Integumentary system

Question 1

2 major parts of this system

Answer 1

cutaneous membrane (skin)
Accessory structures

Question 2

Function of the integumentary system

Answer 2

• protection of underlying tissue
• maintains body temp.
• synthesizes vitamin D3
• stores lipids
• detects touch, pressure, pain and temperature
• excretes salts, water and organic wastes (glands)

Question 3

name the 3 main layers

Answer 3

epidermis
dermis
hypodermis (subcutaneous layer)

Question 4

What are the two types of skin of the epidermis that can be found

Answer 4

thin skin, covers most of the body (four layers)

thick skin, covers the palms of hands and soles of feet (five layers)

Question 5

what is keratinization and where does it occur

Answer 5

formation of a layer of dead, protective cells filled with the protein keratin, occurs on all exposed skin surfaces except eyes

Question 6

what is the skin life cycle

Answer 6

in 7-8 days, cells move from the innermost layer to the outermost layer of the skin and are shef off

Question 7

what does the dermis do?

Answer 7

anchors epidermal accessory structures

Question 8

what are the accessory structures of the dermis

Answer 8

hair, exocrine glands and nails

Question 9

what is the function of the hypodermis

Answer 9

connects dermis to underlying tissue and lies below and stabilizes the skin

Question 10

characteristics of hypodermis

Answer 10

elastic areolar and adipose tissue sare interwoven with the dermis, it has few capillaries and has no vital organs

Question 11

what are the functions of hair

Answer 11

• protects and insulates against UV and temperature changes
• guards body openings against particles and insects
• sensitive to very light touch which provide warning system

Question 12

name of the hair color pigment and what produces it

Answer 12

From the pigment melanin which is produced by melanocytes at the hair papilla and is determined by genes

Question 13

What does sebaceous glands do and what is its function

Answer 13

It discharges oily lipid secetion (sebum) into hair follicles

Sebum inhibits the growth of bacteria, lubricates hair and conditions surrounding the skin

Question 14

what is the function of sweat glands

Answer 14

cools skin, flushes microorganisms and harmful chemicals from skin

Question 15

what are nails made of an their function

Answer 15

kertainized epidermal cells that protect the tips of fingers and toes

Question 16

What are the factors that affect skin color

Answer 16

Epidermal pigmentation, namely the pigments carotene and melanin
Dermal circulationm, where oxygenated red blood contributes to skin color and cyanosis could result in a bluish skin tint due to reduction in blood flow/ oxygenation

Question 17

What is carotene

Answer 17

A orange yellow pigment found in orange vegetables.
It can be converted to vitamin A which helps in the normal maintenance of epithelial tissues and the synthesis of photoreceptor pigments in the eye (defincy causes night blindness)

Question 18

What is the importance of melanin

Answer 18

protects the skin from sun damage
UV radiation can cause DNA mutations and burns, leading to cancer and wrinkles
Skin colour depends on melanin production

Question 19

What is the cause of albinism

Answer 19

A defincy or absence of melanin production, albinos have photophobia/ sensitivity to the sun

Question 20

what is the effect of sunlight on the skin

Answer 20

The epidermal cels produce vitamin D3 (cholecalciferol) in the presence of UV radiation, which is converted to calcitrol in liver and kidneys and aids in the absorption of calcium and phosphorus
Insufficent vitamin D3 results in rickets or osteroporosis

Could also result in skin cancers like carcinoma, a cancer of epithelial cells and malignant melanoma, malignant (cancer cells) fomr in melanocytes and grow rapidly and metastasize through lympthatic system

Question 21

effects of aging on the skin

Answer 21

• sensitivity of immune system reduces
• skin infection and injuries become more common
• sensitvity to sun exposure increases
• skin becomes dry and scaly
• hair thins and change colour
• sagging and wrinkling of skin
• ability to lose heat decreases