Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Ophthalmology Week 1 > Physiology > Flashcards

Physiology Flashcards

1
Q

what is CSF mostly composed of?

A

water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what produces CSF?

A

secretory epithelium of the choroid plexus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

how many times a day is CSF replaced?

A

3-4 times

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what does the CSF supply?

A

water, amino acids and ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what does CSF remove?

A

metabolites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are the 3 major functions of CSF?

A

mechanical protection, homeostatic function, circulation function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how does CSF provide mechanical protection?

A

shock-absorbing medium that protects brain tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the homeostatic function of CSF?

A

pH of CSF affects pulmonary ventilation and cerebral blood flow. transports hormones.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

embrylogically, at 3 weeks what does the developing nervous system consist of?

A

a tube - neural canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what does the cavity of the neural canal give rise to in the adult brain?

A

the brains ventricles and the spinal cord’s central canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what does the choroid plexus develop from?

A

cells in walls of the ventricles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what forms the choroid fissure?

A

developing arteries invaginate the roof of the ventricle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what does the secretion of fluid by the choroid plexus depend on?

A

on the active sodium transport across the cells into the CSF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the difference in ion, glucose and protein concentrations from blood plasma and CSF?

A

CSF has lower potassium, glucose and much lower protein than blood plasma, has higher concentrations of sodium and chloride than blood plasma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

is the production of CSF in the choroid plexuses directly dependent on the arterial BP?

A

no it is an active secretory process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what connects the lateral ventricle to the third ventricle?

A

intraventricular foramina (of Monroe)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what connects the 3rd ventricle to the 4th?

A

cerebral aqueduct (of Sylvius)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what connects the 4th ventricle to subarachnoid space?

A

foramen of Magendie: Median aperture

19
Q

what does the lateral aperture of Foramina of Luschka connect?

A

4th ventricle to subarachnoid space

20
Q

where is the site of the blood-brain-barrier (BBB)?

A

endothelial cells in brain capillaries

21
Q

what does the BBB consist of?

A

of the capillary endothelium, its basal membrane and perivascular astrocyes

22
Q

what parts of the brain do not have the BBB?

A

circumventricular organs or pineal gland

23
Q

what does the BBB protect the brain from?

A

many common bacterial infections and toxins, drug delivery

24
Q

where is a colloid cyst of the brain often found?

A

at the interventricular foramen

25
Q

what does a ependymonas arrise from?

A

arrising from ependymal cells lining the ventricles

26
Q

what kind of hematoma is it if it is arterial blood between the skull and dura?

A

epidural hematoma

27
Q

what kind of blood and where is the blood in a subdural hematoma?

A

venous blood between the dura and the arachnoid

28
Q

what is hydrocephalus?

A

accumulation of CSF in the ventricular system or around the brain

29
Q

what can cause hydrophalus?

A

either obstruction of over-production of CSF

30
Q

what are the 2 layers of epithelium in the ciliary body and posterior surface of iris?

A

-a forward continuation of the pigmented epithelium of the retina overlain by an inner nonpigmented epithelial layer

31
Q

what are the 4 main regions of a photoreceptor?

A
  • outer segement
  • inner segement
  • cell body
  • synaptic terminal
32
Q

what are the types of photoreceptors?

A

rods and cones

33
Q

what do photoreceptors do?

A

converts electromagnetic radiation to neural signals

34
Q

what happens the Vm of photoreceptors on light exposure?

A

it hyperpolarizes

35
Q

what is a positive Vm of photoreceptors due to?

A

the ‘dark current’

36
Q

what type of channel in the photoreceptors opens in the dark and closes in the light?

A

cGMP-gated sodium channel

37
Q

this change in sodium with light in the photoreceptors enables what?

A

the brain to perceive objects in the visual field

38
Q

what are the visual pigment molecules called?

A

Rhodopsin

39
Q

where are Rhodopsin present?

A

in membrane folds called discs in the outer segment

40
Q

what does light convert 11-cis-Retinal to?

A

to all-trans-Retinal

41
Q

when is the dark current channel open?

A

in the dark

42
Q

what is visual acuity?

A

ability to distinguish 2 nearby points

43
Q

what is visual acuity largely determined by?

A

photoreceptor spacing and refractive power

44
Q

what photoreceptors are used more in daylight?

A

cones

Ophthalmology Week 1 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions