PNS & autonomic nervous system Flashcards
CNS
brain, brainstem and spinal cord
PNS
nerves and ganglia outside the CNS
what does the PNS split into
- somatic nervous system
- autonomic nervous system
somatic nervous system
VOLUNTARY
- includes both sensory and motor neurons
somatic sensory neurons
afferent
- receptors for somatic senses
- receptors for special senses
somatic motor neurons
efferent
innervate skeletal muscles
Autonomic nervous system
INVOLUNTARY
- regulates cardiac muscles, smooth muscle, glandular tissue
- autonomic motor neurons regulate visceral activities by exciting or inhibiting activities in effector tissues
somatic sensory
carries signals from receptors in skin, muscles, bones, and joints
visceral sensory
carries signals mainly from organs in the thoracic and abdominal cavities
what is the difference between autonomic and somatic in the nervous system
somatic: direct highway to the muscle
autonomic: connects to ganglion then to muscle
which of the following statements best describes a difference between the CNS and PNS
1. the CNS is composed by the spinal cord, while the PNS is composed by cranial nerves
2. both the CNS and PNS exclusively consists of the brain and spinal cord
3. the PNS is responsible for processing sensory information, whereas the CNS is responsible for motor functions
4. the CNS and PNS are terms used interchangeably to describe the same set of neural structures
1.
which of the following sensory responses is NOT part of the somatic sensory division
1. proprioception
2. taste
3. pressure
4. vision
2.
general sensory receptors by structural class
- free nerve endings:
- encapsulated:
- proprioceptors
free nerve endings: sensory receptors
- nociceptors (pain)
- thermoreceptors (temp)
- mechanoreceptors (pressure)
- chemoreceptors
in most body tissue; most dense in CT
modified free nerve endings
merkel discs
mechanoreceptor (light pressure)
- deepest layer of epidermis
hair follicle receptors (free nerve endings)
mechanoreceptors (hair deflections)
- in and surrounding hair follicles
list the encapsulated sensory receptors
- tactile (Meissner’s corpuscles)
- lamellar (Pacinian corpuscles)
- Ruffini corpuscles
tactile (Meissner’s corpuscles)
- mechanoreceptor (light pressure, discriminative touch, vibration of low frequency)
- hairless skin (nipple, genitalia, finger tips, eyelids)
lamellar (Pacinian corpuscles)
- mechanoreceptor (deep pressure, stretch, vibration of high frequency)
- dermis and hypodermis; on fingers, soles of feet, genitalia, nipples
Ruffini corpuscles
- mechanoreceptors (deep pressure and stretch)
- deep in dermis, hypodermis, and joint capsules
sensory receptors proprioceptors
- muscle spindles
- tendon organs
muscle spindles
- mechanoreceptors (muscle stretch)
- skeletal muscles, particularly those of the extremities
tendon organs
mechanoreceptor (tendon stretch)
- tendons
which of the following is responsible for sensing proprioception
1. free nerve endings
2. merkel cells
3. muscle spindles
4. hair follicle receptor
3.