BB physiology

Question 1

Control of drinking

Answer 1

Osmoreceptors in subfornical organ of 3rd ventricle

Project to medial pre optic nucleus of hypothalamus (thirst) and paraventricular and supraoptic nucleus (ADH release)

Question 2

Control of eating

Answer 2

Lateral hypothalamus = hunger centre

Medial hypothalamus = satiety centre

Question 3

Ghrelin

Answer 3

Produced by cells lining the stomach

Project to periventricular nucleus to inhibit satiety

Question 4

Leptin

Answer 4

Produced by adipose tissue
Long term monitor of energy stores
Acts on hypothalamus

Question 5

CCK

Answer 5

Released when chyme received in duodenum

Acts on arcuate nucleus to induce satiety

Question 6

Broadmann area 44

Answer 6

Broca’s

Question 7

Broadmann area 22

Answer 7

Wernicke’s

Question 8

Broadmann area 4

Answer 8

Primary motor cortex

Question 9

Broadmann area 1,2,3

Answer 9

Primary somatosensory cortex

Question 10

Broadmann area 17

Answer 10

Primary visual cortex

Question 11

Broadmann area 41 and 42

Answer 11

Primary visual cortex

Question 12

Photoreceptor actvity

Answer 12

Dark = constant inward leak of sodium to keep the cell depolarised and tonically releasing sodium

Question 13

Eye blood supply

Answer 13

Ophthalmic artery

Choroid network of capillaries

Question 14

Accommodation reflex

Answer 14

Pupillary constriction - CN III PS
Thickening of lens - CN III PS
Convergence - CN III

Question 15

Nystagmus

Answer 15

Cold = flick towards non-irrigated ear

Warm - flick towards irrigated ear

Question 16

Glaucoma treatments

Answer 16

Prostaglandin analogs
Beta-adrenergic receptor antagonists 
Alpha 2 adrenergic agonists 
Parasympathomimetic agonists
Anticholinesterases 
Carbonic anhydrase inhibitors

Question 17

Ear ossicles

Answer 17

Malleus –> incus –> stapes

Question 18

Membrane of organ of Corti

Answer 18

3 rows of outer hair cells

1 row of inner hair cells

Question 19

Cochlear frequency preference

Answer 19

Thin and wide at apex - best for low frequency

Thick and narrow at base - best for high frequency

Question 20

Impedance matching

Answer 20

Relative sizes of ossicles

Tympanic membrane larger than oval window

Question 21

Attenuation reflex

Answer 21

Slow
Stapedius muscle
Prevents damage to ear structures

Question 22

Startle reflex

Answer 22

Facial nerve and reticular formation
Serves to protect back of neck and eyes
Fast

Question 23

Cochlear nucleus

Answer 23

Ventral = fast and precise --> superior olivary nucleus 
Dorsal = complex --> lateral lemniscus

Question 24

Sound localisation

Answer 24

Interaural time differences more useful at low frequencies

Intramural level differences more useful at high frequencies