A&P Lab 1 (Chapter 8-9)

The Muscular system part 1 & 2

What are the 6 terms for ‘muscle size’?

1. Brevis

2. Longus

3. Vastus

4. Maximus

5. Minimus/minimi

6. minor

Brevis

short

• example: Fibularis Brevis (Fibularis has fibula in the name, so thats the location and brevis means short, so its a short muscle attached to the fibula bone/outer side of your leg)

longus

long

• example: adductor longus (a long muscle that draws a body part (arm, leg, finger, or thigh) toward the midline of the body)

Vastus

wide/large

• example: vastus lateralis

Maximus

largest

• gluteus maximas

Minimus/Minimi

smallest

example: gluteus minimus

Minor

small

example: pectoralis minor

What are the 8 muscle locations?

1. anterior

2. external

3. infra

4. intercostal

5. posterior

6. profundus

7. superficialis

8. supra

anterior

toward the front (ventral)

external

toward the outside

infra

below

intercostal

between the ribs

posterior

toward the bask (dorsal)

Profundus

deep (think of profoundly deep)

superficialis

nearer the surface (think of superficial)

supra

above

What are the 9 muscle actions?

1. abductor

2. adductor

3. depressor

4. erector

5. extensor

6. flexor

7. levator

8. pronator

9. supinator

abductor

pulls AWAY from midline

adductor

pulls toward the midline

depressor

pulls down

erector

holds erect/straight

extensor (think of increase)

increases angle between bones

flexor (think of flexing your muscle - it decreases the angle between two bones)

decreases angle between bones

levator (think of levitate - meaning raise)

raises a body part

pronator

turns palm posteriorly (dorsal)

supinator

turns palm anteriorly (ventral) (the correct anatomical position)

what are the 13 muscle body regions?

1. abdominis

2. brachii

3. capitis

4. carpi

5. cervicis

6. digitorum/digiti

7. femoris

8. gluteal

9. hallucis

10. oculi

11. oris

12. pectoralis

13. pollicis

abdominis

abdominal area

brachii

arm area

capitis

head area

carpi

wrist area

cervicis

neck area

digitorum/digiti

related to fingers or toes

femoris

femur or thigh

gluteal

butt

hallucis

great toe

oculi

eye area

oris

mouth area

pectoralis

chest area

pollicis

thumb

What are the 4 muscle fiber orientations?

1. oblique

2. orbicular

3. rectus

4. transversus

oblique

at an angle

orbicular

circular

rectus

straight

transversus

across/transverse

what are the 3 muscle heads?

1. biceps

2. triceps

3. quadriceps

biceps

two heads

triceps

three heads

quadriceps

four heads

The number of heads refers to the number of separate proximal attachments (origins) that converge into a single muscle belly and distal tendon.

What are the 5 muscle shapes?

1. deltoid

2. quadratus

3. rhomboid

4. serratus

5. trapezius

deltoid

triangular

quadratus

rectangle-shaped

rhomboid

rhomboid-shaped

serratus

serrated or jagged

trapezius

trapezoid-shaped

What are the 8 muscles that contribute to facial expressions?

1. epicranial aponeurosis

2. zygomaticus major/minor

3. levator labii superioris

4. risorius

5. mentalis

6. orbicularis oculi

7. orbicularis oris

8. buccinator

epicranial aponeurosis location and function?

large sheet of connective tissue that links the frontalis and occipitalis

• function: raises eyebrows and skin of forehead

what are the 3 muscles of the mouth? function?

