Chapter 11.3 Flashcards
1
Q
PNS is made up of?
A
myelinated neurons that transmit action potentials between body tissues and the CNS.
2
Q
The PNS includes two divisions:
A
Internal environment - sensory neurons- CNS
CNS - motor neurons - Internal environment
External Environment - sensory neurons - CNS
External environment - motor neurons - CNS
3
Q
- Sensory- Somatic Nervous System
A
- focuses on external environment
- controls voluntary (conscious) and involuntary (reflexes) skeletal muscle movement
4
Q
Autonomic nervous system
A
- focuses on internal environment and controls “automatic” functions of the body’s internal organs. This system is composed of two antagonistic subdivisions
- sympathetic system
- parasympathetic system
- hypothalamus and medulla oblongata control the autonomic system
5
Q
Sympathetic System
A
- typically activated in stressful situations and is often referred to as the fight or flight response
- neurons releases neurotransmitter- norepinephrine- has excitatory effect on target muscles
- adrenal glands triggered to secrete epinephrine & norepinephrine- hormones that activate the stress response
6
Q
Parasympathetic system
A
- activated when the body is calm and at rest. Acts to restore and conserve energy. Sometimes referred to as the rest and digest response
- neurons release neurotransmitter acetylcholine
7
Q
sympathetic system actions
A
- inhibit digestion
- converts glycogen to glucose
- relaxes sphincter
- increased heart rate
- increased blood pressure
- pupils dilate
- bronchi dilate
- decreased blood flow to skin
8
Q
Parasympathetic system action
A
- promotes digestion
- stimulates bile production
- constricts sphincter
- decreased heart rate
- decreased blood pressure
- pupils constrict
- bronchi constrict
- increased blood flow to skin
