Ch.10 And 11 - Muscles

Front 1

Functional characteristics of muscle.

Back 1

1. contractility - shorten
2. excitability - electrical signals
3. extensibility - stretch
4. elasticity - return to normal shape

Front 2

aponeuroses

Back 2

Broad, flattened tendon.

Front 3

fascia

Back 3

Dense sheet of CT that lines the body wall and limbs.

Front 4

somatic motor neurons

Back 4

Neurons whose axons innervate skeletal muscle.

Front 5

sarcoplasm contains...

Back 5

myoglobin and glycogen

Front 6

components of a myofibril

Back 6

1. Contractile proteins --> actin and myosin
2. Regulatory --> troponin and tropomyosin
3. Structural --> titan and dystrophin

Front 7

tropomyosin

Back 7

Covers the myosin binding sites on actin.

Front 8

troponin

Back 8

Attached to tropomyosin, binds with calcium and pulls tropomyosin off binding sites.

Front 9

dystrophin

Back 9

Anchors the myofibrils to the sarcolemma (only at the ends)

Front 10

titan

Back 10

Huge elastic protein that anchors the thick filament to the z-disc and resists overstretching.

Front 11

sarcoplasmic reticulum

Back 11

Encircle each myofibril, stores calcium ions. When electrical signal goes down t-tubule to SR, Ca is released and contraction occurs.

Front 12

What shortens/disappears during a contraction?

Back 12

H zone disappears and I zone narrows

Front 13

motor unit

Back 13

A single somatic motor neuron and all the muscle fibers it innervates.

Front 14

Components of the Neuromuscular Junction

Back 14

1.Axon terminal (terminal boutons)
2. Sarcolemma of muscle fiber (with junctional folds and Ach receptors)
3. Synapatic cleft

Front 15

Characteristics of slow oxidative fiber (type 1)

Back 15

High myoglobin content, aerobic, high fatigue resistance, red, small fibers

Front 16

Function of slow oxidative fibers

Back 16

Maintaining posture and endurance activities

Front 17

Characteristics of fast oxidative fibers (type IIa)

Back 17

High myoglobin content, aerobic and anaerobic, intermediate fatigue resistance, pink, intermediate fibers

Front 18

Function of fast oxidative fibers (type IIa)

Back 18

Walking, sprinting

Front 19

Characteristics of fast-glycolytic fibers (type IIb/IIx)

Back 19

Low myoglobin content, anaerobic, low fatigue resistance, white, large fibers

Front 20

Function of fast-glycolytic fibers (type IIb/IIx)

Back 20

Rapid, intense movements of very short duration

Front 21

lever

Back 21

bone

Front 22

fulcrum

Back 22

joints

Front 23

effort

Back 23

muscle contraction

Front 24

load

Back 24

bones, other soft tissue, anything you're trying to pick up or move

Front 25

When the fulcrum is closer to the load...

Back 25

...greater mechanical advantage.

Front 26

When fulcrum is farther from the load...

Back 26

... greater mechanical disadvantage.

Front 27

Convergent muscle

Back 27

Fascicles converge to a tendon of insertion, triangular looking.
(ex. pectoralis major)

Front 28

Parallel muscle

Back 28

Fascicles run parallel to the long axis of the muscle, fusiform(ex. biceps brachii), strap-like (ex. sartorius)

Front 29

Circular muscle

Back 29

Circular rings, always found at external body openings (sphincters).

Front 30

Pennate muscle

Back 30

Short fascicles that attach obliquely to a tendon that runs the length of the muscle (penna = feather).

Front 31

Unipennate example

Back 31

Extensor digitorum longus ( one side of tendon)

Front 32

Bipennate example

Back 32

Rectus femoris (both sides of tendon)

Front 33

Multipennate example

Back 33

Deltoid (on multiple sides of tendon)

Front 34

Muscle crossing anterior side of a joint has which action?

Back 34

Flexion

Front 35

Muscle crossing posterior side of a joint has which action?

Back 35

Extension

Front 36

Muscle crossing lateral side of a joint has which action?

Back 36

Abduction

Front 37

Muscle crossing medial side of a joint has which action?

Back 37

Adduction