Lab Exam 3

Question 1

List muscles of head and functions (9)

Answer 1

1. occipitofrontalis (frontal belly and occipital belly):
2. orbicularis oculi:
3. temporalis:
4. masseter:
5. Buccinator:
6. Orbicularis Oris:
7. Zygomaticus major:
8. zygomaticus minor:
9. Risorius:

Question 2

Answer 2

Occipitofrontalis: Frontal belly, occipital belly seperated by epicranial aponeurosis

frontal belly: Elevates the eyebrows from a neutral position, creating horizontal wrinkles across the forehead.
occipital belly: Pulls the scalp backward from a neutral position, which smooths the forehead and can lower the eyebrows slightly if the frontal belly is relaxed.

Question 3

Answer 3

orbicularis oculi

Constricts the eyelids, bringing them together from an open or neutral position. This action includes both gentle closing, such as in blinking, and forceful closing, as in squinting

Question 4

Answer 4

temporalis

Elevates the mandible from a resting position, closing the jaw. It also retracts the mandible, pulling the lower jaw backward from a protruded position. This action is essential for biting and chewing.

Question 5

Answer 5

Masseter

Elevates the mandible

from a resting position, closes the jaw.

Question 6

Answer 6

Buccinator

Compresses the cheek against the teeth, assisting in actions like blowing, sucking, and keeping food between the teeth during chewing. This action pulls the cheek inward from a neutral position

Question 7

Answer 7

Orbicularis Oris

Closes and purses lips.

Question 8

Answer 8

Zygomaticus Major

Elevates corner of mouth

Question 9

Answer 9

Risorius

Draws corner of mouth laterally (smiling / sonrisa)

Question 10

Answer 10

Sternocleidomastoid

Unilateral action laterally flexes (brings head to shoulders) or rotates the neck, bilateral action flexes the neck forward (nodding)

Question 11

Answer 11

Anterior, middle and posterior scalenes

Elevate the first and second ribs during inspiration, lateral flexion of the neck (head to shoulder).

Question 12

List Muscles of the neck / back and functions (10)

Answer 12

1. sternocleidomastoid:
2. scalenes anterior / middle / posterior:
3. Levator Scapulae:
4. Trapezius:
5. Rhomboid Major:
6. Rhomboid Minor:
7. Serratus Anterior:
8. Erector Spinae longissimus:
9. erector spinae iliocostalis:
10. erector spinae spinalis:
11. Latissimus Dorsi:

Question 13

Answer 13

Levator Scapulae

Elevates the scapula (raises the shoulder blade toward the ear) from a neutral position.

Question 14

Answer 14

Trapezius

Elevates / depresses / retracts the shoulder

Question 15

Answer 15

latissimus dorsi

• Humerus / shoulder adduction: The movement of bringing the humerus closer to the body’s midline.

adducts the humerus from a more overhead or extended position, pulling the arm down toward the body from above, like when pulling something down from above your head.

Question 16

Answer 16

Rhomboid Major

Retracts the shoulder (scapula adduction) (pulls the shoulder blades toward the spine) from a protracted position.

Question 17

Answer 17

Rhomboid Minor

Retracts the shoulder (scapula adduction)

pulls the shoulder blades toward the spine

Question 18

Answer 18

Serratus anterior

Protracts the shoulder (scapulae abduction) (pulls the shoulder blade forward and around the ribcage, as in pushing or punching movements).

Question 19

Answer 19

erector spinae spinalis

Extends the vertebral column (pulls the spine backward from a flexed position), particularly focusing on the thoracic region. It helps maintain an upright posture.

erector spinae longissimus
directly lateral to spinalis

Extends the vertebral column (pulls the spine backward) and assists in lateral flexion (bends the spine to the side). It also plays a role in the rotation of the head and neck.

erector spinae iliocostalis

ilio costalis branches

Extends the vertebral column (pulls the spine backward) and assists in lateral flexion (bends the spine to the side), particularly affecting the thoracic and lumbar regions. It also helps stabilize the spine during movement.

Question 20

Answer 20

diaphragms

Contraction increases volume of thoracic cavity

Question 21

Answer 21

External intercostals

elevates rib cage during inspiration.

Question 22

Answer 22

Internal intercostals

depresses rib cage during expiration

Question 23

Answer 23

pectoralis major

horizontally Adducts the humerus

Primarily adducts the humerus from a position where the arm is raised or out to the side (abducted). It pulls the arm toward the body in a more horizontal plane, as in bringing the arms together in front of the chest.

