Lecture 15: Muscular And Nervous System

Question 0

Twitch contraction

Answer 0

One motor unit contracting and relaxing

Question 1

Motor units

Answer 1

Neuron and all the muscle fibers it contacts. Staggered to vary recruitment and in case of damage. 1-2000 units based on task.

Question 2

Wave summation

Answer 2

Fiber doesn’t completely relax before the next stimulus and subsequent contractions are stronger

Question 3

Fused tetanus

Answer 3

Stimuli are coming so fast there’s sustained contraction

Question 4

Flaccid muscle tone

Answer 4

Lack of tone, no contraction (possibly due to neuron damage)

Question 5

Isotonic contraction

Answer 5

Movement changing angle in joint

Question 6

Eccentric

Answer 6

Increasing joint angle

Question 7

Concentric

Answer 7

Decreasing joint angle

Question 8

Isometric

Answer 8

Tension in muscle with no change in length

Question 9

Muscle regeneration

Answer 9

Satellite cells fuse with muscle fiber (small tears). Large scale damage to fibers is converted to scar tissue (fibrosis).

Question 10

Disuse atrophy

Answer 10

Muscle shrinks

Question 11

Denervation atrophy

Answer 11

No nervous stimulation (spinal cord injury)

Question 12

Brain

Answer 12

100 billion neurons

Question 13

Spinal cord

Answer 13

100 million neurons

Question 14

Cranial nerves

Answer 14

12 pairs

Question 15

Spinal nerves

Answer 15

31 pairs

Question 16

Ganglia

Answer 16

Groups of neuronal cell bodies outside brain and spinal cord

Question 17

Enteric plexuses

Answer 17

Neurons regulating digestion

Question 18

Sensory functions

Answer 18

Receptors transmit info to brain and spinal cord via afferent neurons

Question 19

Integrative function

Answer 19

Processing and analysis via interneurons

Question 20

Motor function

Answer 20

Info sent to effectors via efferent neurons

Question 21

CNS

Answer 21

(Brain and spinal cord)

Question 22

PNS

Answer 22

Cranial and spinal nerves

Question 23

SNS (somatic)

Answer 23

Voluntary actions, senses

Question 24

ANS (autonomic)

Answer 24

Involuntary