Chapter 8 Muscular System - Review Questions

Muscle tone

a state of sustained, partial contraction of muscles that is necessary to maintain posture

The chemical that is necessary for the transmission of an impulse from a nerve to a muscle fiber is

acetylcholine

The energy used in muscle contraction is supplied by the decomposition of

adenosine triphosphate

A person feels out of breath after vigorous exercise because of oxygen debt. Explain this phenomenon

Anaerobic respiration increases during strenuous activity

refers to a decrease in the size of strength of a muscle

Atrophy

A substance that stores energy released when ATP is synthesized is

Creatine Phosphate

The kind of energy that muscles use to contract is

Heat

After prolonged muscle use, muscle fatigue occurs due to an accumulation of

Lactic Acid

Two types of smooth muscle are

Multiunit muscle and visceral muscle

Smooth body movements depend on____ giving way to prime movers

antagonists

A flat sheet of tendon like material that anchors a muscle or connects it with the part of the muscle that moves

aponuerosis

The ion necessary to link myosin and actin is

calcium

Peristalsis is due to what characteristic of smooth muscle

capacity of smooth muscle fibers to excite each other

movement in the inferior direction

depression

the movement in a superior direction

elevation

increasing the angle of a joint

extension

An individual skeletal muscle is separated from adjacent muscles by

fascia

Layers of fibrous connective tissues that separate increasing the angle of a joint individual skeletal muscle

fascia

decreasing the angle of a joint

flexion

The attachments of muscle to a relatively fixed part is called the ____; the attachment to a relatively movable part is called the _____

origin; insertion

The period of time between a stimulus to a muscle response is called

latent period

An injury in which few muscle fibers are torn but the fascia is left intact is called

mild muscle strain

A motor neuron and the muscle fibers it controls are called a

motor unit

The characteristic striated appearance of skeletal muscle is due to the arrangements of alternating protein filaments composed of ___ and ___

myosin and actin

The union between a nerve fiber and a muscle fiber is the

neuromuscular junction

The strength of a muscle contraction in response to different levels of stimulation is determined by the

number of motor units stimulated

When the cross-bridge of the myosin molecule forms linkages with actin filaments, the result id

shortening of the muscle fiber

The muscle that assists movement

synergists

connects muscle to bone

tendon

Smooth muscle contracts more slowly than ____ after stimulation

Skeletal muscle

List the tissues found in the skeletal muscle

Skeletal muscle tissue, nervous tissue, blood and connective tissues.

Layers of connective tissues extending into the muscle to form partitions between muscle bundles are continuous with attachments of muscle to periosteum called

Tendons

The minimal strength stimulus needed to elcit contraction of a single muscle fiber is called a

Threshold stimulus