Chapter 8: The Muscular System

Two types of smooth muscles are?

Viscera smooth and Multiunit smooth

Muscle tone refers to?

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?

Acetylcholine

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

Adenisine Triphosphate

A person feels out of breath after vigorous exercise because of oxygen debt. Which of the following statements explains this phenomenon? Anaerobic respiration increases during strenuous activity Lactic acid is metabolized more efficiently when body is at rest Conversion of lactic acid to glycogen occurs in the liver and requires energy Priority in energy use is given to ATP synthesis?

Anaerobic respiration increases during strenuous activity Conversion of lactic acid to glycogen occurs in the liver and requires energy Priority in energy use is given to ATP synthesis?

Smooth body movements depend on ____ giving way to prime movers

Antagonists

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

Aponeuroses

The muscle that compresses the cheek inward?

Buccinator

The attachment of a muscle to a relatively fixes part is called the ______

Origin

Peristalsis is due to which of the follow Characteristics of smooth muscle?

Capacity of smooth muscle fibers to excite each other Rhythmicity

A substance that stores energy released when stores of the substance in number 10 are in low supply is?

Creatine Phosphate

Atrophy refers to a increase/decrease in muscle size and strength

Decrease

The muscle that abducts the upper arm and can both flex and extend the humerus is the?

Deltoid

The heaviest muscle in the body, which serves to straighten the leg at the hip during walking is the?

Gluteus Maximus

The attachment to a relatively movable part is?

Insertion

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

Lactic acid

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

Latent Period

The band of tough connective tissue that extends from the xiphoid process to the symphysis pubis and serves as an attachment for muscles of the abdominal wall is the?

Linea alba

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

Mild muscle strain

A motor neuron and the muscle fiber it controls are called a?

Motor Unit

Which of the following muscle changes will occur in response to an exercise like swimming that produces relatively weak muscle contraction?

Muscle will be able to resist fatigue Increased numbers of mitochondria and capillaries will form

The characteristics striated appearance of skeletal muscle is due to the arrangement of alternating protein filaments composed of _____ and _____

Myosin and Actin

The union between a nerve fiber and 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 unites stimulated

Smooth muscle contracts slower/faster than skeletal muscle following stimulation

Slower

The ion necessary to link myosin and action?

Calcium

An individual skeletal muscle is separated from its adjacent muscles by?

Fascia

Tissues found in skeletal muscle?

Fascia, Epimysium, Perimysium

Impulses travel relatively rapidly/slowly through cardiac muscle

Rapidly

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

Shortening of the muscle fiber

The muscle that moves the head to one side is the?

Sternocleidomastoid Splenius capitis Semispinalis capitis

The minimal strength stimulus needed to elicit contraction of a single muscle fiber is called an?

Threshold stimulus