Integumentary System

Question 1

Layers of skin

Answer 1

1. Epidermis
2. Dermis
3. Stratum corneum
4. Stratum granulosum
5. Stratum spinosum
6. Stratum basale

Question 2

Epidermis

Answer 2

• stratified squamous keratinizing epithelial tissue
• no capillaries
• most abundant cell are keratinocytes

Question 3

Stratum corneum

Answer 3

• dead cells
• flattened membranous sacs filled with keratin
• water-resistant

Question 4

Function of stratum corneum

Answer 4

barrier to pathogens & chemicals

Question 5

Stratum granulosum

Answer 5

• flattened cells
• contain deteriorating organelles
• cytoplasm full of lamellated granules & keratohyalin granules

Question 6

What are lamellated granules?

Answer 6

Release lipids

Question 7

Stratum spinosum

Answer 7

• cells contain bundles of intermediate filaments

- intermediate filaments made of pre-keratin

Question 8

Stratum basale

Answer 8

• base of epidermis
• actively mitotic stem cells
• produce keratin protein
• contains living keratinocytes

Question 9

Function of living keratinocytes in stratum basale

Answer 9

• produced after injury to the skin occurs

- produces vitamin D

Question 10

Integumentary system consists of…

Answer 10

• skin
• hair follicles
• glands
• subcutaneous tissue
• sweat

Question 11

Hair follicles

Answer 11

• made of epithelial tissue
• produces keratin
• colour determined by melanin

Question 12

Function of hair follicles

Answer 12

• protection
• insulation
• keeps dust out

Question 13

Glands

Answer 13

• made of epithelial tissue
• exocrine glands
• sebaceous glands
• ceruminous glands

Question 14

Function of exocrine glands

Answer 14

• secrete directly into epidermis

Question 15

Function of sebaceous glands

Answer 15

• secrete sebum-lipid

- which inhibits bacteria growth and maintains the moisture of hair follicles

Question 16

Function of ceruminous glands

Answer 16

• secretes cerumen to prevent the drying of the ear canal

Question 17

Receptors

Answer 17

• found in the epidermis and dermis
• free nerve endings
• encapsulated nerve endings
• provides environmental information to the CNS

Question 18

Free nerve endings function

Answer 18

• senses pain, heat, cold and light tough

Question 19

Encapsulated nerve endings function

Answer 19

• sense touch and pressure

Question 20

Nail follicles

Answer 20

• nails produced via mitosis

- produce keratin

Question 21

Function of nail follicles

Answer 21

Protect fingers and toes

Question 22

Subcutaneous tissue

Answer 22

• made up of areolar connective tissue & adipose tissue
• contains many WBCs, collagen fibres & elastin fibres
• contains mast cells
• superficial fascia = connective tissue membrane

Question 23

Function of mast cells

Answer 23

• produce histamine & leukotrienes

- for inflammatory response

Question 24

Function of adipose tissue

Answer 24

• stores fat

- for protection (cushioning), energy & insulation

Question 25

Types of skin cells

Answer 25

1. Keratinocytes
2. Melanocytes
3. Langerhans cells
4. Merkel cells

Question 26

Keratinocytes

Answer 26

• contain keratin
• for protection & are waterproof
• most abundant cell in skin (90%)

Question 27

Melanocytes

Answer 27

• contain melanin
• determine skin colour
• absorb UV

Question 28

Langerhans cell

Answer 28

• differentiate from red bone marrow
• have a role in immunity as they can become APCs
• become damaged by UV
• move around the epidermis layer

Question 29

Merkel cell

Answer 29

• recognise tough sensation

- deepest layer of skin cells