Question 1

Which of the following statements best distinguishes cardiac muscle from skeletal and smooth muscle?

Accepted Answer

Cardiac muscle is striated and involuntary, found only in the heart.

Question 2

A patient is unable to consciously contract a certain muscle, and microscopic examination reveals no striations. Which type of muscle tissue is most likely affected?

Accepted Answer

Smooth muscle

Question 3

Which connective tissue sheath directly surrounds each individual muscle fiber?

Accepted Answer

Endomysium

Question 4

During a muscle contraction, which of the following events occurs according to the sliding filament model?

Accepted Answer

Actin and myosin filaments slide past each other, shortening the sarcomere.

Question 5

Which of the following best describes the role of calcium ions ($$\mathrm{Ca$$^{2+}$$}) in $$skeletal muscle contraction?

Accepted Answer

They bind to troponin, causing exposure of myosin-binding sites on actin.

Question 6

A muscle is attached to bone via a tough, ropelike structure. What is the primary advantage of this type of attachment?

Accepted Answer

It provides durability and allows multiple muscles to pass over a joint, conserving space.

Question 7

Which of the following is NOT a characteristic of muscle tissue?

Accepted Answer

Calcification

Question 8

A researcher is studying the basic contractile unit of skeletal muscle. Which structure should they focus on?

Accepted Answer

Sarcomere

Question 9

Which of the following best describes the sequence of events at the neuromuscular junction leading to muscle contraction?

Accepted Answer

ACh is released from the motor neuron, causing an end plate potential that triggers an action potential in the sarcolemma.

Question 10

Which protein directly binds oxygen within muscle cells, allowing for increased oxygen storage?

Accepted Answer

Myoglobin

Question 11

A muscle fiber is unable to contract even though it receives a normal action potential. Which of the following is the most likely explanation?

Accepted Answer

Calcium ions are not being released from the sarcoplasmic reticulum.

Question 12

Which of the following best explains why indirect muscle attachments (via tendons) are more common than direct attachments?

Accepted Answer

Tendons are tough, durable, and allow more muscles to attach to a joint, conserving space.

Question 13

Which of the following is the correct order of connective tissue sheaths from outermost to innermost in a skeletal muscle?

Accepted Answer

Epimysium, perimysium, endomysium

Question 14

Which of the following best describes the function of the sarcolemma?

Accepted Answer

It is the plasma membrane of the muscle fiber, conducting action potentials.

Question 15

A patient with a genetic defect in the protein myosin would most likely experience which of the following symptoms?

Accepted Answer

Impaired muscle contraction due to inability to form cross bridges with actin

Question 16

Which of the following is a function of muscle tissue that is especially important for maintaining homeostasis during cold exposure?

Accepted Answer

Generating heat as they contract

Question 17

During the cross bridge cycle, what event immediately follows the binding of myosin heads to actin?

Accepted Answer

The power stroke, where myosin heads pivot and pull actin filaments toward the M line

Question 18

Which of the following best describes the role of the perimysium in skeletal muscle?

Accepted Answer

It surrounds bundles of muscle fibers (fascicles).

Question 19

A muscle biopsy reveals elongated, multinucleated cells with peripheral nuclei and visible striations. Which type of muscle is this?

Accepted Answer

Skeletal muscle

Question 20

Which of the following best explains why skeletal muscle fibers are multinucleated?

Accepted Answer

They fuse from several cells during development, retaining all original nuclei.

Chapter 9: Muscles & Muscle Tissue – Study Guide

Guida di studio - Domande di pratica

Study guide - Flashcard