Chapter 10 A&P 1 practice questions

The term aponeurosis refers to a A. broad, flat, sheetlike tendon B. band of connective tissue that encloses entire groups of tendons C. connective tissue sheath that encloses several tendons D. thickened part of a muscle

broad, flat, sheetlike tendon

A sustained muscle contraction without partial relaxation between stimuli is called A. unfused (incomplete) tetanus B. fused (complete) tetanus C. recruitment D. recovery oxygen uptake

fused (complete) tetanus

The enzyme acetylcholinesterase causes A. ATP to break down to ADP B. acetylcholine to break down C. troponin to bind to tropomyosin D. breakdown of pyruvic acid to lactic acid

acetylcholine to break down

Myofibrils are composed primarily of a. actin and myosin b. troponin c. ATP d. tropomyosin

actin and myosin

The ______________________________________ is responsible for the striations of striated muscle. A. troponin-tropomyosin interaction B. hydrolysis of ATP C. position of H zones D. alternating of A bands and I bands

alternating of A bands and I bands

A muscle fascicle is surrounded by a. sarcomysium b. endomysium c. epimysium d. perimysium

perimysium

Muscles generate heat, stabilize the body positions and: A. line organs that open to the outside B. coordinate homeostatic functions for the body C. protect the body from invading organisms D. produce body movements

produce body movements

An increase in the number of active motor units in a muscle is called A. treppe B. peristalsis C. wave summation D. recruitment

recruitment

Calmodulin is involved in the contraction of: A. smooth muscle B. skeletal muscle C. striated muscle D. cardiac muscle

smooth muscle

When examined under a microscope, in which type of muscle tissue are myofibrils not apparent? a. skeletal muscle b. cardiac muscle c. atrophied muscle d. smooth muscle

smooth muscle

Which of the following does NOT have T-tubules? A. skeletal muscle B. smooth muscle C. striated muscle D. cardiac muscle

smooth muscle

Creatine phosphate A. breaks down ATP B. activates ATPase C. supplies energy for synthesis of ATP D. supplies energy to break ATP into ADP

supplies energy for synthesis of ATP

The following is a list of events in random order that occur in the contraction of skeletal muscle. Identify which of the subsequent letters represents the correct chronological order of these events. 1. Ca2+ binding to troponin 2. release of Ach at the neuromuscular junction 3. coming together of Z discs 4. depolarization of sarcolemma 5. myosin head attaching to myosin binding site on actin 6. depolarization of T-tubules

2, 4, 6, 1, 5, 3

For the initiation of an action potential that starts contraction in skeletal muscle fiber: A. Ach must bind to receptors on the motor end plate B. Ach must bind to the neurolemma of the somatic neuron C. acetylcholinesterase must break down Ach at the synapse D. K+ must flow into the neurolemma

Ach must bind to receptors on the motor end plate

Which of the following properties of muscle tissue is its ability to generate tension to do work? a. extensibility b. elasticity c. contractility d. excitability

contractility

Which type of muscle tissue is involuntary, slow in contracting, and able to regenerate considerably better than other types of muscle? A. skeletal muscle B. smooth muscle C. cardiac muscle D. striated muscle

smooth muscle

Cardiac muscle fibers are attached to one another at A. sarcomeres B. T-tubules C. intercalated discs D. A bands

intercalated discs

Muscle contraction is triggered by impulses carried over A. sensory neurons B. afferent neurons C. motor neurons D. myofibrils

motor neurons

A motor neuron and all the muscle fibers it stimulates form a A. motor end plate B. neuromuscular junction C. motor unit D. muscle

motor unit

If Ach is not released at the neuromuscular junction then: A. anaerobic respiration occurs B. aerobic respiration occurs C. acetylcholinesterase will be broken down D. muscle contraction will not happen

muscle contraction will not happen

In tetanus A. muscles wither away B. muscles undergo sustained contractions C. Ca2+ levels drop too low to sustain contractions D. muscles tire due to build up of ATP

muscles undergo sustained contractions

The elevated use of oxygen after exercise is called A. anaerobic respiration B. recovery oxygen uptake C. central fatigue D. asthma

recovery oxygen uptake

Excitability refers to the ability of a cell to a. return to its original length after stretching b. shorten c. assume a desired shape regardless of how much it has been stretched d. respond to a stimulus by producing an electrical signal

respond to a stimulus by producing an electrical signal

Elasticity refers to the ability of a muscle fiber to a. shorten b. stretch c. respond to a stimulus d. return to original shape after contracting or stretching

return to original shape after contracting or stretching

In an isometric contraction A. the muscle contracts but does not shorten B. the muscle moves the bone to reduce the angle of a joint C. the muscle increases in length during the contraction D. no energy is expended because nothing moves

the muscle contracts but does not shorten

When ATP attaches to the myosin head A. the head detaches from actin B. the head attaches to troponin C. Ca2+ reacts with the ATP D. actin and myosin both shorten

the myosin head detaches from actin

The binding of Ca2+ to __________________ starts the contraction cycle. A. tropomyosin B. ATP C. troponin D. sarcoplasmic reticulum

troponin

When calcium ion concentration in the sarcoplasm is low, the A. myosin stretches and the muscle relaxes B. actin detaches from the Z discs C. troponin-tropomyosin complex slides back over the myosin binding sites D. muscle cell membrane releases acetylcholine

troponin-tropomyosin complex slides back over the myosin binding sites

Which of the following links thin filaments to the sarcolemma? a. dystrophin b. myomesin c. titin d. myosin

dystrophin

Calcium ions move from the cytoplasm (sarcoplasm) into the sarcoplasmic reticulum because of the action of A. active transport pumps in the sarcoplasmic reticulum membrane B. ion diffusion channels in the sarcolemma C. myosin binding sites in the sarcoplasmic reticulum membrane D. acetylcholine receptors on the cell surface

active transport pumps in the sarcoplasmic reticulum membrane

The outermost layer of connective tissue surrounding a skeletal muscle is the A. epimysium B. perimysium C. endomysium D. sarcomysium

epimysium

In the liver, some of the lactic acid is converted to A. glycogen B. myoglobin C. ATP D. acetylcholinesterase

glycogen

Smooth muscle differs from skeletal because smooth muscle A. has dense bodies instead of Z discs B. is multi-nucleated C. is striated D. has a lot of sarcoplasmic reticulum

has dense bodies instead of Z discs

The motor end plate is part of a A. motor neuron B. skeletal muscle cell at the synapse C. cardiac muscle cell at the intercalated disc D. smooth muscle cell when two cells meet

skeletal muscle cell at the synapse

The sarcoplasmic reticulum a. is the cell membrane around each muscle fiber. b. stores Ca2+ when the fiber is at rest. c. opens to the outside through the sarcolemma. d. produces ATP for muscle contraction.

stores Ca2+ when the fiber is at rest.

When smooth muscles are stretched they contract, but within a short time the tension decreases. This is called A. passive contraction B. isotonic eccentric contraction C. stress-relaxation response D. incomplete tetanus

stress-relaxation response