1. zygomaticus major/minor

2. levator labii superioris

3. risorius

• function: move the lips and surrounding skin

mentalis location and function?

location: chin

• function: elevates and wrinkles the chin skin

  • primary function: express negative emotions (like doubt or displeasure)

orbicularis oculi location and function?

location: encircles the eye

function: moves the skin and soft tissues around the eyes - responsible for blinking and squinting

orbicularis oris function?

function: controls movements for eating, drinking and speaking

Buccinator location and function?

location: cheek muscle

function: compresses the cheeks against teeth and manipulates food during chewing

Muscles of the head and neck

Muscle of mastisfication & mouth movement

• Masseter and temporalis: primarily elevators for biting and chewing

Swallowing muscles:

• regional muscles groups coordinate chewing and swallowing; together they move food from oral cavity to esophagus

Head and neck movers

• Sternocleidomastoid rotates and flexes head

• trapezius extends the head and moves the neck through wide range of motion

What are the 3 muscles of the vertebral column? What are the muscles critical for?

1. erector spinae

• runs along the vetebral column and posterior (back) ribs; primary extensor of the spine

2. transversopinal group

• deep to erector spinae; fills grooves between transverse and spinous processes. includes semispinalis

3. quadratus lumborum

• large, deep muscle enabling vertebral column extension and lateral bending

Critical for both locomotion and posture

What are the 3 muscles of the trunk?

1. Diaphragm

• primary muscle of respiration

• function: contracts to increase thoracic volume and drive inhalation

2. External intercostals

• location: between ribs

• function: elevates the rib cage during inhalation (breathing in), increasing thoracic volume

3. Internal costals

• Location: deep to external intercostals

• function: depress the ribs during for forces exhalation (breathing out)

what are the 4 muscles of the trunk (in order)?

1. rectus abdominis

• enclosed in rectus sheath

• function: flexes the trunk

2. external & internal obliques

• diagonal fibers

• function: rotates and laterally flexes the trunk

3. tranversus abdominis

• deepest layer

• compresses the abdomen and stabilizes the core

4. Linea Alba

• connective tissue at the abdominal midline, separating left and right rectus muscles

What are the 5 muscles of the shoulder and arm (from shoulder to arm, in order)?

1. scapular movers

2. humeral movers

3. elbow movers

4. anterior forearm movers

5. posterior forearm movers

what are the 6 scapular movers?

Serratus anterior, pectoralis minor, trapezius, levator scapulae, rhomboid major & minor

what are the 8 humeral movers?

Pectoralis major, latissimus dorsi, teres major, coracobrachialis, and rotator cuff: teres minor, supraspinatus, infraspinatus, subscapularis

what are the 4 elbow movers?

Biceps brachii, brachialis, brachioradialis (flex); Triceps brachii (extend)

what are the 3 anterior (ventral/front) forearm movers?

Wrist flexors (flexor carpi radialis, flexor carpi ulnaris) and finger/thumb flexors (flexor digitorum superficialis & profundus) in the deep layer

what are the 3 posterior forearm movers?

Wrist extensors (extensor carpi radialis longus, extensor carpi ulnaris) and finger/thumb extensors (extensor digitorum, extensor pollicis longus) in the deep layer.

What muscles move the thigh and knee?

Anterior: Flex Thigh

• Iliopsoas and sartorius flex the thigh at the hip.

Quadriceps: Extend Knee

• Rectus femoris, vastus lateralis, vastus medialis, vastus intermedius extend the leg at the knee.

Medial: Adduct Thigh

• Adductor magnus, adductor longus, pectineus, and gracilis adduct the thigh and assist hip/knee flexion.

Gluteal : Extend & Rotate

• Gluteus maximus, medius, and minimus extend, abduct, and rotate the thigh.

Hamstrings: Flex Knee

• Biceps femoris, semitendinosus, semimembranosus flex the leg at the knee.

Deep Posterior: Rotate

• Piriformis and quadratus femoris laterally rotate the thigh.

What muscles move the ankle and foot?

Tibialis Anterior

• Located on the anterior leg.

• Function: dorsiflexion of the foot at the ankle (lifts the foot upward toward the shin).

Gastrocnemius & Soleus

• Powerful calf muscles that plantar flex the foot (pointing the foot downward).

• Essential for walking, running, and jumping.

Plantaris

• A small, slender muscle that assists the gastrocnemius in plantar flexion of the foot at the ankle.