Test #2

Question 1

In skeletal muscle crossbride cycling, ATP

Answer 1

Allows myosin to release actin and reset to the energized position

Question 2

Which type of muscle fiber is least resistant to fatigue?

Answer 2

Fast gly

Question 3

When an acetylcholinesterase (AChE) antagonist is in the synapse

Answer 3

There will be more acetylcholine in the synapse

Question 4

Rigor mortis is because of

Answer 4

ATP, which is necessary for the removal of Ca from the sarcomere, is not being formed

Question 5

Which of the following statements regarding the shortening of a skeletal-muscle fiber is not true? When a skeletal-muscle fiber shortens,

Answer 5

the actin and myosin myofilaments shorten

Question 6

Which neurotransmitter system is implicated in Parkinson’s disease?

Answer 6

Dopamine

Question 7

The tension in a skeletal muscle can be increased by

Answer 7

Temporal summation of a muscle fiber

Motor unit summation

Question 8

An inhibitory postsynaptic potential (IPSP)

Answer 8

Is produced by an increased membrane permeability to K

Question 9

What will happen to the concentration of a neurotransmitter in a synaptic cleft when the frequency of action potentials increases in the presynaptic neuron?

Answer 9

It increases

Question 10

The EPSPs from two different synapses occur at the same time and cause a larger depolarization than either one alone could cause. This is an example of

Answer 10

Spatial summation in neurons

Question 11

Which of the following is a parasympathetic nervous system function?

Answer 11

Increase smooth muscle contraction in the digestive tract

Question 12

The binding of a neurotransmitter to its receptor at an inhibitory synapse can lead to the ____ of ____ channels

Answer 12

Opening; potassium

Question 13

Predict the response of the smooth muscle of the uterus to sympathetic nervous system stimulation.

Answer 13

Inhibition and relaxation

Question 14

Exocytosis of a neurotransmitter into the synaptic cleft is triggered by an influx of _____ (to the presynaptic cell) in response to the arrival of an action potential in the axon terminal.

Answer 14

Ca+2

Question 15

When a skeletal muscle has been working for an extended period of time (more than 15 minutes, but less than 40), the primary source of ATP is

Answer 15

Metabolism of blood glucose

Question 16

The transverse (T) tubules in a skeletal muscle fiber

Answer 16

Provide a means of transmitting an action potential in the muscle sarcolemma to the central portions of the muscle fiber

Question 17

The neurotransmitter used in communication between a sympathetic motor neuron and a cardiac muscle cell is:

Answer 17

Norepinephrine

Question 18

Which of the following is a biogenic amine that is NOT classified as a catecholamine?

Answer 18

Serotonin

Question 19

Place the following steps of crossbridge formation in the correct order

i. AP reaches T-tubules
ii. Tropomyosin moves to reveal active sites
iii. Ca2+ is released from the SR
iv. Crossbridge forms
v. Ca+2 binds to troponin

Answer 19

3,1,5,2,4

Question 20

Which of the following statements about acetylcholine is correct?

Answer 20

Acetylcholine binds to cholinergic receptors

Acetylcholine binds to nicotinic and muscarinic receptors

Question 21

An EPSP in a membrane

Answer 21

Is often a direct result of the opening of chemical-gated Na+ channels in the membrane

Question 22

“Motor-Unit” refers to

Answer 22

a single motor neuron plus all of the skeletal muscle fibers it innervates

Question 23

a marathon runner’s legs would likely contain extremely well-trained ____ fibers?

Answer 23

Slow ox

Question 24

A myofibril is

Answer 24

Composed of actin and myosin

Composed of proteins

Question 25

The way in which the nervous system can detect the intensity of a stimulus is

Answer 25

The frequency of action potentials

Question 26

During a skeletal muscle fiber twitch, Ca is pumped back into the sarcoplasmic reticulum primarily during the _____ phase.

Answer 26

Relaxation

Question 27

Which of the following neurotransmitters is lipid-soluble and is contained in chocolate?

Answer 27

Anadamide

Question 28

The response of a single skeletal much cell to a single action potential is termed:

Answer 28

A twitch

Question 29

Calcium is released from the sarcoplasmic reticulum and then travels to the sarcomere via _____ and it is taken back up into the SR via _____

Answer 29

Diffusion; primary active transport

Question 30

Which of the following neurotransmitters bind to adrenergic receptors?

Answer 30

a. Adrenaline b. Epinephrine c. Norepinephrine

Question 31

No Question

Answer 31

Freebee

Question 32

____ is an amino acid neurotransmitter at excitatory synapses whereas ____ is an amino acid neurotransmitter at inhibitory synapses.

Answer 32

Aspartate; glycine

Question 33

The neurotransmitter released from postganglionic neurons in the parasympathetic nervous system is

Answer 33

Acetylcholine

Question 34

Endorphins and enkephalins bind to which of the following receptors

Answer 34

Opiod

Question 35

The release of a phosphate from the myosin molecule directly results in which of the following?

Answer 35

Release of the crossbridge

Question 36

Put the following sources of energy from skeletal muscle contraction in the order in which they would be utilized; i. ATP bound to myosin thick filaments ii. Blood glucose iii. Creatine phosphate iv. Fatty acid metabolism v. Stored glycogen

Answer 36

2,3,1,4,5

Question 37

The binding of calcium to troponin will directly cause which of the following

Answer 37

The movement of tropomyosin, exposing the actin active sites

Question 38

Aerobic, or low-intensity, muscle training eventually results in

Answer 38

More capillaries | More myoglobin

Question 39

What is the effect of parasympathetic postganglionic acetylcholine?

Answer 39

Not enough information to determine

Question 40

The preganglionic synapses in the sympathetic nervous system are

Answer 40

Excitatory and cholinergic

Question 41

In a resting state, _____ covers the actin active site

Answer 41

Tropomyosin

Question 42

Students who suffer from test anxiety often have some of the following symptoms: increased heart rate, dilated pupils, and a dry mouth. What branch of the autonomic nervous system would cause these symptoms?

Answer 42

Sympathetic

Question 43

The time between the occurrence of an AP in skeletal muscle and the onset of tension is called what?

Answer 43

Latent period

Question 44

What are the three types of muscle fibers that are found in skeletal muscles?

Answer 44

Slow ox, fast ox, fast gly

Question 45

What is a change in the postsynaptic potential that brings membrane potential closer to threshold called?

Answer 45

Excitatory postsynaptic potential

Question 46

Convergence in neuron physiology refers to which of the following?

Answer 46

The communication of several neurons to one postsynaptic cell

Question 47

Multi-unit smooth muscle has gap junctions and all cells act as a single functional unit

Answer 47

False

Question 48

Muscles used for delicate, finely controlled movements have smaller, more numerous motor units than more coarsely controlled muscles

Answer 48

True

Question 49

During skeletal muscles contraction, the I band and H zone shorten but the A band stays the same

Answer 49

True

Question 50

The neurotransmitter used primarily for reward and reinforcement in the CNS is GABA.

Answer 50

False