The nervous system
The nervous system
the network of nerve cells and fibers that transmits nerve impulses between parts of the body.
What does the nervous system consist of?
central nervous system and peripheral nervous system
nerve cells
Cells that carry information in the body
Receptors
In neurons, specialized protein molecules on the postsynaptic membrane; neurotransmitters bind to these molecules after passing across the synaptic cleft.
Effectors
-produces a response e.g.muscle contracts to move hand away from stimulus or gland squeezes and releases hormone into blood.
Reflex action
An immediate response to a specific stimulus without conscious control.
;.........Synapses
Tiny spaces between neurons; the gaps between neurons are referred to as synaptic gaps.
Somatic and autonomic systems
The PNS has two groups of nerve. Somatic and autonomic. The somatic nervous system controls voluntary actions, such as using a fork. The autonomic nervous system controls involuntary actions, such as digesting food.
Autonomic divisions
parasympathetic and sympathetic
Sympathetic nervous system
the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations
Parasympathetic system
the division of the autonomic nervous system that calms the body, conserving its energy