Apologia Advanced Biology Module 5 Lecture 2

Front 1

Motor unit

Back 1

One motor neuron and all the muscle fibers it innervates

Front 2

Two muscle fibers lie side by side. They contract and relax differently, however. Are these two fibers a part of the same motor unit?

Back 2

They are not a part of the same motor unit

Front 3

All-or-none law of skeletal muscle contraction

Back 3

An individual muscle fiber contracts with equal force in response to each action potential.

Front 4

Subthreshold stimulus

Back 4

A stimulus too small to create an action potential in a neuron.

Front 5

Threshold stimulus

Back 5

A stimulus strong enough to create one action potential in a neuron

Front 6

Submaximal stimuli

Back 6

Stimuli of increasing strength that create more action potentials along more neurons

Front 7

Maximal stimulus

Back 7

A stimulus which is strong enough to create action potentials in all the motor neurons innervating a whole muscle

Front 8

supramaximal stimulus

Back 8

more stimulus is given but it produces no further effect.

Front 9

multiple motor unit summation

Back 9

a lot of motor units are recruited, the muscle contracts with greater force. it allows the individual muscle fibers to contract in an all-or-none way while the overall muscle contracts with differing amounts of force, depending on the nerve stimulus involved.

Front 10

A muscle contracts, but only a small percentage of its motor units have been recruited. What kind of stimulus (threshold, submaximal, maximal, or supramaximal) is being applied?

Back 10

submaximal stimulus

Front 11

Muscle tone

Back 11

The state of partial contraction in a muscle, even when the muscle is not being used

Front 12

atrophy

Back 12

When muscles shrink due to the lack of use

Front 13

aerobic respiration

Back 13

is a three-step process in which glucose reacts with oxygen, and the energy from that process is used to turn ADP and P into ATP.

Front 14

anaerobic respiration

Back 14

is actually the first step in aerobic respiration called glycolysis, simply involves a glucose molecule being broken down into two pyruvic acid molecules and four ATPs.

Front 15

oxygen debt

Back 15

pay it back” by breathing when we're at rest

Front 16

Motor unit

Back 16

One motor neuron and all the muscle fibers it innervates

Front 17

Two muscle fibers lie side by side. They contract and relax differently, however. Are these two fibers a part of the same motor unit?

Back 17

They are not a part of the same motor unit

Front 18

All-or-none law of skeletal muscle contraction

Back 18

An individual muscle fiber contracts with equal force in response to each action potential.

Front 19

Subthreshold stimulus

Back 19

A stimulus too small to create an action potential in a neuron.

Front 20

Threshold stimulus

Back 20

A stimulus strong enough to create one action potential in a neuron

Front 21

The cells in a person's leg muscles all have a large amount of lactic acid in them. What can you say about the amount of creatine phosphate in those cells?

Back 21

there must be little or no creatine phosphate in the cells.

Front 22

Suppose the person in the previous question is currently resting. Is he or she mostly likely breathing heavily or breathing normally?

Back 22

The person is breathing heavily