exam 4 a&p

1. Which characteristics describe both skeletal and cardiac muscle? a. striations b. autorhymicity c. cell shape d. autonomic control

*a. striations

In skeletal muscles, the combined amounts of creatine phosphate and ATP provide enough energy for the muscle to contract maximally for approximately a. 15 seconds. b. 15 minutes. c. 1.5 minutes. d. 5 seconds.

a. 15 seconds.

In the diagram, which structure(s) moves towards the center of the sarcomere (closer together) when the fiber contracts? a. A b. C c. J d. Both A and C

a. A

On the diagram, what structure is composed of the three connective tissue layers that extend past the muscle? a. A b. B c. E d. G e. H

a. A

Which ATP production would be sufficient to run in place for one minute? a. creatine phosphate b. anaerobic cellular respiration c. aerobic cellular respiration

b. anaerobic cellular respiration

Smooth muscle tone is maintained by the prolonged presence of [_____] in the muscle cell's cytosol? a. ATP b. calcium ions c. sodium ions d. acetylcholine e. oxygen

b. calcium ions

Which term describes a somatic motor neuron and all the skeletal muscle fibers it stimulates? a. synapse b. motor unit c. neuromuscular junction d. motor end plate

b. motor unit

Which functions as a motor protein in all three types of muscle tissue? a. actin b. myosin c. troponin d. titin e. tropomyosin

b. myosin

Place the muscle tissue type in order from least to most ability to regenerate. a. smooth, skeletal, cardiac b. skeletal, cardiac, smooth c. cardiac, smooth, skeletal d. skeletal, smooth, cardiac e. cardiac, skeletal, smooth

b. skeletal, cardiac, smooth

In the diagram, which structure helps return a stretched sarcomere to its resting length? a. B b. C c. E d. Both B and C e. All of these choices are correct.

c. E

In the diagram, what area contains both thick and thin filaments? a. G b. I c. H d. Both B and C

c. H

During muscle contractions, thin filaments are pulled towards the a. Z disc. b. H zone. c. M line. d. A band. e. I band.

c. M line.

Contraction of myofibrils within a muscle fiber begins when a. sodium enters the muscle fiber b. acetylcholine binds to ligand gates c. calcium is released from the sarcoplasmic reticulum d. an action potential travels t-tubules e. calcium is moved into the sarcoplasmic reticulum

c. calcium is released from the sarcoplasmic reticulum

Which property of muscle gives it the ability to stretch without damage? a. electrical excitability b. contractility c. extensibility d. elasticity

c. extensibility

World class shot-putters will have a higher percentage of ______in their arm muscles. a. slow oxidative fibers b. fast oxidative fibers c. fast glycolytic fibers

c. fast glycolytic fibers

Skeletal muscle contraction is triggered to begin when calcium is released from a. myofibrils b. mitochondria c. terminal cisterns of sarcoplasmic reticulum d. T-tubules

c. terminal cisterns of sarcoplasmic reticulum

What energizes the myosin head? a. acetylcholine b. calcium ions c. Phosphate release d. ATP hydrolysis reaction e. ADP synthesis

d. ATP hydrolysis reaction

Which region of a sarcomere contain thin filaments? a. I band b. A band c. H zone d. Both I band and A band.

d. Both I band and A band.

In the diagram, where would you find stored Ca 2+? a. B b. D c. G d. F e. K

d. F

Which correctly lists the sequence of structures that action potentials must move through to excite skeletal muscle contraction? a. sarcolemma, axon of neuron, T tubules b. T tubules, sarcolemma, myofilament c. muscle fiber, axon of neuron, myofibrils d. axon of neuron, sarcolemma, T tubules e. myofibrils, myofilaments, mitochondria

d. axon of neuron, sarcolemma, T tubules

The outermost layer of connective tissue surrounding a skeletal muscle is the a. tendon b. ligament c. endomysium d. epimysium e. perimysium

d. epimysium

Which of the regions of a sarcomere contain titin? a. the A band only b. the H zone only c. the zone of overlap only d. from M line to Z disc e. the I band only

d. from M line to Z disc

After the fusion of myoblasts, the muscle fiber loses its ability to a. grow b. lengthen c. contract d. go through mitosis

d. go through mitosis

Which microscopic structure is found only in the cardiac muscle tissue? a. myosin b. tropomyosin c. sarcomeres d. intercalated discs e. striations

d. intercalated discs

In the diagram, what area is composed of only thick filaments? a. C b. E c. A d. B e. D

e. D

The opening of ligand gates on the sarcolemma is directly caused by a. acetylcholine attachment. b. calcium influx into the motor neuron . c. sodium influx into the muscle fiber. d. acetylcholinesterase activity. e. all choices are correct.

e. all choices are correct.

Which protein is used to reinforce the sarcolemma and help transmit the tension generated by the sarcomeres to the tendons? a. troponin b. tropomyosin c. myosin d. actin e. dystrophin

e. dystrophin

In the diagram, calcium ions will rush into this area. a. B b. C c. D

a. B

In the diagram, where are troponin, tropomyosin and nebulin located? a. B b. C c. S d. E e. D

a. B

In the diagram, what structure contains motor proteins that convert the energy in ATP into mechanical movements? a. C b. A c. E d. D

a. C

In the diagram, how do action potentials penetrate the outside of the muscle fiber? a. D b. E c. L d. K e. A

a. D

At the neuromuscular junction, _______ must enter the synaptic end bulb to stimulate the release of ____________, which binds to ligand gates so ________ can enter the muscle fiber. a. calcium ions; ACh, sodium ions b. sodium ions, calcium ions, ACh c. ACh, calcium ions, sodium ions d. sodium ions, ACh, calcium ions e. calcium ions, sodium ions, ACh

a. calcium ions; ACh, sodium ions

Which type of muscle tissue contracts when excited by their own autorhythmic muscle fibers? a. cardiac muscle b. slow twitch oxidative skeletal muscle c. multi-unit smooth muscle d. fast twitch glycolytic skeletal muscle

a. cardiac muscle

Motor unit recruitment occurs when there is a(n) [increase] in the number of active motor units within a skeletal muscle. a. increase b. decrease c. no change

a. increase

. Which function do all three muscles perform? a. moving and storing material throughout the body b. generating heat through contractions c. stabilizing the movement of joints d. promoting movement of body structures

a. moving and storing material throughout the body

Why would cardiac muscles have longer refractory periods than skeletal muscles. Choose the best answer? a. to preserve the normal rhythm of the heart and prevent fatigue b. the muscle types contain different contractile proteins c. skeletal muscle is autorhythmic d. skeletal muscles have prolonged calcium influx e. cardiac muscle is not dependent on aerobic respiration to produce ATP

a. to preserve the normal rhythm of the heart and prevent fatigue

Which of the following structures are made of dense regular connective tissue? a. F b. A c. I d. Both F and I

b. A

On the diagram, which layer is composed of dense irregular and surrounds a muscle? a. A b. B c. C d. D e. E

b. B

n the diagram, acetylcholine is released from ____ and diffuses to _____. a. A; B b. B; E c. C; A d. D; C e. E; B

b. B; E

A brief contraction of all muscle fibers in a motor unit in response to a single action potential moving down the somatic motor neuron is known as a. unfused tetanus. b. fused tetanus. c. wave summation. d. refractory period. e. twitch contraction.

e. twitch contraction.