Physiology

Question 1

Name some of the functions of the CSF

Answer 1

Shock absorbant that suspends the brain
Homestatic functions as PH effects pulmonary ventilation and cerebral blood flow
Circulation (medium for exchange of products)

Question 2

What do the ependymal cells line?

Answer 2

The choroid plexus in the ventricles of the brain

Question 3

Where are the foramen of magendie and luschka located? What is their function?

Answer 3

In the 4th ventricle they allow the CSF to flow out into the subarachnoid space.

Question 4

How does the CSF get from the subarachnoid space into the venous circulation?

Answer 4

Through arachnoid granulations then into the superior sagittal sinus to then get into the venous circulation

Question 5

Explain why carbonic anhydrase inhibitors are used to reduce ocular pressure

Answer 5

As they prevent the production of acqeous humour by blocking carbonic anhydrase that breaks up Hco3- meaning cannot generta H+ to be exchanged with na and cl- for the aqueous humour.

Question 6

Give some examples of carbonic anhydrase inhibitors and what they are used for

Answer 6

Dorzolamide and acetazolomide

Used to reduce ocular pressure in glaucoma

Question 7

What neurotransmitter is released from the photoreceptors in the eye

Answer 7

Glutamate

Question 8

The convergence for cones is lower than the convergences of rods. T/F

Answer 8

True- this means that rods are more likely to create an AP in the ganglion

Question 9

Where are langerhans cells found in the eye?

Answer 9

Corneo-scleral limbus

Question 10

What is immune privilige in the eye?

Answer 10

An area of the body that can tolerate antigens without making an inflammatory response- due to downregulatoin of the immune system

Question 11

The cornea and sclera are vascular. T/F

Answer 11

False- avascular

Question 12

Give an example of a condition mediated by type I hypersensitivity

Answer 12

Acute allergic conjucntivitis

Mast cella nd IGE mediated

Question 13

Give an example of a rection mediated by type II hypersensitivity

Answer 13

Occular cicatricial pemphigoid

Antibody mediated

Question 14

Give an example of a condition mediated by hypersensitivity reaction type III

Answer 14

Autoimmune corneal melting

Immune complex mediated

Question 15

Give an example of a condition mediated by type IV hypersensitivity

Answer 15

Corneal graft rejectoin

T cell mediated