week 4

Question 1

example of monosynaptic reflexes

Answer 1

knee jerk reflex

Question 2

example of polysynaptic reflex

Answer 2

withdrawal reflex

Question 3

what is a monosynaptic reflex

Answer 3

a simple reflex arc involving one synapse between a sensory and a motor neuron in the spinal cord

Question 4

In Grey matter in the spinal cord, what is in the dorsal horn

Answer 4

Sensory (afferent) input

Question 5

In Grey matter in the spinal cord, what is in the ventral horn

Answer 5

motor (efferent) output to skeletal muscle

Question 6

In Grey matter in the spinal cord, what is in the lateral horn

Answer 6

Autonomic (sympathetic) neurons

Question 7

In spinal cord tracts what is carried in the dorsal column

Answer 7

touch, vibration, proprioception

Question 8

in spinal cord tracts what is carried n the corticospinal tracts

Answer 8

voluntary control

Question 9

in spinal cord tracts what is carried in spinothalamic tracts

Answer 9

pain, temperature

Question 10

symptoms in anterior cord syndrome

Answer 10

motor loss, pain temp loss, proprioception spared

Question 11

symptoms in posterior cord syndrome

Answer 11

loss of proprioception and fine touch

Question 12

Visual pathway lesion in Optic nerve causes;

Answer 12

Mononuclear blindness

Question 13

Lesion in optic chiasm causes;

Answer 13

bitemporal hemianopia

Question 14

lesion in optic tract causes;

Answer 14

contralateral homonomous hemianopia

Question 15

lesion in meyers loop causes; (temporal)

Answer 15

contralateral superior quadrantanopia (pie in the sky)

Question 16

lesion in parietal radiation area causes;

Answer 16

contralateral inferior quadrantanopia

Question 17

lesion in occipital cortex causes;

Answer 17

homonymous hemianopia with maccular sparing

Question 18

What nerves are tested in the pupillary light reflex

Answer 18

CNII Optic
CNIII Occulomotor

Question 19

Describe the afferent limb of the pupillary light reflex pathway

Answer 19

Light enters one eye → activates retinal photoreceptors → signal sent via optic nerve

Travels to optic chiasm (partial decussation) → then to pretectal nucleus in the midbrain

Question 20

Describe the efferent pathway of the pupillary light reflex

Answer 20

Each pretectal nucleus sends bilateral projections to Edinger–Westphal nuclei (parasympathetic nucleus of CN III)

Parasympathetic fibers travel with CN III → ciliary ganglion → short ciliary nerves to the sphincter pupillae

Causes pupil constriction (miosis)

Question 21

what causes the consensual constriction of the pupil in the pupillary light reflex

Answer 21

Cross-communication via pretectal area → contralateral CN III

Question 22

Articulations of humeroulnar joint

Answer 22

Trochlea of humerus to trochlear notch of ulna

Question 23

humeroradial joint articulations

Answer 23

capitulum of humerus to head of radius

Question 24

proximal radioulnar joint articulations

Answer 24

head of radius to radial notch of ulna

Question 25

what are the ligaments of the elbow

Answer 25

Quadrate Annular Ulnar collateral Radial collateral

Question 26

muscles and nerve supply of elbow pronation

Answer 26

pronator teres, pronator quadratus Median Nerve

Question 27

muscles and nerve supply of elbow suppination

Answer 27

biceps brachii, supinator Musculocutaneous, radial nerve

Question 28

At what age does each bone get ossification centre in the elbow

Answer 28

Capitulum - 2 Radial head - 4 Internal epicondyle - 5 Trochlea - 9 Olecranon - 9 External epicondyle 11

Question 29

origin and insertion of coracobrachialis

Answer 29

coracoid process of scapula to medial mid shaft of humerus

Question 30

action of coracobrachialis

Answer 30

weak flexion and adduction at glenohumeral joint

Question 31

what pierces the coracobrachialis muscle

Answer 31

musculocutaneous nerve

Question 32

origin of biceps brachii

Answer 32

Short head; coracoid process of scapula long head; supraglenoid tubercle of scapula, the tendon runs through bicipital groove

Question 33

Insertion of biceps brachii

Answer 33

tuberosity of radius bicipital aponeurosis, blends into fascia of forearm

Question 34

action of biceps brachii

Answer 34

flexion at elbow and shoulder primary supinator when elbow is flexed

Question 35

origin of triceps brachii

Answer 35

long head; infraglenoid tubercle of scapula lateral head; posterior surface of humerus above radial groove medial head; posterior humerus below radial groove

Question 36

what happens to triceps in a mid shaft humerus fracture

Answer 36

Radial nerve can be damaged. However triceps is rarely paralysed due to high origin of branches.

Question 37

lateral border of cubital fossa

Answer 37

brachioradialis

Question 38

medial border of cubital fossa

Answer 38

pronator teres

Question 39

floor of cubital fossa

Answer 39

brachialis supinator