muscle parts

What muscle layer surrounds an

individual muscle fiber?

Endomycium

What muscle layer surrounds a fascicle

(bundle of muscle fibers)

Perimycium

What muscle layer surrounds a bunch

of fascicles?

Epimycium

What muscle layer becomes the

tendon?

Epimycium (becomes the tendon)

What is the MUSCLE FASCIA

loose fibrous connective tissue on the outside of the muscle.

What does the MUSCLE FASCIA do?

It creates a slippery surface for muscles to rub

against each other.

What is an aponeurosis?

A modified tendon.

It usually inserts just under the skin. This occurs in the palm and scalp.

What is a muscle stem cell called?

MYOBLAST

What 2 things are needed for muscle

contraction?

NERVE SIGNAL and CALCIUM

What is a MOTOR UNIT?

A single neuron and all of the muscle fibers on which

it synapses

Muscle myofibrils contain what two

proteins?

Actin and myosin

What is it that contracts in muscle?

sarcomere

What is the basic structural and

functional unit of skeletal muscle?

Sarcomere

What is a single muscle cell called?

Muscle fiber or myofiber

What are the two types of

myofilaments?

Actin (thin) and myosin (thick)

Do actin and myosin shorten?

No, they just slide past each other

When does the sliding filament

mechanism begin?

When calcium ions bind to the troponin (myofilament).

Which myofilament does calcium bind

onto?

The thin (actin filament)

Where is calcium stored for muscle

contraction?

Sarcoplasmic reticulum

To which myofilament does ATP attach

in a muscle fiber?

the myosin filament

What is required for muscle relaxation?

ATP

What neurotransmitter is used for

contraction of skeletal muscle, and on

what region does it land on?

Acetylcholine, which is released onto the

region known as the end plate (helecopter landing pad)

What two proteins wrap around actin?

Tropomyosin and troponin

What specific molecule on actin is the

binding site for calcium?

Troponin

What covers the actin filament when

muscle is relaxed?

Tropomyosin and troponin

Which protein blocks the attachment

site for myosin heads?

Tropomyosin

What size motor unit will supply less

strength and more precision?

Small motor unit