lab 11

Question 1

what are the general senses?

Answer 1

• the somatic senses (touch, pressure, pain, temperature, and proprioception)
• visceral senses which provide information about our internal organs
• special senses: vision, hearing, equilibrium, taste and smell

Question 2

what does adipose tissue function as on the eye?

Answer 2

adipose tissue functions as padding and insulation within the orbit to protect the eye

Question 3

function of sclera on the eye

Answer 3

sclera consists of dense fibrous connective tissue that forms the tough external coat
-functions to protect and shape the eyeball and provide a study anchoring site for extrinsic eye muscles

Question 4

function of the cornea on eye

Answer 4

allows light to enter the eye and helps bend light rays so they are focused on the photoreceptors in the retina

Question 5

what is the fluid found behind the cornea

Answer 5

aqueous humor- it maintains intraocular pressure/ inflates the globe of the eye

Question 6

what is the iris

Answer 6

the iris is the circular coloured portion of the eye that lies anterior to the lens.
- consists of 2 layers of muscle (inner circular and outer radial smooth muscle)

Question 7

function of the choroid

Answer 7

absorbs excess light rays to prevent reflection and scattering of the light within the eyeball

Question 8

function of the fovea centralis

Answer 8

the area of greatest visual acuity containing only cones

Question 9

causes of glaucoma

Answer 9

increased pressure to the optic nerve can cause glaucoma- permanent vision loss

Question 10

what is a cataract?

Answer 10

medical condition where the lens of the eye becomes progressively opaque, resulting in blurred vision

Question 11

what is accomodation

Answer 11

the lens of the eye must become round in shape to view objects in close range

Question 12

define near point

Answer 12

the closest distance at which an object apears to be in sharp focus

Question 13

define visual acuity. what test would you use to determine visual acuity?

Answer 13

refers to the degree of sharpness of eyesight.
- standard test for determining this is the SNELLEN TEST- measured in a fraction. what you can see/ what the general population can see.

Question 14

hyperopic eye characteristics

Answer 14

caused by an eyeball that is too short.

• individual with this see distant objects clearly but but close objects are out of focus.
• need a converging lense to INCREASE refraction refer to notes for diagram

Question 15

myopic eye characteristics

Answer 15

caused by an eyeball that is too long

• can see close objects clearly but distant objects are blurry
• need a diverging lens to DECREASE refraction

Question 16

what is an astigmatism

Answer 16

an astigmatism is irregular curvature of the cornea/lense.

Question 17

what test would you use to predict colour blindness?

Answer 17

standard pseudoisochromatic colour blind test

Question 18

what does the external ear do?

Answer 18

collects sound waves and channels them inwards

Question 19

what does the middle ear do?

Answer 19

the middle ear transfers sound vibrations to the oval window and
- equalizes pressure with external atmospheric pressure

Question 20

what does the inner ear do?

Answer 20

contains the receptors for hearing and equilibrium

Question 21

what are the main subdivisions of the internal ear?

Answer 21

1) bony labyrinth

2) memranous labyrinth

Question 22

about the bony labyrinth:

Answer 22

bony labyrinth: system of chambers within the temporal bone that contains perilymph fluid.
-3 regions include 1) cochlea 2)vestibule 3) semicircular canals

Question 23

about the membranous labyrinth:

Answer 23

membranous labyrinth lies within the bony labyrinth and consists of interconnecting sacs and ducts filled with endolymph fluid.
- receptors for hearing are located within the cochlear duct while the recepters for equilibrium are located within the saccule, utricle (static eq.) and semicircular ducts (dynamic eq.).

Question 24

about equilibrium

Answer 24

equilibrium sensations provide information about the position of the head in space by monitoring gravity, acceleration, and roation.
- has 2 components: static and dynamic equilibrium

Question 25

vestibule

Answer 25

has receptors involved in maintaining static equilibrium

Question 26

what is middle ear deafness?

Answer 26

a loss of hearing from failure to conduct sound waves and vibrations from the outer to inner ear

• weber test tests for middle ear deafness
• rhine test- holding it against the mastoid process which measures bone conduction

Question 27

taste

Answer 27

a chemical taste first dissolves in saliva and then stimulates the hairs of taste cells that emerge from a taste pore in the taste bud.
5 primary tastes: sweet - from sugars, sour - citric acid, bitter-caffeine, salty- metal ions like sodium or potassium, umami- meaty/savoury taste