Chapter 13

Question 1

What are the 4 ways to classify neural pathways?

Answer 1

1. By the efferent division that controls the response (somatic v. autonomic)
2. By the CNS location where the reflex is integrated (spinal v. cranial reflexes)
3. Innate or learned (conditioned) reflex
4. By the number of neurons in the reflex pathway (monosynaptic or polysynaptic

Question 2

What is monosynaptic?

Answer 2

2 neurons with 1 Ganglia (i think this is what it is??)
(one sensory and one motor neuron)

Question 3

What is polysynaptic?

Answer 3

3 neurons with 2 ganglia (i think this is what it is??)
- ALL cranial reflexes are polysynaptic (the three levels of neurons in the brain)

Question 4

Figure 13.1c

Question 5

What are autonomic reflexes? What is another name for them?

Answer 5

• AKA visceral reflexes
• Some are spinal reflexes with brain modulation
• Some are integrated in the brain
• Polysynaptic

Question 6

Figure 13.1a

Question 7

What are muscle spindles?

Answer 7

• stretch receptors
• encode signals about muscle length and changes in muscle length

Question 8

What are sensory receptors in the skeletal muscle reflexes called? Where are they located?

Answer 8

• called proprioceptors
• located in skeletal muscle, joint capsules, and ligaments

Question 9

Where do proprioceptors send signals to?

Answer 9

Input signals from proprioceptors go to t he CNS through sensory neurons

Question 10

Look at slide 13 for the skeletal muscle reflex

Question 11

What are the effectors in the skeletal muscle reflex?

Answer 11

contractile skeletal muscle fibers
- AKA extrafusal muscle fibers

Question 12

What is the stretch reflex?

Answer 12

a contraction response to the muscle stretch

Question 13

What is the muscle stretch reflex?

Answer 13

1. load added to muscle
2. muscle and muscle spindles stretch as arm extends (muscle spindle afferent fire more frequently)
3. Reflex contraction initiated by muscle stretch restores arm position and prevents damage from over-stretching

Question 14

figure 13.5

Question 15

What is a myotatic unit?What type and describe its stretch reflex?

Answer 15

• collection of pathways controlling a single joint
• Monosynaptic stretch reflex involves only 2 neurons (seonsry neuron from spindle somatic motor neuron to muscle — patellar tendon reflex)

Question 16

What is reciprical inhibition?

Answer 16

antagonist ic muscles must relax as the prime mover muscles contract (polysynaptic)

Question 17

What does the flexion reflex accomplish?

Answer 17

• pulls limbs away from painful stimuli (nociceptors)
• polysynaptic
• associated with crossed extensor reflexes

Question 18

Figure 13.6

Question 19

What is the role of the spinal cord?

Answer 19

spinal reflexes, locomotor pattern generators

Question 20

What is the role of the brain stem?

Answer 20

posture, hand and eye mvoements

Question 21

What is the role of the motor areas of the cerebral cortex?

Answer 21

planning and coordinating complex movement

Question 22

What is the role of the cerebellum?

Answer 22

Monitors output signals from motor areas and adjusts movements

Question 23

What is the role thalamus?

Answer 23

Contains relay nuclei that modulate and pass messages to cerebral cortex

Question 24

What is the role of the basal anglia?

Answer 24

motor planning

Question 25

figure 13.7

Question 26

What are the 3 levels of nervous system control?

Answer 26

1. spinal cord (integrates spinal reflexes, contains central pattern generators)
2. Brain stem and cerebellum (postural reflexes and eye/hand movements)
3. Cerebral cortex and basal ganglia (voluntary movements)

Question 27

What is the corticospinal tract?

Answer 27

neurons from motor cortex to spinal cord

Question 28

What does smooth and cardiac muscle control movement?

Answer 28

hormones or autonomic division of nervous system