Ch 5

Question 1

Dark A bands of skeletal muscle fibers corresponds to the length of _____ filaments, and these bands _____ during contraction

Answer 1

Myosin

Stay the same width

Question 2

An Olympic sprinter would likely have a higher proportion of _____ fibers than an Olympic marathon runner

Answer 2

Fast glycolytic

Question 3

Red skeletal muscle fibers have a relatively _____ twitch speed and primarily use _____ respiration

Answer 3

Slow

Aerobic

Question 4

Tetanus in a muscle cell is caused by ___ in the sarcoplasm

Answer 4

Accumulation of calcium ions

Question 5

The sliding filament model of contraction in striated muscle involves ____ during contraction

Answer 5

Myosin pulling actin toward the center of the sarcomere

Question 6

During skeletal muscle excitation, ____\ is released by motor neurons at the neuromuscular junction

Answer 6

ACh

Question 7

The asymmetric activation of ____ causes relative movement of _____ pairs in the axoneme during ciliary and flagellar movement

Answer 7

Dynein

Microtubule

Question 8

A low concentration of calcium ions in the sarcoplasm promotes

Answer 8

The blockage of binding sites on actin

Question 9

During skeletal muscle relaxation, calcium ions move into the

Answer 9

Sarcoplasmic reticulum

Question 10

The extension of the cell membrane during amoeboid movement is cause by ____

Answer 10

Actin polymerization

Question 11

Microfilaments are polymers composed of the protein ____ and they (microfilaments) are

Answer 11

Actin

Part of the cytoskeleton

Question 12

During the dispersion of pigment granules in a melanocyte, the ___ guides the path of movement and _____ provides the mechanical force for movement

Answer 12

Microtubule

Kinesin

Question 13

The structure of an axoneme in a ____ consisted of microtubules in a ____ arrangement

Answer 13

Flagellum

Nine plus two

Question 14

Isoforms of ____ provide the functional properties of different types of striated muscle fibers in mammals

Answer 14

Myosin II

Question 15

In smooth muscle, _____ binds calcium ions during contraction and ___ blocks binding sites on actin during relaxation

Answer 15

Calmodulin

Caldesmon

Question 16

In contrast to skeletal muscle, cardiac muscle is ______ and has a _____ refractory period

Answer 16

Myogenic

Long

Question 17

_____ muscle lacks striations, sarcomeres, and t tubules

Answer 17

Smooth

Question 18

The walls of the _____ do not have smooth muscle

Answer 18

Heart

Question 19

The electric organs of fish are composed of modified muscle referred to as _____

Answer 19

Trans-differentiated

Question 20

In contrast to resistance (strength) training, endurance training tends to increase _____ in skeletal muscle fibers and convert fibers from ______

Answer 20

Myoglobin content

Fast-glycolytic to fast-oxidative

Question 21

During skeletal muscle contraction, calcium ions move from the _____ into the _____

Answer 21

Sarcoplasmic reticulum

Sarcoplasm

Question 22

Microtubules are polymers composed of the protein ______ and they (microtubules) are _____

Answer 22

Tubulin

Part of the cytoskeleton

Question 23

Movement due to microfilaments often uses the motor protein _____

Answer 23

Myosin

Question 24

An increase in the number of activated motor units for a muscle is referred to as

Answer 24

Recruitment

Question 25

Summation does not occur in _____ muscle because of a relatively ______ refractory period

Answer 25

Cardiac

Long