REVIEW

Muscular System

What are the 3 types of muscle

tissue?

SkeletalCardiacSmooth

On which type of muscle tissue would

you observe striations?

Skeletal muscle tissueCardiac muscle tissue

What type of tissue is specialized for the

conduction of electrical impulses?

Neural (nervous) tissue

surrounds individual skeletal

muscles.

Epimysium

surrounds individual muscle cells

(fibers)?

Endomysium

surrounds muscle

fascicles.

Perimysium

What is the cell membrane of a skeletal muscle

called?

Sarcolemma

What structure is the storage site for

Ca2+?

Terminal cisternae

Active sites on the actin are blocked by

when a muscle is at rest.

Tropomyosin molecules

What are the contractile units of a

skeletal muscle?

Sarcomeres

In response to the arrival of an from the

transverse tubules, Ca2+ is released from the .

Action potentialSarcoplasmic reticulum

= a single contraction?

Twitch

During contraction, myosin heads interact with actin filaments,

forming what?

Cross-bridges

The arrival of an action potential at the synaptic

terminal releases into the synaptic

cleft.

Acetylcholine (ACh)

Put the following steps of muscle

contraction in order from first to last:

1. Myosin cross-bridges bind to the actin2. Calcium ion is released from the SR 3. The free myosin head splits ATP4. The myosin head pivots toward the center of

the sarcomere5. The myosin head binds an ATP molecule and

detaches from actin 6. Calcium ion binds to troponin

A muscle producing peak tension with rapid cycles

of contraction & relaxation is said to be in .

Incomplete tetanus

What are the 3 phases of a twitch?

Latent periodContraction periodRelaxation operiod

A stair-step increase in twitch tension is

known as…?

Treppe

Repeated stimulations before the end of the

relaxation phase causes increasing tension =

.

Wave summation (summation of twitches)

occurs if stimulation frequency is

high enough that a muscle never begins to relax

Complete tetanus

*produces a continuous contraction

Increasing tension that is produced by increasing the number of motor units =

.

Recruitment

An contraction occurs when the muscle

shortens in length.

Isotonic

A muscle fiber returns to resting length by what 3

mechanisms?

Opposing muscle contractionsElasticGravity

What is the storage molecule for excess

ATP?

Creatine phosphate

CP + ADP C + ATP

contract quickly, have a large diameter & glycogen

reserves, & few mitochondria.

Fast fibers

An contraction occurs when the muscle develops tension, but is

prevented from changing length.

Isometric

What is the primary energy source of resting muscles?

Aerobic metabolism

*breaks down fatty acids; produces 34 ATP molecules

A helps to start motion or

stabilize the origin of the agonist.

Fixator

What can happen to muscles as lactic acid

builds up and they become exhausted?

Fatigue

contract slowly, have a small diameter,

contain myoglobin, & have

more mitochondria

Slow fibers

What is the primary energy source for peak

muscular activity?

Anaerobic glycolysis

*breaks down glucose from glycogenby-product = lactic acid (forms due to

accumulation of pyruvic acid)

Name 4 of the effects of aging on the

muscular system.

1. Skeletal muscle fibers become smaller in diameter

2. Skeletal muscles become less elastic3. Tolerance for exercise decreases4. The ability to recover from muscular

injuries decreases

Center resistance between applied

force and fulcrum

Second-class lever

In which type of muscle would you expect to find

slow fibers?

Red muscle

What is the difference between muscle hypertrophy &

atrophy?

*Hypertrophy increased muscle growth

from heavy training*Atrophy reduction in

muscle size, tone, & power due to lack of use

Center applied force between resistance

and fulcrum

Third-class lever

Moving point of attachment =

.

Insertion

A(n) 1 produces a particular movment, while

a(n) 2 opposes that movement.

1: Agonist (prime mover)2: Antagonist

Center fulcrum between applied force

and resistance

First-class lever

*example: see-saw

Fixed point of attachment =

.

Origin

What is a smaller muscle that assists a larger muscle called?

Synergist

What two points does myosin attach to in a

sarcomere?

M-line and titin

What does actin attach to in the

sarcomere?Z-line

The lengthening of a muscle is what type

of contraction?

eccentric

What is the area where the axon and

the muscle meet called?

Neuromuscular junction

What ezyme removes the neurotransmitter Ach from the synaptic

cleft?

AChE

GOOD LUCK!

UNIT 3 TEST TOMORROW!OVER CHAPTERS 4 and 10

STUDY, STUDY, STUDY!!!