Anatomy Lab Quiz #3

Bones/Muscles of Upper Extremity, CNS

what bones make up the pectoral girdle?

clavicles & scapula

what is the purpose of the pectoral skeleton?

attaches upper limbs to axial skeleton; attachment site for muscles that move upper limbs

what do the clavicles articulate with?

sternum (medially) & scapula/acromion (laterally)

function of the clavicles

anchors muscles, act as brace to hold scapula & arms out laterally

scapula

between ribs 2 & 7, flat & triangular, 3 borders & 3 angles

how do you tell the anterior from the posterior on the scapula?

scapular spine is posterior, anterior surface is always smooth

how do you tell the medial from the lateral on the scapula?

medial is long, smooth border; acromion is lateral

acromion

continues w/ scapular spine posteriorly

glenoid cavity/fossa

“socket” part of the ball and socket joint, articulates with the head of the humerus

coracoid process

hooked, superior lateral side of scapula

suprascapular notch

indentation at top of scapula

supraspinous fossa

scooped out area above scapular spine

infraspinous fossa

scooped out area below scapular spine

how do you tell anterior from posterior on the humerus?

bowtie at distal end is anterior

how do you tell medial from lateral on the humerus?

the head of the humerus always points medially

greater tubercle of humerus

bigger bump

intertubercular sulcus

groove between the bumps

head of humerus

articular surface, “ball” of ball and socket joint

deltoid tuberosity

bump made by deltoid muscle, midway down bone

coronoid fossa

scooped out area that bone fits into

capitulum

articulates w/ radial head, for rotation

olecranon fossa

scooped out area the olecranon process (ulna) fits into

medial epicondyle

bone that’s on top of the condyle

trochlea

“pulley” articulation w/ the ulna (flexion & extension)

how do you tell medial from lateral at the elbow joint?

the ulna is always medial (has the styloid process if anterior & projects up if posterior)

coronoid process

beak-like projection of ulna

radial tuberosity

bump on radius, on medial side of radius

interosseous membrane

membrane between bones

styloid process

pen-like protrusion

ball-and-socket joint of the shoulder

• made up of glenoid fossa of scapula & head of humerus

• multiaxial

• flexion/extension, abduction/adduction, rotation

elbow joint

• made of the trochlea of humerus & trochlear notch of the ulna

• uniaxial

• flexion/extension

proximal interphalangeal joint (PIP)

hinge joint, uniaxial (flexion/extension)

metacarpophalangeal joint (MCP)

condyloid joint, biaxial (flexion/extension & abduction/adduction)

distal interphalangeal joint (DIP)

hinge joint, uniaxial (flexion/extension)

interphalangeal joint (IP)

hinge joint, uniaxial (flexion/extension)

carpometacarpal joint

saddle joint, specific to thumb

what muscles produce flexion?

ones that cross the anterior surface of a joint

what muscles produce flexion?

ones that cross the posterior surface of a joint

what muscles produce abduction?

ones that cross the lateral surface of a joint

what muscles produce adduction?

ones that cross the medial surface of a joint

subclavius

“under the clavicle”, stabilizes scapula, attach on scapula

pectoralis minor

pulls scapula forward (anterior) & downward (inferior), attach on scapula

serratus anterior

used in pushing/punching & horizontal scapular movements, attaches to scapula

trapezius

trapezoid-shaped, elevates & rotates scapula, attach on scapula

levator scapula

elevates & adducts scapula, attach on scapula

rhomboid major/minor

rotate scapula, attach on scapula

deltoid

prime mover of shoulder for abduction, attach on humerus

pectoralis major

prime mover for shoulder flexion, adduction, attach on humerus

latissimus dorsi

puller upper extremity into extension, attaches on humerus

supraspinatus (green)

