Question 1

Which of the following best explains the underlying cause of Duchenne Muscular Dystrophy?

Accepted Answer

Mutation or absence of the gene encoding dystrophin, which links the cytoskeleton to the muscle cell membrane

Question 2

A patient with myasthenia gravis is experiencing muscle weakness. Which mechanism is primarily responsible for this symptom?

Accepted Answer

Antibodies blocking acetylcholine receptors, preventing normal neurotransmitter binding

Question 3

Amyotrophic Lateral Sclerosis (ALS) leads to muscle paralysis primarily due to:

Accepted Answer

Progressive death of motor neurons, resulting in loss of stimulation to muscles

Question 4

Which muscle disorder is most likely to present with widespread pain, fatigue, and cognitive symptoms, but does NOT primarily involve muscle anatomy?

Accepted Answer

Fibromyalgia

Question 5

Malignant hyperthermia is a life-threatening condition triggered by certain anesthetics. What is the primary physiological problem in this disorder?

Accepted Answer

Massive release of calcium from the sarcoplasmic reticulum into the cytoplasm

Question 6

Which equation best represents the role of calcium in muscle contraction?

Accepted Answer

$$Ca^{2+} + $$Troponin \rightarrow $$Troponin-Ca^{2+}$$

Question 7

A child with nemaline myopathy is prescribed resistance training. What cellular adaptation is most likely to occur in their muscle cells?

Accepted Answer

Increase in the number of mitochondria and myofibrils

Question 8

If a patient is unable to dorsiflex their foot after a hip dislocation, which nerve is most likely affected?

Accepted Answer

Sciatic nerve

Question 9

Which muscle is primarily responsible for flexing the leg at the knee?

Accepted Answer

Biceps femoris

Question 10

During a physical therapy assessment, resistance is applied to the top of a patient's foot as they attempt to bring their forefoot up toward their shin. Which muscle is being tested?

Accepted Answer

Tibialis anterior

Question 11

Which of the following best describes the function of the sarcoplasmic reticulum in skeletal muscle?

Accepted Answer

Stores and releases calcium ions to initiate muscle contraction

Question 12

A muscle that opposes the action of another muscle is called a(n):

Accepted Answer

Antagonist

Question 13

Which of the following is a plausible consequence of abnormal troponin in nemaline myopathy?

Accepted Answer

Impaired calcium binding, leading to reduced muscle contraction strength

Question 14

Which muscle originates on the posterior surface of the femur and inserts on the posterior surface of the tibia?

Accepted Answer

Flexes the leg at the knee

Question 15

Which of the following equations best represents the process of cross-bridge cycling in muscle contraction?

Accepted Answer

$$ATP + Myosin \rightarrow Myosin-ATP \rightarrow Myosin + ADP + P_i$$

Question 16

Which muscle is being assessed when resistance is applied to the patient's heel as they attempt to bring their heel up toward their buttocks in the prone position?

Accepted Answer

Hamstrings (e.g., biceps femoris)

Question 17

Which of the following is a common misconception about fibromyalgia?

Accepted Answer

It is caused by muscle degeneration

Question 18

Which muscle is tested when resistance is applied to the lateral side of the foot as the patient attempts to evert the foot?

Accepted Answer

Peroneus (fibularis) longus

Question 19

Which of the following is a real-life consequence of a massive release of calcium into the cytoplasm during malignant hyperthermia?

Accepted Answer

Sustained muscle contraction and dangerously increased body temperature

Question 20

Which muscle is primarily responsible for flexing the big toe?

Accepted Answer

Flexor hallucis longus

Muscle-Associated Disorders and Clinical Applications (Muscles pt iii, BIOL1300 Lecture 12)

Study Guide - Practice Questions

Study Guide - Flashcards