Human Anatomy and Physiology- Sections 10.8-10.10

As a result of physical inactivity, muscle cell and myofibrils will be reduced in size and number, respectively. This condition is known as __________. hypertrophy atrophy hyperplasia trophy

atrophy

Unlike skeletal muscles, cardiac muscle fibers do not require autonomic stimulation to depolarize and contract. This property is known as ___________. eurhythmic automaticity multiunit hypertrophy

automaticity

The wave-like contraction created by smooth muscle cells is known as ________. P wave peristalsis T wave short wave

peristalsis

Extensive blood vessels, mitochondria, and myoglobin are found in the greatest concentration in __________. fast fibers intermediate fibers slow fibers type II fibers

slow fibers

The type of skeletal muscle fiber best suited for endurance-type activities is __________. fast fibers slow fibers intermediate fibers All three fiber types are suited to endurance-type activity.

slow fibers

Which of the following may cause muscle atrophy? A lack of regular stimulation of muscle fibers Wearing a cast on a broken limb Paralysis All of the listed responses are correct.

All of the listed responses are correct.

What is the term for the ability of cardiac muscle cells to contract without neural stimulation? Rigor Automaticity Plasticity Oxygen debt

Automaticity

In smooth muscle cells, calcium binds to which regulatory protein to initiate contraction? Troponin Calmodulin Tropomyosin Actin

Calmodulin

The cardiovascular system uses which types of muscle? Cardiac and smooth Cardiac, smooth, and skeletal Smooth and skeletal Skeletal and cardiac

Cardiac and smooth

Which of the muscle fiber types is best adapted for a rapid contraction but fatigues easily? Slow fibers Intermediate fibers Fast fibers Tight fibers

Fast fibers

What structure is responsible for the spread of action potential between visceral smooth muscle cells? Gap junctions Desmosomes Tight junctions Hemidesmosomes

Gap junctions

What is the name of the structure that contains gap junctions and desmosomes and joins the plasma membranes of two cardiac muscle cells together? T tubules Dense bodies Intercalated discs Sarcoplasmic reticulum

Intercalated discs

Which of the following is NOT a characteristic of smooth muscle tissue? Absence of sarcomeres Presence of dense bodies Presence of spindle-shaped cells Presence of striations

Presence of striations

Marathon runners rely on which muscle fiber type for endurance? Fast fibers Intermediate fibers Tight fibers Slow fibers

Slow fibers

What type(s) of muscle tissue do(es) NOT contain sarcomeres? All of the listed responses are correct. Cardiac Smooth Skeletal

Smooth

Structurally, how do smooth muscle cells differ from skeletal muscle cells? Smooth muscle cells lack myofibrils and sarcomeres. Smooth muscle cells possess striations. Smooth muscle cells contain many nuclei. Smooth muscle cells contain a network of T tubules.

Smooth muscle cells lack myofibrils and sarcomeres.

What is a characteristic of cardiac muscle that is NOT true of skeletal muscle? They lack terminal cisternae. They don't require calcium to trigger the contraction. They don't contract by the sliding filament mechanism. They don't have T tubules.

They lack terminal cisternae.

Smooth muscle contractions in the respiratory passageways cause __________. no change in the relative airflow a decrease in diameter, making it harder for air to flow immediate death an increase in diameter, making it easier for air to

a decrease in diameter, making it harder for air to flow