above scapular spine, rotator cuff muscle, attaches on humerus

infraspinatus

below scapular spine, rotator cuff muscle, attaches on humerus

teres minor

rotator cuff muscle, attaches on humerus

subscapularis

under scapula, rotator cuff muscle, attaches on humerus

biceps brachii

prime mover in elbow flexion, attach on the forearm

brachioradialis

helps w/ forearm/elbow flexion, attach on the forearm

brachialis

deep to biceps brachii, forearm/elbow flexion, attach on the forearm

triceps brachii

prime mover for elbow extension, attach on the forearm

anconeus

tiny, helps stabilize elbow during extension, attach on the forearm

pronator quadratus

prime mover in pronation, attach on the forearm

pronator teres

adds to pronation, attach on the forearm

supinator

supination/turns palm up, attach on the forearm

flexor carpi radialis

causes wrist flexion, lateral deviation, on thumb-side

flexor carpi ulnaris

wrist flexion, medial deviation, on pinky-side

flexor digitorum superficialis

flexion of wrist and digits 2-5

palmaris longus

weak wrist flexion

flexor pollicis longus

causes thumb flexion

flexor digitorum profundus

causes distal finger flexion

extensor carpi radialis longus/brevis

causes wrist extension, thumb-side

extensor digitorum

prime mover of finger extension

extensor indices

extension of index finger

extensor carpi ulnaris

causes wrist extension

extensor pollicis longus/brevis

causes thumb extension

abductor pollicis longus

causes thumb abduction

hypothenar eminence

includes muscles that flex, abduct, and oppose the 5th digit (flexor digit minimi brevis, abductor digiti minimi, opponens digiti minima)

midpalmar muscles

includes deep muscles that flex, abduct, adduct the fingers (lumbricals, interossei)

thenar eminence

includes muscles that flex, abduct, adduct, and oppose the thumb (adductor pollicis, flexor pollicis brevis, abductor pollicis brevis, opponens pollicis)

central sulcus

separates the frontal lobe anteriorly from the parietal lobe posteriorly

precentral gyrus

houses the primary motor cortex and controls voluntary movement throughout the body

postcentral gyrus

houses the primary somatosensory cortex

corpus callosum

thick, C-shaped bundle of nerve fibers, acts as a neural bridge that connects the left and right cerebral hemispheres

fornix

C-shaped, arching bundle of nerve fibers (white matter) in the brain that acts as the primary output tract of the hippocampus

thalamus

mass of gray matter located deep in the center of the brain above the brainstem, acting as the primary information relay station and sensory gateway to the cerebral cortex

hypothalamus

just below the thalamus and above the brainstem. It acts as the body's main control center, linking the nervous system to the endocrine system to keep internal bodily functions balanced

optic chiasm

at the base of the brain where the optic nerves from each eye meet and partially cross over

pituitary gland

located at the base of the brain, just beneath the hypothalamus; controls other hormone-producing glands in the body and regulates essential functions like growth, metabolism, reproduction, and water balance

pons

acts as a major neural bridge connecting the higher brain and cerebellum to the spinal cord and medulla oblongata

medulla oblongata

lowest part of the brainstem, connecting the brain to the spinal cord; regulates vital involuntary processes, including heart rate, blood pressure, and breathing; manages protective

cerebellum

motor control & coordination, balance & posture, motor learning, cognitive & sensory roles

arbor vitae

branched, tree-like network of white matter located inside the cerebellum

mammillary body

located at the posteroinferior aspect of the hypothalamus within the diencephalon of the brain; essential for the processing, consolidation, and recall of episodic and spatial information

pineal gland

in the epithalamus region of the brain, main job is to synthesize and secrete melatonin

choroid plexus of the 4th ventricle

produces cerebrospinal fluid

what type of material composes the gray matter of the CNS?

cell bodies & unmyelinated axons

what type of material composes the white matter of the CNS?

myelinated axons

dorsal root ganglion

located on the dorsal (back) root of each spinal nerve just outside the spinal cord; collects & transmits sensory information (fine touch, pressure, vibration, temperature, & pain) from the body's periphery to the central nervous system

3 meningial layers that cover the brain & spinal cord

1. dura mater (outermost, thickest)

2. arachnoid mater (web-like)

3. pia mater (innermost, thin & clear)

pyramids of medulla

ridges on the ventral surface of the medulla, composed of neurons leaving the CNS

lateral ventricles (in green)

pair of large, C-shaped fluid-filled cavities located within each cerebral hemisphere of the brain

3rd ventricle (in red)

narrow, slit-like cavity located along the midline of the brain's diencephalon, positioned between the left and right thalami

4th ventricle (in green)

located within the brainstem, dorsal to the pons and upper medulla oblongata and ventral to the cerebellum