Question 1

Which component of bone matrix is primarily responsible for the bone's tensile strength, and what is its main constituent?

Accepted Answer

Osteoid; composed mainly of collagen fibers

Question 2

During endochondral ossification, which sequence correctly describes the order of events leading to the formation of long bones?

Accepted Answer

Formation of periosteum → development of primary ossification center → invasion of blood vessels → formation of secondary ossification centers

Question 3

A patient with a deficiency in parathyroid hormone (PTH) would most likely exhibit which of the following symptoms?

Accepted Answer

Decreased blood calcium levels due to reduced bone resorption

Question 4

Which of the following best describes the architectural difference between spongy bone and compact bone?

Accepted Answer

Spongy bone contains trabeculae arranged in a lattice, while compact bone is organized into osteons with central canals

Question 5

Which hormone is primarily responsible for stimulating the epiphyseal plate during childhood growth, and what is its effect?

Accepted Answer

Growth hormone; stimulates chondrocyte division and matrix production

Question 6

A fracture healing process involves several stages. Which stage is characterized by the formation of a soft callus composed mainly of cartilage and fibrous tissue?

Accepted Answer

Fibrocartilage callus formation

Question 7

Which of the following cell types is responsible for bone resorption, and what enzyme does it use to break down the bone matrix?

Accepted Answer

Osteoclasts; acid phosphatase

Question 8

Which type of cartilage is found at the articular surfaces of synovial joints, and what is its primary function?

Accepted Answer

Hyaline cartilage; reduces friction and absorbs compressive forces

Question 9

A muscle fiber is stimulated and contracts. Which event occurs first in the excitation-contraction coupling process?

Accepted Answer

Depolarization of the sarcolemma at the motor end-plate

Question 10

Which of the following best explains the 'all or nothing' principle in skeletal muscle physiology at the level of an individual muscle fiber?

Accepted Answer

A muscle fiber contracts maximally if threshold is reached, or not at all if it is not

Question 11

During muscle contraction, ATP is required for which of the following steps?

Accepted Answer

Detachment of myosin heads from actin after the power stroke

Question 12

Which muscle fiber type is best suited for endurance activities, and what is its primary metabolic pathway?

Accepted Answer

Slow oxidative; aerobic metabolism

Question 13

A patient is experiencing muscle fatigue after intense exercise. Which metabolic pathway is most likely responsible for the rapid depletion of ATP in this scenario?

Accepted Answer

Anaerobic glycolysis producing lactic acid

Question 14

Which equation correctly represents the splitting of ATP during muscle contraction?

Accepted Answer

$$\mathrm{ATP} ightarrow \mathrm{ADP} + \mathrm{P_i} + 	ext{energy}$$

Question 15

Which structure in skeletal muscle is responsible for transmitting the action potential deep into the muscle fiber?

Accepted Answer

T-tubules

Question 16

In a muscle twitch, which phase corresponds to the time between stimulus and the onset of contraction, and what is happening during this phase?

Accepted Answer

Latent phase; action potential is propagating and calcium is being released

Question 17

Which of the following best describes the relationship between muscle tension and cross-sectional area?

Accepted Answer

Tension is directly proportional to cross-sectional area

Question 18

A muscle is contracting but its length does not change. What type of contraction is this, and what is the relationship between tension and load?

Accepted Answer

Isometric contraction; tension equals load

Question 19

Which process increases muscle force by rapidly stimulating a muscle before it has fully relaxed, resulting in greater tension?

Accepted Answer

Wave summation

Anatomy & Physiology Study Guide: Skeletal and Muscular Systems

Study Guide - Practice Questions

Study Guide - Flashcards