The Sensory Receptors

Question 1

Functions of the parts of eye

Answer 1

Sclera
Protects the eye and gives it its shape.
Choroid
Supplies nutrients to the eye through blood vessels.
Retina
Receives photons and converts them into a nerve impulse.
Iris
Controls the amount of light entering through the pupil.
Pupil
Allows light to enter the eye.
Rods
Detect contrasts (black and white) but not color.
Cones
Detect color.
Macula
Translates light entering the eye into the images we see.

Question 2

The Control of the light entering the pupil

Answer 2

Light reflex
When a lot of light is entering the eye, the pupils constrict
When there’s less light entering the eye, the pupils dilate

Question 3

Dilated vs Constricted pupil

Answer 3

Dilated: Open, allowing more light.
Constricted: Smaller, allowing less light.

Question 4

Two types of of vision receptors

Answer 4

Rods: Black/white/contrasts.
Cones: Color.

Question 5

Path of Light through the Eye and Neural Impulse

Answer 5

Cornea
Aqueous humor
Pupil
Lens
Vitreous humor
Retina
Optic Nerve

Question 6

Nerve Carrying Neural Impulse to Visual Cortex

Answer 6

Optic Nerve

Question 7

Functions of Structures: Cornea, Aqueous Humor, Lens, Vitreous Humor

Answer 7

They allow light rays to travel to the retina, where they converge.

Question 8

Effects of Myopia, Hypermetropia, Presbyopia, and Astigmatism on Vision

Answer 8

Myopia: Nearsightedness, difficulty seeing distant objects caused by overly large eyeball or overly curved lens
Hypermetropia: Farsightedness, difficulty seeing close objects caused by smaller eyeball and insufficiently curved lens
Presbyopia: Farsightedness due to loss of lens flexibility.
Astigmatism: Blurred vision due to irregular cornea or lens curvature.

Question 9

Corrective Lenses for Myopia, Hypermetropia, Presbyopia, and Astigmatism

Answer 9

Myopia: Concave lenses.
Hypermetropia: Biconvex lenses.
Presbyopia: Biconvex lenses.
Astigmatism: Cylindrical lenses (limit refraction and concentrate light rays).

Question 10

Functions of the structures of the ear

Answer 10

Pinna: Captures sounds.
Auditory Canal: Carries sounds to the eardrum.
Eardrum & Ossicles: Amplify or tone down sound by transmitting vibrations to the inner ear.
Auditory Tube: Balances air on both sides of the eardrum.
Vestibule & Semicircular Canals: Provide information on the body’s position in space.
Cochlea: Transforms sound vibrations into nerve impulses.

Question 11

Travel of Vibrations through the Ear and Neural Impulse

Answer 11

Sound vibrations are received by the pinna.
They are then sent to the auditory canal.
They strike the eardrum
The vibration travels to the ossicles (hammer, anvil, and stirrup)
Then reaches the vestibule
The cochlea and cilia create the nerve impulse and the auditory nerve sends the nerve impulse to the auditory area of the brain

Question 12

Cerumen and Its Usefulness

Answer 12

Cerumen is earwax.
It protects the ear from infection and acts as a barrier to insects, water, and injury.

Question 13

Common Names of the Three Ossicles

Answer 13

Hammer anvil and stirrup

Question 14

What two structures are connected by the ossicles

Answer 14

The ossicles connect the eardrum and the cochlea

Question 15

Location of Receptor Organ for Sound

Answer 15

The Cochlea (fluid-filled)
attached to cilia

Question 16

Makeup of the Human Nose

Answer 16

Outer structures: cartilage
Inner structures: nostril and sinus and nasal cavity

Question 17

Olfactory Epithelium

Answer 17

The olfactory epithelium is the processor for olfaction.
It interfaces with the olfactory cortex, located at the top.

Question 18

Criteria for Detectable Odor

Answer 18

The substance must be an odorant.
It must be volatile, meaning it must be airborne.
The substance must be sufficiently concentrated to stimulate the olfactory cells.
It must come in contact with the cells of the olfactory epithelium without being blocked by nerves.

Question 19

Describe the makeup of the human tongue

Answer 19

The tongue and the gustatory papillae or taste buds

Question 20

What is a papilla? Where do we find taste buds?

Answer 20

Papilla is the receptor for taste, can be referred to as little nodes
Taste buds are all over the tongue, they are concentrated in the tips, sides and back surface

Question 21

What does sapid mean?

Answer 21

Substance has a taste

Question 22

What 4 criteria must be met in order for a substance to have a detectable flavour?

Answer 22

Must be sapid
Must be soluble
Must be sufficiently concentrated to stimulate the cells of the taste buds
Must come in contact with the taste buds of the gustatory papillae

Question 23

The 3 stimuli for skin

Answer 23

Pain, temperature, and pressure

Question 24

What are the two main layers of skin and what is beneath them?

Answer 24

The two main layers of skin are the epidermis and dermis. Beneath them is another layer called the hypodermis.

Question 25

Describe the general layout of the epidermis

Answer 25

The top layer of the epidermis consists of dead skin cells. In the middle, there are growing skin cells. Inside, there are new skin cells.

Question 26

What is melanin and why is it important?

Answer 26

Melanin is a pigment that gives color to the skin and protects it from the sun’s rays. It absorbs ultraviolet rays to reduce their harmful effects.

Question 27

Describe the layout of the dermis.

Answer 27

Thickest layer of ski, made up of collagen and elastic fibers, contains hair follicles, glands, receptors, nerve endings, and blood vessels

Question 28

What are the two types of glands found in the skin and describe each of them?

Answer 28

The two types of glands are sweat glands and sebaceous glands. Sweat glands excrete sweat to regulate body temperature, while sebaceous glands connect to the hair follicle and produce sebum to protect the hair and skin.

Question 29

What is the function of sebum? What is the function of the arrector pili muscle?

Answer 29

Sebum moisturizes the skin, protects it from the outside, and makes it waterproof. The arrector pili muscle causes goosebumps and raises the hairs to trap heat.

Question 30

What are some other functions of the skin?

Answer 30

Protection of the body: Protection from bacterial attacks, sebum allows for waterproofness, and melanin pigments protect skin from ultraviolet rays
Regulation of body temperature: Through excretion of sweat, body limits heat loss. Adipose tissue insulates the body from low temperatures.
Excretion of certain substances: Sweat glands secrete sweat which contains urea, excess water, and minerals
Production of Vitamin D: skin contains cholesterol, when it is exposed to the sun’s rays, the cholesterol turns into Vitamin D