Deck 12: Microscopic Anatomy and Organization of Skeletal Muscle

Question 1

Sarcomeres consist of _.

A)myofibrils arranged one after the other
B)bands of tissue wrapped around the sarcolemma
C)orderly arrangements of actin and myosin

Answer 1

C

Question 2

Terminal cisterns .

A)carry the action potential deep into the muscle cell
B)are an important link between the nervous system and the muscle cell
C)store acetylcholine
D)are made of smooth endoplasmic reticulum

Answer 2

D

Question 3

Each of the elements that make up a skeletal muscle is surrounded by connective tissue. Which words below correctly pair the connective tissue layer with the corresponding muscle structure?

A)muscle fiber: deep fascia
B)functional group of muscles: endomysium
C)fascicle: perimysium
D)entire muscle: epimysium

Answer 3

C

Question 4

The actual contractile units of muscles extend from Z disc to Z disc. They are .

A)thick filaments
B)sarcomeres
C)sarcoplasmic reticulum
D)myofibrils

Question 5

The dark band of skeletal muscle results from the alignment of .

A)thick filaments
B)elastic filaments
C)T tubules
D)thin filaments

Question 6

The space between the axon terminal and the sarcolemma of a muscle fiber is called the .

A)synaptic cleft
B)muscle gap
C)aponeurosis cleft
D)nerve gap

Question 7

A neuron and all the muscle fibers it stimulates is called a .

A)motor unit
B)myoneural junction
C)synaptic cleft
D)fascicle

Question 8

An aponeurosis is .

A)a covering of the myoneural region
B)a disease of the neuromuscular junction
C)similar to a tendon in function
D)a structural part of the interior of muscle cells

Question 9

From gross to microscopic levels, the parts of a muscle are .

A)fascicle muscle, fiber
B)fiber, fascicle, muscle
C)muscle, fiber, fascicle
D)muscle, fascicle, fiber

Question 10

Acetylcholine (Ach)is the neurotransmitter of axon terminals at the neuromuscular junction. It .

A)diffuses across the synaptic cleft, binds to receptors on the muscle membrane, and ultimately causes the muscle to depolarize and contract
B)diffuses across the synaptic cleft
C)ultimately causes the muscle to depolarize and contract
D)binds to receptors on the muscle membrane

Question 11

This indentation of the sarcolemma carries electrical signals deep into the muscle cells.

A)triad
B)T tubule
C)sarcoplasmic reticulum
D)terminal cisterns

Question 12

This strong, cord- like structure attaches muscles to bones.

A)ligament
B)deep fascia
C)tendon

Question 13

The neuromuscular junction consists of .

A)the axon terminal coming into close proximity to a muscle fiber
B)the end branch of a single nerve fiber touching a muscle
C)a nerve touching a muscle
D)a nerve coming into close proximity to a muscle fiber

Question 14

What is the correct order of structures as you move from outside a muscle cell, to deep inside it?

A)fiber, myofibril, myofilament
B)myofibril, myofilament, fiber
C)myofilament, myofibril, fiber
D)myofilament, fiber, myofibril

Question 15

This contractile protein is shaped like a golf club.

A)tropomyosin
B)troponin
C)myosin
D)actin

Question 16

This contractile protein forms the thin filaments.

A)actin
B)titin
C)dystrophin
D)myosin

Question 17

The thick and thin filaments are made up of _.

A)the dark and light bands
B)myosin and actin
C)the H zone and the Z disc
D)T tubules and terminal cisterns.

Question 18

The function of the neuromuscular junction is to .

A)stimulate or inhibit the activity of skeletal muscles
B)connect the nervous system directly to muscle
C)convey a signal from the nervous system to skeletal muscle
D)link nerve endings to muscle, to protect the nerve structurally

Question 19

A muscle fiber is _ .

A)a rod- like structure consisting of sarcomeres placed end to end.
B)an arrangement of actin and myosin filaments deep within a muscle cell.
C)a muscle cell.

Question 20

At the neuromuscular junction, the electrical signal of the nerve .

A)is sent directly to muscle
B)causes the axon terminal to release acetylcholine (Ach)
C)stimulates formation of the neurotransmitter acetylcholine (ACh)
D)causes the axon terminal to release Na+ and K+

Question 21

Tendons differ from ligaments in that .

A)they are formed from different tissue types
B)tendons are broad and flat and ligaments are like cords
C)tendons attach to bone and ligaments do not
D)tendons bind muscle to bone and ligaments bind bone to bone