Muscular

The prime mover of arm abduction is the ________ muscle. A) trapezius B) deltoid C) latissimus dorsi D) quadratus lumborum

B) deltoid

Smooth muscle cells are ________. A) multinucleate B) involuntary C) branched D) striated E) cylindrical

B) involuntary

One neuron and all the skeletal muscles it stimulates is known as a ________. A) sarcoplasmic reticulum B) motor unit C) synaptic cleft D) neuromuscular junction

B) motor unit

Anaerobic glycolysis occurs without ________. A) ATP B) oxygen C) lactic acid D) carbon dioxide E) glucose

B) oxygen

Which of the following is an example of an isometric contraction? A) shaking the head as to say "no" B) pushing against an immovable wall C) bending the elbow D) rotating the arm E) nodding the head as to say "yes"

B) pushing against an immovable wall

Acetylcholine is ________. A) an ion pump on the postsynaptic membrane B) a source of energy for muscle contraction C) a component of thick myofilaments D) an oxygen-binding protein E) a neurotransmitter that stimulates skeletal muscle

E) a neurotransmitter that stimulates skeletal muscle

Which muscle group includes the biceps femoris, semimembranosus, and semitendinosus? A) abdominal muscles B) quadriceps group C) adductor group D) fibularis muscles E) hamstring group

E) hamstring group

Which of the following is NOT a function of the muscular system? A) production of movement B) maintenance of posture C) stabilization of joints D) generation of heat E) hematopoiesis

E) hematopoiesis

An elaborate and specialized network of membranes in skeletal muscle cells that function in calcium storage is the ________. A) sarcolemma B) mitochondria C) intermediate filament network D) myofibrillar network E) sarcoplasmic reticulum

E) sarcoplasmic reticulum

Contractions in which muscles shorten and produce movement are known as ________. A) isotonic contractions B) twitches C) isometric contractions D) resistance exercises

A) isotonic contractions

The plasma membrane of a skeletal muscle cell is called the ________. A) sarcolemma B) sarcomere C) myofilament D) sarcoplasm E) sarcoplasmic reticulum

A) sarcolemma

The gap between the motor neuron and the muscle fiber it supplies at the neuromuscular junction is called the ________. A) synaptic cleft B) motor unit C) cross bridge D) H zone

A) synaptic cleft

Which of these events must occur first to trigger the skeletal muscle to generate an action potential and contract? A) sodium ions rush into the cell B) acetylcholine (ACh) causes temporary permeability to sodium C) diffusion of potassium ions out of the cell D) operation of the sodium-potassium pump E) acetylcholinesterase (AchE) breaks down acetylcholine (ACh)

B) acetylcholine (ACh) causes temporary permeability to sodium

Endomysium covers ________. A) fascicles of muscle cells B) an entire muscle C) an individual muscle cell D) myofibrils E) smooth muscle only

C) an individual muscle cell

Muscles that perform opposite actions to one another are termed ________. A) synergists B) prime movers C) antagonists D) fixators

C) antagonists

Muscle tissue has the ability to shorten when adequately stimulated, a characteristic known as ________. A) elasticity B) irritability C) contractility D) extensibility

C) contractility

The condition of skeletal muscle fatigue can be best explained by ________. A) the all-or-none law B) the inability to generate sufficient quantities of ATP due to feedback regulation of synthesis C) insufficient intracellular quantities of ATP due to excessive consumption D) a total lack of ATP E) inadequate numbers of mitochondria

C) insufficient intracellular quantities of ATP due to excessive consumption

A motor neuron and all of the skeletal muscle fibers it stimulates are termed a ________. A) myofilament B) synaptic cleft C) motor unit D) neuromuscular junction E) neurotransmitter

C) motor unit

The muscle that closes each eye is the ________. A) orbicularis oris B) frontalis C) orbicularis oculi D) zygomaticus

C) orbicularis oculi

The movement opposite to abduction is ________. A) flexion B) rotation C) circumduction D) adduction E) supination

D) adduction

What is the main function of the quadriceps group? A) arm flexion B) hand supination C) thigh abduction D) knee extension E) foot inversio

D) knee extension

Which one of the following is NOT a criterion generally used in naming muscles? A) relative size of the muscle B) number of origins of the muscle C) shape of the muscle D) method of attachment of the muscle to bone E) action of the muscle

D) method of attachment of the muscle to bone

The point of muscle attachment to an immovable or less movable bone is known as the ________. A) innervation B) action C) insertion D) origin

D) origin

The gap between the axon terminal of a motor neuron and the sarcolemma of a skeletal muscle cell is called the ________. A) motor unit B) sarcomere C) neuromuscular junction D) synaptic cleft E) cross bridge

D) synaptic cleft