers the generation of a much larger action potential . (See also leverage points .)
Areas of physiology
Physiology has several independent subdivisions. Electrophysiology deals with the operation of nerves
and muscles ; neurophysiology concerns the physiology of brains and cell physiology addresses the functioning of individual cells .
... of the cutaneous vascular areas leads to a larger flow of blood through the skin, and so tends to cool the body, and vice versa. Also the special nerves
of perspiration can increase or lessen heat loss by promoting or diminishing the secretions of the skin. There are greater difficulties in the exact ...