Chapter 9&10 A&P Test

Muscles

Muscle fibers AKA ______ ______

• Muscle cells

What are prefixes that indicate a muscle?

• 1) Myo/Mys

• 2) Sacro (flesh)

4 characteristics of muscle tissue

• 1) Excitablility

• 2) Contractility

• 3) Extensibility

• 4) Elasticity

Excitable

• (Responsiveness), recieve & respond to a stimulus

Contractility

• to get shorter

Extensibility

• stretch/extend beyond resting length

Elasticity

• Recoil & go back to orginal resting spot

What are the muscle functions?

• Produce movement

• Maintain posture & body postition

• Stabalize joints

• Generate body heat

Muscle cells use the most ___

• ATP

Flexation

• When you flex a muscle it decreases the angle of a joint

Extension

• increases

Abduction

• Moving things away from the center of the body

Adduction

• to move towards the center of the body

Each seperate muscle is considered to be an _________

• Organ

There are ___ anterior and __ posterior muscles on the test to know

• 5 & 5

External Oblique (Orgin, Insertion, Primary Action)

• Outer surface of lower eight ribs (fleshy)

• Insertion: Linea Alba

• Flexes vertrabl column and compress abdominal wall & rotating trunk and flexing laterally

Deltoid (Orgin, Insertion, Primary Action)

• Shoulder-blade / collarbone

• Insertion: Humerous

• Primer mover of arm abduction when all its fibers contract simultaneously

Pectoralis Major (Orgin, Insertion, Primary Action)

• sternum cartiliage of ribs (upper 6)

• Insertion: Long bone of upper arm (bicipital groove)

• Adducts and medially rotates arm

Biceps Brachii (Orgin, Insertion, Primary Action)

• Orgin: Short + long branch of muscle

• Insertion: radial tuberosity (hollow part of elbow)

• Flexes and supinates the forearm

Abductor Longus (Orgin, Insertion, Action)

• Pubis near pubic symphis

• Insertion: linea aspera (middle-third of femoral shaft)

• Adducts, flexes, and medially rotates thigh

Latissimus Dorsi

• Under scalpula

• Insertion: Intertubercular sulcus of humerous

• Primer mover of arm extension; powerful arm adductor, medially rotates arm at shoulder

Triceps Brachii

origin: scapula, numerous, humeral shaft

insertion: olecranon of ulna

function: powerful forearm extensor

Extensor Carpi Radialis Longus

Origin: ridge of humerus

Insertion: 2nd metacarpal (wrist)

Function: extends & abducts hand

Semimembranosus

Origin: round bone at the bottom of your pelvis

Insertion: Inner part of shinbone

Function: extends thigh & flexes leg

Gastrocnemius

Origin: Back of the knee joint

Insertion: Achilles tendon (heel bone)

Function: plantar flexes foot

Epimysium

• top covering of a muscle (at the end becomes a tendon)

Fascicles

• group of individual muscle cells (perimysium surrounds it)

Enaomysium

• connective tissue between cells

Aponeurosis

• muscle attached to muscle

Sarcolemma

• plasma membrane

The cytoplasm of a muscle cell is called what?

• Sarcoplasm

What is in sarcoplasm?

• Glycosomes (stored glycogen for ATP)

• Myoglobin (red pigment that carries oxygen)

Myofibrils

• Muscle fibers contain lots of rod-like structures

• Alternating light/dark bands

Long red lines vs blue lines

• Long red = thick filament

• Blue = thin filaments

When a muscle contracts the _________ are pulling together

• filaments

H-Zone

• Thick filaments ONLY

• Disappears when a muscle contracts

I-band

• 100% thin filaments

A-band

• Entire width of thick filaments, even where it overlaps

Z-line/disc

• anchor point

Sarcomere

• Individual contractile unit of a muscle

M-line

• Anchor point for thick filaments

Each _____ filament is surrounded by __ actins (thin)

• Thick, 12

Sarcoplasmic Reticulum

• Surrounds mycrofibiril “like a sleeve”

T-tubule

• At the A & I bond junction

• Elongated tube

SUMMARY OF STEPS ON MUSCLE CONTRACTION

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Axon terminal has _______ channels

• Calcium

Synaptic cleft has ________________ channels?

• Sodium-Potassium

An enzyme that breaks acetylcholine (ACh) into 2 parts

• ACHE

Be able to label Neuromuscular Junction

• Page 290

Polarized

• To separate potassium and sodium ions

Depolarized

• Allowing it to return to orignial flow

Motor unit

• One motor neuron and all the muscle fibers it innervates or supplies

Very small _______ period ( _____ mins) where the muscle isn’t contracting

• latent, (3- 4 min)

3 periods of the muscle twitch

• 1) latent

• 2) contraction

• 3) relaxation

3 reasons a muscle responds

• 1) Changes in stimulus frequency

• 2) Variation in stimulus strength

• 3) Size principle of recruitment (larger motor units)

Single Twitch

• A single stimulus is delivered. The muscle contracts and relaxes

Wave summation

• unfused tetanus

• Another stimulus is applied before the muscle relaxes completely

High stimulation frequency

• Fused (complete) tetanus

• Fully contracted

• No relaxation between stimuli

Multiple motor unit summation AKA (recrution)

• delivering shocks of increasing voltage

Muscle tone

• muscles that are always slightly contracted

Isotonic contractions

• muscle length changes, moves a load

Concentric VS Eccentric contraction

• Concentric = length getting shorter

• Eccentric = length getting longer

Isometric contractions

• Does not change length but builds to peak muscle tension

3 ways to produce ATP

• 1) Direct phosphorylation

• 2) Burning Glucose

• 3) Aerobic respiration

Adding a phosphate to ADP and putting creatine (nutritional element) into muscles

• Direct phosphorylation (15 secs)

How does burning glucose work, and how long does it last?

• When you break the bonds, it releases energy

• (30s)

_________ pathway breaks glucose into __ parts

• Anerobic, 2

When you fully break down the glucose, it has the potential to give hours of energy is called………

• Aerobic respiration

How many ATP are in glucose

• 29-30

Know diagrams

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