Question 24

List Muscles of the Anterior Trunk

Answer 24

1. Diaphragm:
2. External intercostals:
3. Internal intercostals:
4. Pectoralis major:
5. Pectoralis Minor:
6. Rectus Abdominis:
7. External Oblique:
8. transverse abdominis:

Question 25

Answer 25

**pectoralis minor** **protracts and depresses shoulder** *Protracts the scapula (pulls the shoulder blade forward and around the ribcage) and depresses the scapula (lowers the shoulder blade).*

Question 26

Answer 26

**Rectus abdominis** **Flexes the vertebral column** *brings the torso forward from a neutral or extended position, as in performing a sit-up*

Question 27

Answer 27

**external abdominal oblique** **Laterally flexes the vertebral column** *lateral flexion, flexes torso to one side*

Question 28

Answer 28

**internal abdominal oblique** *laterally flexes the vertebral column / flexes vertebral column*

Question 29

Answer 29

**transverse abdominis** **Compresses abdominal wall** *draws the abdomen inward*

Question 30

Answer 30

**Deltoid** **Abducts the humerus** (raises the arm away from the body) from a neutral position, particularly from 15 to 90 degrees.

Question 31

Answer 31

**Supraspinatus** **abducts humerus** *Initiates abduction of the arm (raises the arm away from the body), particularly the first 15 degrees of movement before the deltoid muscle takes over.*

Question 32

Answer 32

**Infraspinatus** **Lateral rotation of humerus** from anatomical position lateral rotation of the humerus by the infraspinatus muscle rotates the arm so that the palm turns to face outward, away from the body

Question 33

Answer 33

**Teres Major** **medial rotation of humerus** *medial rotation of humerus: from anatomical position medial rotation causes the palm to turn toward the body / backwards*

Question 34

Answer 34

**Teres Minor** **Laterally rotates the humerus** *works with infraspinatus to laterally rotate humerus, from anatomical position turns palm outward*

Question 35

Answer 35

**Subscapularis** **medial rotation of humerus** *The subscapularis and teres major work together to medially rotate the humerus, turning the upper arm bone inward toward the body’s midline, which causes the palm to turn inward or backward from the anatomical position.*

Question 36

Answer 36

**Biceps Brachii** **Flexes the elbow** *brings the forearm toward the upper shoulder*

Question 37

Answer 37

**Coracobrachialis** *Deep to biceps, attaches to the coracoid process of the scapula deep to short head of bicep attachment* **shoulder flexion** *from anatomical position raise arm infront of you (not out to the side)* shoulder / humerus abduction = raising arm to the side shoulder / humerus flexion = raising arm in front of you

Question 38

List Muscles of acromial and brachial regions

Answer 38

1. **Deltoid** 2. **Supraspinatus** 3. **Infraspinatus** 4. **Teres Minor** 5. **Teres Major** 6. **Subscapularis** 7. **Brachialis** 8. **Biceps Brachii** 9. **Coracobrachialis** 10. **Triceps Brachii**

Question 39

Answer 39

**triceps brachii** **Extends the elbow** *straightens arm from a flexed position*

Question 40

Answer 40

**Brachialis** *deep to bicep brachii* *elbow flexion*

Question 41

List Muscle of the antebrachial region

Answer 41

1. **pronator teres** 2. **flexor carpi radialis** 3. **palmaris longus** 4. **Flexor Carpi Ulnaris** 5. **Flexor Digitorum Superficialis** 6. **Flexor Pollicis longus** 7. **Brachioradialis** 8. **Extensor carpi radialis longus** 9. **Extensor carpi radialis brevis** 10. **Extensor digitorum** 11. **Extensor carpi ulnaris** 13. **supinator**

Question 42

Answer 42

**pronator teres** *lateral to flexor carpi radialis and medial to brachioradialis. Goes under brachioradialis* **pronation** Rotates the forearm inward, turning the palm downward from a supinated or neutral position.

Question 43

Answer 43

**Flexor carpi radialis** *medial to pronator teres. Attaches at thumb side of carpals.* *moving medially, pronator teres, flexor carpi radialis, palmaris longus, flexor carpi ulnaris* **flexes the wrists** *from anatomical position brings hand towards forarm*

Question 44

Answer 44

**Palmaris longus** *medial to flexor carpi radialus, lateral to flexor carpi ulnaris* **weak flexion of wrist**

Question 45

Answer 45

**Flexor digitorum superficialis** *deep to flexor carpi radialis and palmaris longus* *Flexes fingers and wrists*

Question 46

Answer 46

**flexor carpi ulnaris** *medial to palmaris longus, wraps to posterior of arm.* **Flexes the wrist** bends the wrist forward

