the nose, tongue and skin

Question 1

what is the top of the nose made out of

Answer 1

The top of the nose is made up of two small bones while it tip is made of cartilage

Question 2

what is the upper part of the nose called? explain

Answer 2

the olfactory epithelium and it contains sensory receptors and neurons to transform an odour into a nerve impulse and conduct it to the brain for interpretation.

Question 3

To be detected by the sense of smell, a substance has to meet 4 conditions

Answer 3

1. They must contain chemicals to stimulate the receptor cells in the olfactory epithelium.
2. Be able to move through air.
3. Be concentrated enough.
4. Come in contact with receptor cells without being blocked.

Question 4

Stimulus —– receptor —– transformer —– conductor —– analyser

Answer 4

Odour molecule — receptor cells olfactory epithelium olfactory nerve brain

Question 5

what is the tongue made up of ? explain

Answer 5

Its made up of muscles covered with a layer of moist cells that form rough bumps called gustatory papillae (there are diff kinds of papillae). The vallate and fungiform papillea are made up of taste buds. The filiform papillea give the tongue its rough texture. There also taste buds on the palate, cheeks, pharynx, and epiglottis.

Question 6

Stimulus —– receptors —– transformer —– transporter —– analyser

Answer 6

Flavour tongue gustatory papillae gustatory nerve brain

Question 7

The tongue can only detect sapid molecules with one or more of the following flavours

Answer 7

sweet, salty, sour, bitter, and umami (savory)

Question 8

Substances can be detected by our taste buds only if what?

Answer 8

if they are coluble in saliva.

Question 9

explain sapid molecules

Answer 9

Sapid molecules stimulate the receptor cells of the taste bds which transform the flavors into nerve impulses. The nerve impulses travel through the cranial nerves to the brain stem and then to the brain to be analyzed.

Question 10

what layer of skin is the epidermis

Answer 10

outside layer

Question 11

what is the epidermis made up of

Answer 11

Made up of dead cells that are always flaking off and being replaced with new ones from underneath.

Question 12

what is the process of making new cells

Answer 12

mitosis

Question 13

what does the epidermis produce

Answer 13

Also produces keratin which boosts resistance and protects it from damage and germs.

Question 14

what large cells does the epidermis have

Answer 14

melanocytes, They are colored cells that produce melanin, brown pigment that protects the skin from the sun’s rays by absorbing UV rays.

Question 15

which layer of skin is the dermis

Answer 15

thickest layer of skin

Question 16

what does the dermis contain

Answer 16

Contains blood vessels that bring oxygen and nutrients to the skin cells and remove waste and carbon dioxide.

Question 17

Base of hair =

Answer 17

sebaceous glands that produce sebum (oil) that protects the hair and skin. Makes skin waterproof.

Question 18

Arrector pili muscle at base of hair does what

Answer 18

contracts to make hair stand up.

Question 19

what does dermis also contain

Answer 19

receptor cells, nerve endings, that are sensitive to pressure, pain and temperature.

Question 20

explain hypodermis

Answer 20

Bottom layer of skin is made mostly of fat mean to insulate the body in order to maitaine good body temperature.

Question 21

explain Sensory function of the skin:

Answer 21

Able to proceive sensations through the touch receptors in the skin (nerve endings).
Touch receptors are not evenly distributed throughout the body.
More receptors on fingers, lips, so the regions of the brain responsible to interpret sensory info from those areas take up more space.
Stimuli received by the sin are turned into nerve impulses by the nerve endings and travel through sensory neurons to the brain to be analyzed.