Sensory Reception (exam)

Question 1

What are sensory receptors?

Answer 1

Cells or nerve endings sensitive to stimuli which translate messages into impulses in sensory neurons.

Question 2

What is a sensation?

Answer 2

The cerebral cortex’s response to information.

Question 3

What is perception?

Answer 3

How the cerebral cortex interprets impulses.

Question 4

What is sensory adaptation? Where would it occur?

Answer 4

The brain’s method of filtering out unnecessary stimuli. It would occur in the thalamus.

Question 5

What are the 4 types of receptors?

Answer 5

Chemoreceptors, mechanoreceptors, thermoreceptors and photoreceptors.

Question 6

What is the Sclera? What is it’s purpose?

Answer 6

The outermost layer of the eye. It provides the eye with protection and support.

Question 7

Where is the cornea? What is it? What is it’s purpose?

Answer 7

The cornea is a clear section of the sclera. It is the portion of the eye where light enters.

Question 8

Where does the cornea get nutrients from?

Answer 8

Since the cornea has no blood vessels, it receives it’s nutrients and oxygen from the atmosphere with tears.

Question 9

Where is the choroid? What is it’s purpose?

Answer 9

The choroid in the intermediate layer of the eye. It is pigmented to prevent light from scattering in the eye, absorbing stray light rays.

Question 10

Where is the iris? What is it?

Answer 10

The iris is in front of the choroid at the front of the eye. It regulates the amount of light entering the eye. Everyone has a unique iris.

Question 11

Where is the pupil? What does it do?

Answer 11

The pupil is in the middle of the iris. It contracts and expands to allow more or less light into the eye.

Question 12

Where is the Lens? What does it do?

Answer 12

The lens is found behind the choroid. It changes shape to focus images at the retina.

Question 13

How does the lens change shape?

Answer 13

Ciliary muscles in the eye contract the lens to make it rounder, while suspensory ligaments hold ciliary muscles in place and tighten to flatten the lens.

Question 14

Where is the retina? What does it contain?

Answer 14

The retina is the innermost layer of the eye. It contains rods and cones which are the photoreceptors of the eye.

Question 15

What are rods sensitive to?

Answer 15

Rods are sensitive to light and dark.

Question 16

What are cones sensitive to?

Answer 16

Cones are sensitive to colour. They are focused in the middle of the retina, in the fovea centralis.

Question 17

Where is the macula? What is it?

Answer 17

The macula is in the Center of the retina. It contains the most cones in the eye. It is also referred to as the fovea centralis.

Question 18

Where does the optic nerve connect to the eye?

Answer 18

It connects at a point in the retina called the blind spot.

Question 19

Where is the aqueous humour? What is it’s purpose?

Answer 19

The aqueous humour is found between the lens and cornea. It drains daily and provides surrounding cells with nutrients while maintaining the eyes shape

Question 20

Where is the vitreous humour? What is it’s purpose? What is it’s consistency?

Answer 20

The vitrious humour is found behind the lens in the major part of the eye. It maintains the eyes shape and supports surrounding cells. It is jelly-like, 99% water and 1% collagen. It never drains and is responsible for eye floaters.

Question 21

What are eye floaters?

Answer 21

Eye floaters are neutrally bouyant clumps of collagen that form in the eye after many years.

Question 22

What does image initially look like when it enters your eye?

Answer 22

The image is initially upside down and inverted.

Question 23

What is accommodation?

Answer 23

Accommodation is the eye changing the shape of its lens to focus images.

Question 24

What does the lens do when focusing on near objects?

Answer 24

The lens becomes rounder as the ciliary muscles contract to increase the curvature.

Question 25

What does the lens do when focusing on far objects?

Answer 25

The lens flattens as ciliary muscles reflex and suspensory ligaments tighten to decrease curvature.

Question 26

When is the image processed in the eye? Where?

Answer 26

The image is processed once it reaches the retina and rods and cones are able to process the light and darkness, along with colour of the image.

Question 27

What happens to Rods and cones when no image is present?

Answer 27

Rods release rhodopsin and cones release photopsin. Comes release photopsin. They are in hibitorg neurotransmitters.

Question 28

What happens to rods and cones once light hits them?

Answer 28

Rhodopsin and photopsin break down, allowing impulses to be sent to bipolar neurons, which pass on to the ganglion and eventually to the optic nerve.