Question 47

Answer 47

**flexor pollicis longus** *deep and lateral to flexor digitorum superficialis* **Flexes the thumb**

Question 48

Answer 48

**Brachioradialis** *lateral to flexor carpi radialis. The large lateral side of the V formed with pronator teres* **Flexes the elbow** brings the forearm toward the upper arm

Question 49

Answer 49

**Extensor Carpi Radialis Longus** *directly lateral and a bit around the arm to the brachioradialis. Attaches at first metacarpal* **Extends the wrist** *straightens the wrist from a flexed position*

Question 50

Answer 50

**Extensor Carpi Radialis brevis** *posteriorly adjacent to extensor carpi radialis longus* **Extends the wrist**

Question 51

Answer 51

**extensor digitorum** *between extensor carpi radialis breves and extensor carpi ulnaris* **Extends the fingers** *straightens the fingers from a flexed position*

Question 52

Answer 52

**extensor carpi ulnaris** *medial to extensor digitorum, connects at pinky side, lateral to flexor carpi ulnaris* **Extends the wrist** straightens the wrist from a flexed position *makes v with flexor carpi ularis (medial)*

Question 53

Answer 53

**supinator** *deep to brachialradialis* **Supinates the forearm** rotates the forearm outward, turning the palm upward from a pronated or neutral position.

Question 54

List muscles of hip and thigh

Answer 54

1. **Gluteus Maximus** 2. **Gluteus Medius** 3. **Piriformis** 4. **Psoas Major** 5. **Iliacus** 6. **Hamstrings** - Biceps femoris, Semitendinosus, Semimembranosus 7. **Sartorius** 8. **Quadriceps Femoris** - Rectus femoris, vastus lateralis, vastus medialis, vastus intermedius 9. **Adductor longus** 10. **Adductor magnus** 11. **Gracilis** 12. **Tensor Fasciae Latae**

Question 55

Answer 55

**Gluteus Maximus** **hip extensions / hip abduction** moves the leg backward from a flexed position

Question 56

Answer 56

**Gluteus Medius** **Abducts the hip** moves the leg away from the midline of the body

Question 57

Answer 57

**Piriformis** **lateral rotation of femur** rotates the thigh outward / from the anatomical position, lateral rotation causes the foot to point outward, away from the midline. *deep to gluteus maximus*

Question 58

Answer 58

**Psoas Major** *directly medial to iliacus* **Flexes the thigh / hip** brings the thigh upward toward the torso

Question 59

Answer 59

**Iliacus** *directly lateral to psoas major* **Flexes the thigh / hip** brings the thigh upward toward the torso

Question 60

Answer 60

**Hamstrings** **Long Head of Biceps Femoris** *most lateral* **Semitendinosus** *middle* **Semimembranosus** *most medial* *Flexes the knee* bends the leg at the knee joint bringing the foot towards the ass

Question 61

Answer 61

**Sartorius** **Flexes the thigh / hip** brings the thigh upward toward the torso

Question 62

Answer 62

**Quadriceps Femoris** **Rectus femoris** large central muscle **vastus lateralis** lateral to rectus femoris **vastus medialis** medial to rectus femoris **vastus intermedius** deep to rectus femoris *knee extension - from flexed position, straightens leg*

Question 63

Answer 63

**Adductor longus** **Adducts the thigh / hip** brings the thigh inward toward the body's midline *Same layer as gracilis (#15), on model adductor magnus is lateral and deep to gricilis*

Question 64

Answer 64

**Adductor magnus** **Adducts the thigh** *It is deep to Gracilis (15), partially covered by adductor longus which is the same layer as gracilis*

Question 65

Answer 65

**Gracilis** **Hip adduction** *Gracilis #15, Adductor magnus #14, Adductor longus medial.*

Question 66

Answer 66

**Tensor Fasciae Latae** **Hip abduction** *It is directly lateral and superior to rectus femoris*

Question 67

List muscles of lower leg

Answer 67

1. **Gastrocnemius** 2. **Soleus** 3. **Popliteus** 4. **tibialis posterior** 5. **Flexor digitorum longus** 6. **Flexor hallucis longus** 7. **Tibialis anterior** 8. **Extensor digitorum longus** 9. **Fibularis (peroneus) longus** 10. **Fibularis (peroneus) brevis**

Question 68

Answer 68

**Gastrocnemius** **Plantar flexes the foot** points the toes downward

Question 69

Answer 69

**Soleus** **Plantar flexes the foot** points the toes downward, pushing the foot away from the body *Deep to gastrocnemius*

