Question 10 of 50

Which property of muscle tissue is defined as its ability to be stretched or extended?

What is a key structural difference between skeletal muscle fibers and cardiac muscle fibers?

Which layer of connective tissue wraps around an entire skeletal muscle?

What is the term for a bundle of muscle fibers organized by a middle layer of connective tissue called the perimysium?

What is the specialized smooth endoplasmic reticulum in a muscle fiber that stores, releases, and retrieves calcium ions?

Which structure is considered the functional unit of a skeletal muscle fiber, defined as the region from one Z-disc to the next?

What is the function of the T-tubules in a skeletal muscle fiber?

What neurotransmitter is released at the neuromuscular junction (NMJ) to initiate skeletal muscle contraction?

According to the sliding filament model, what is the first step that initiates muscle contraction after an action potential reaches the muscle fiber?

What is the function of the protein tropomyosin in a resting skeletal muscle?

In the cross-bridge cycle of muscle contraction, what is the direct role of ATP binding to the myosin head?

What is the direct physiological cause of rigor mortis, the rigidity observed in skeletal muscles soon after death?

For approximately how long can creatine phosphate-derived ATP power muscle contraction?

In the absence of oxygen, what is pyruvic acid converted to, which may contribute to muscle fatigue?

Approximately how many ATPs are produced per molecule of glucose via aerobic respiration compared to anaerobic glycolysis?

What is meant by the term 'oxygen debt' following intense muscle activity?

Which of the following events initiates the relaxation of a skeletal muscle fiber?

What is the term for the increase in muscle mass and bulk resulting from the increased production of sarcomeres and myofibrils within muscle fibers?

Duchenne muscular dystrophy (DMD) is a progressive weakening of skeletal muscles caused by a lack of which protein?

Which type of skeletal muscle contraction involves the muscle producing tension without changing the angle of a skeletal joint, such as when attempting to lift a weight that is too heavy?

Lowering a hand weight in a slow and controlled manner, where muscle tension diminishes and the muscle lengthens, is an example of what type of contraction?

Where in the human body would you expect to find small motor units, where a single motor neuron supplies a small number of muscle fibers?

What is the term for the increase in muscle contraction strength that occurs as more motor units are enlisted to activate larger muscle fibers?

At what percentage of its resting length does a sarcomere produce the maximal tension?

What is the first phase of a muscle twitch, during which the action potential is being propagated along the sarcolemma but contraction has not yet occurred?

When a muscle fiber is stimulated while a previous twitch is still occurring, the second twitch will be stronger. What is this response called?

What is the state of muscle contraction called when the stimulus frequency is so high that the relaxation phase disappears completely, leading to continuous contraction?

What is the term for the small amount of contraction that allows muscles to stabilize joints and maintain posture, even when not producing movement?

Which type of skeletal muscle fiber contracts relatively slowly and uses aerobic respiration to produce ATP, making it highly resistant to fatigue?

Which characteristic is typical of fast glycolytic (FG) fibers?

Why do slow oxidative (SO) muscle fibers have a red color?

Fast oxidative (FO) fibers, which produce more tension than SO fibers but are more fatigue-resistant than FG fibers, are primarily used for which type of movement?

What is the primary effect of endurance exercise on slow oxidative (SO) muscle fibers?

What is the term for irreversible, age-related muscle atrophy where muscle fibers die and are replaced by connective and adipose tissue?

Resistance exercise, which requires large amounts of FG fibers, primarily affects muscles by increasing the formation of what structures, thereby increasing muscle thickness?

What is the main function of erythropoietin (EPO) when used as a performance-enhancing substance by endurance athletes?

Which of the following is a characteristic feature of cardiac muscle tissue?

What two structures, important for cardiac muscle contraction, are contained within intercalated discs?

What is the term for the ability of specialized cardiac muscle cells, called pacemaker cells, to self-excite and fire action potentials on their own at set intervals?

How are smooth muscle fibers typically described in terms of shape and number of nuclei?

In a smooth muscle fiber, which regulatory protein does Ca++ bind to in order to initiate contraction, as it does not contain troponin?

What is the key difference between single-unit smooth muscle and multiunit smooth muscle?

What is the name for the subset of cross-bridges in some smooth muscles that can remain linked together for a prolonged period without the need for ATP, allowing for the maintenance of muscle tone?

Unlike skeletal and cardiac muscle, smooth muscle can divide to produce more cells. What is this process called?

Most muscle tissue of the body, excluding those of the head and limbs, develops from which embryonic structures that arise from paraxial mesodermal cells?

During early development, embryonic myoblasts fuse to form a syncytium, or a continuous cytoplasm with many nuclei. What is this structure called?

What is the function of satellite cells in skeletal muscle tissue?

When a muscle is damaged to a greater extent than can be repaired by satellite cells, the muscle fibers are replaced by scar tissue. What is this process called?

Which type of muscle tissue has the greatest ability to regenerate and repair itself, utilizing stem cells called pericytes found in some small blood vessels?