Lab Quiz #2

Question 1

receptive fields

Answer 1

• the area surrounding cutaneous touch receptors where they can detect stimuli
• there’s an inverse relationship between the density of receptors & the size of primary receptive fields
• more receptors there are, the smaller their individual receptive fields are

Question 2

rod cells

Answer 2

• photoreceptor cell in eye
• located more in peripheral areas
• high sensitivity
• work under low light conditions of night
• more light sensitive than cones
• light sensitive region points away from light/toward back of eye

Question 3

cone cells

Answer 3

• photoreceptor cells in eye
• densely concentrated in the fovea
• respond to bright light
• responsible for color vision
• 3 types - blue, red, & green
• color blindness due to lack of one cone type

Question 4

3 layers of cells - from front to back

Answer 4

1. ganglion cells - axons merge to form OPTIC NERVE (which passes thru OPTIC DISC)
2. bipolar cell layer - layer establishes pathways for nerve impulses; (bipolar cells, amacrine cells & horizontal cells)
3. ganglion cells - only receptor cells w/action potentials

Question 5

Fovea

Answer 5

• location of highest acuity

- only cones located here

Question 6

Light sensitive pigment in rods

Answer 6

rhodopsin

Question 7

What is rhodopsin comprised of?

Answer 7

opsin & retinal

Question 8

ciliary body

Answer 8

• consists of ciliary muscle & capillary network that produces the aqueous humor

Question 9

ciliary muscle

Answer 9

a circular ring of smooth muscle attached to the lens by SUSPENSORY LIGAMENTS

Question 10

what does stimulation from the sympathetic system do to the pupil?

Answer 10

• ciliary muscle relaxes
• muscle ring is more open
• increases tension on suspensory ligament
• lens is flattened
• pupil dilates

Question 11

iris

Answer 11

• controls the light entering the eye

- 2 rings of muscle ( circular & radial)

Question 12

role of lens

Answer 12

• when object is far - little refraction needed. Parallel lines come in & bent to focal point
• when object is close - stronger/rounder lens needed to make the light converge on focal point. Light is still diverging when it enters eye

Question 13

accommodation

Answer 13

ability to adjust the strength of lens by chaining its shape (making it rounder)

Question 14

what does lens do under parasympathetic stimulation?

Answer 14

• ciliary muscles contract
• muscle ring gets smaller
• releases tension on suspensory ligament
• lens is rounder
• pupil gets smaller

Question 15

myopia - eyeball too long or lens too strong

Answer 15

• nearsightedness
• far light is focused in front of the retina = blurry
• correct with a CONCAVE lens

Question 16

hyperopia - eyeball too short or lens too weak

Answer 16

• farsightedness
• near objects are focused behind the retina = blurry
• correct with a CONVEX lens

Question 17

blind spot (aka optic disc)

Answer 17

• point at which optic nerves leave & through which blood vessels pass
• contains no rods or cones

Question 18

Two sensory systems of ear:

Answer 18

1. cochlea - contains receptors for conversion of sound wars into nerve impulses
2. vestibular apparatus - necessary for sense of equilibrium

Question 19

external ear is composed of:

Answer 19

1. pinna - large flap of ear
2. ear canal
3. tympanic membrane - thin membrane that separates the external & middle ear

Question 20

eustachian (auditory) tube

Answer 20

connects the middle ear to the pharynx

Question 21

middle ear transfers the vibrating movements of the tympanic membrane to the fluid of the inner ear via:

Answer 21

ossicles
1. malleus - attached to the tympanic membrane
2, incus - between two bones
3. stapes - attached to the oval window, entrance to the fluid-filled cochlea

Question 22

perilymph

Answer 22

fluid within the scala vestibuli & scala tympani

Question 23

endolymph

Answer 23

fluid within the cochlear duct

Question 24

sympathetic nervous system

Answer 24

“Fight or Flight”

• Prepares body for strenuous physical activity
• part of the Autonomic System -> Efferent System -> PNS

Question 25

parasympathetic system

Answer 25

“Rest & Digest

• dominates in quiet, relaxed situations
• part of Autonomic System -> Efferent System -> PNS

Question 26

Cranial Nerve 1

Answer 26

Oh (Olfactory)

Question 27

Cranial Nerve 2

Answer 27

Oh (Optic)

Question 28

Oh, Oh, Oh, They Traveled And Found Voldemort Guarding Very Ancient Horcruxes

Answer 28

12 Cranial Nerves

1. Olfactory - smell
2. Optic - vision
3. Oculomotor - eye movement
4. Trochlear - eye movement
5. Trigeminal - somatosensory info from face; chewing
6. Abducens - eye movement
7. Facial - taste, facial expressions, somatosensory fr. ear
8. Vestibulocochlear - hearing; balance
9. Glossopharyngeal - taste, tongue; some swallowing
10. Vagus - viscera, glands, heart rate
11. Accessory - head movement
12. Hypoglossal - tongue