Question 70

Answer 70

**Popliteus** **Knee flexion** *posterior, lateral deep to lateral head of gastrocnemius* *26, 28 is tibialis posterior*

Question 71

Answer 71

**tibialis posterior** *medial to flexor hallucis longus, lateral to flexor digitorum longus* **Inverts the foot** turns the sole inward *26 is popliteus*

Question 72

Answer 72

**Flexor digitorum longus** **Toe flexion** curls the toes downward *26 popliteus, 29 flexor hallicus longus, 28 tibialis posterior muscle* *medial, primarily posterior but can see inferior section from anterior view under soleus*

Question 73

Answer 73

**Tibialis anterior** *superficial / anterior to tibialis posterior* **Dorsiflexes the foot** lifts the foot upward *The picker upper*

Question 74

Answer 74

**Extensor digitorum longus** **Extends the toes** - lifts the toes upward **dorsiflexes the foot** - lifts the foot upward

Question 75

Answer 75

**Fibularis (peroneus) longus** *lateral to extensor digitorum longus* **Everts the foot** turns the sole outward

Question 76

Answer 76

**Fibularis (peroneus) brevis** *deep to fibularis longus, lateral (pinky side / fibulae) of leg* **Everts the foot** turns the sole outward

Question 77

Answer 77

**flexor hallucis longus** **Flexes the great toe (hallux)**

Question 78

Answer 78

**Axillary Nerve** *68* Plexus: Brachial Plexus Function: Innervates the deltoid and teres minor muscles, enabling shoulder abduction and rotation, and provides sensory innervation to the skin over the deltoid region.

Question 79

Answer 79

**Radial Nerve** *80* Plexus: Brachial Plexus Function: Innervates the muscles of the posterior arm and forearm, including the triceps brachii and extensor muscles, enabling extension of the elbow, wrist, and fingers, and provides sensory innervation to the posterior arm, forearm, and hand.

Question 80

Answer 80

**Musculocutaneous** *70* Plexus: Brachial Plexus Function: Innervates the muscles of the anterior arm, including the biceps brachii, brachialis, and coracobrachialis, enabling flexion of the elbow, and provides sensory innervation to the lateral forearm.

Question 81

Answer 81

**Median** *71* Plexus: Brachial Plexus Function: Innervates most of the anterior forearm muscles and some hand muscles, enabling flexion of the wrist and fingers, and provides sensory innervation to the lateral palm and the first three and a half fingers.

Question 82

Answer 82

**ulnar** Plexus: Brachial Plexus Function: Innervates the intrinsic muscles of the hand and some forearm muscles, enabling fine motor control of the hand and fingers, and provides sensory innervation to the medial side of the hand, including the little finger and half of the ring finger.

Question 83

Answer 83

**Femoral** Plexus: Lumbar Plexus Function: Innervates the anterior thigh muscles, including the quadriceps, enabling extension of the knee, and provides sensory innervation to the anterior thigh and the medial lower leg via the saphenous nerve

Question 84

Answer 84

**Sacral Plexus**

Question 85

Number 67

Answer 85

**Brachial Plexus**

Question 86

61

Answer 86

**Obturator** Plexus: Lumbar Plexus Function: Innervates the medial thigh muscles, including the adductors, enabling adduction of the thigh, and provides sensory innervation to the skin of the medial thigh.

Question 87

Answer 87

**sciatic** Plexus: Sacral Plexus Function: Innervates the posterior thigh muscles, including the hamstrings, enabling thigh extension and knee flexion, and it branches into the tibial and common fibular nerves, which innervate the lower leg and foot.

Question 88

#64

Answer 88

**Tibial** Plexus: Sacral Plexus (as a branch of the Sciatic Nerve) Function: Innervates the muscles of the posterior compartment of the lower leg, including the gastrocnemius and soleus, enabling plantar flexion of the foot and flexion of the toes, and provides sensory innervation to the sole of the foot.

Question 89

Answer 89

**Common Fibular** Plexus: Sacral Plexus (as a branch of the Sciatic Nerve) Function: Innervates the muscles of the anterior and lateral compartments of the lower leg, enabling dorsiflexion of the foot and extension of the toes, and provides sensory innervation to the upper lateral leg and dorsum of the foot.

Question 90

What nerves are carried in the dorsal root, the ventral root, what is the dorsal root ganglion?

Answer 90

The dorsal root contains sensory neurons. The ventral root contains motor neurons. The dorsal root ganglion is a cluster of sensory neuron cell bodies located in the dorsal root of a spinal nerve.

Question 91

What do the ascending and descending tracts convey

Answer 91

The ascending tracts of the white columns convey sensory information to the brain. The descending tracts of the white columns convey motor commands from the brain to the spinal cord.