Epithelium

Question 1

Epithelium definition

Answer 1

tissue containing layers of cells lining the outside and inside cavities of the body

Question 2

Functions of the epithelium

Answer 2

innate immune system, exchange of nutrients, gas, waste products, water, drug delivery route

Question 3

Features which protect skin

Answer 3

tight junctions, longitudinal flow of air, fatty acids, antibacterial peptides, normal flora

Question 4

Features which protect the gut

Answer 4

tight junctions, longitudinal flow of fluid, low pH, enzymes (pepsin), antibacterial peptides, normal flora

Question 5

Features which protect the lungs

Answer 5

tight junctions, movement of mucus by cilia, antibacterial peptides

Question 6

Features which protects the eyes/nose

Answer 6

tight junctions, tears, nasal cilia, enzymes in tears (lysozyme)

Question 7

Pseudostratified columnar

Answer 7

removal of dust and particles from airways, has cilia, forms mucous membrane, lines the respiratory passageways

Question 8

Simple columnar

Answer 8

absorption, lines uterus and most GI organs

Question 9

Simple cuboidal

Answer 9

secretion and absorption, in glands, kidney tubules, ovaries

Question 10

Simple squamous

Answer 10

diffusion and filtration, in lungs, walls of capillaries and vessels

Question 11

Stratified squamous

Answer 11

protection of underlying cells, new cells pushed towards surface, in skin, throat, vagina, mouth

Question 12

Stratified cuboidal

Answer 12

protection, lines ducts of mammary glands, sweat glands, pancreas

Question 13

Stratified columnar

Answer 13

protection, secretion, in male urethra, vas deferens, parts of pharynx

Question 14

Transitional epithelium

Answer 14

stratified epithelium with mixed shapes, lines urinary tract particularly bladder

Question 15

Epidermis

Answer 15

waterproof, UV protection, 5 sub-layers, non-vascular

Question 16

Cells of epidermis

Answer 16

keratinocytes, langerhan cells, melanocytes, merkel cells

Question 17

Dermis

Answer 17

connective tissue, cushions body, vascular, innervated, hair follicles

Question 18

Dermis glands

Answer 18

lipids/proteins, water/salt

Question 19

Hypodermis

Answer 19

(aka subcutaneous layer) lowermost layer, contains fibroblasts, adipocytes, macrophages

Question 20

Keratinocytes

Answer 20

main cell type, differentiate through layers, form squamous cells, contain keratin, barrier function

Question 21

Langerhan cells

Answer 21

sense foreign organisms, take up antigen, travel to lymph nodes to activate immune response

Question 22

Melanocytes

Answer 22

in basal layer of epidermis, contain melanin - skin colour, UV protection

Question 23

Merkel cells

Answer 23

in basal layer of epidermis, involved in sensing touch

Question 24

Dermatitis

Answer 24

inflammation of the skin eg. atopic dermatitis/eczema, contact dermatitis - treatment: corticosteroids, anti-histamines

Question 25

Viral warts

Answer 25

benign tumour caused by papillomavirus - treatment: anti-virals

Question 26

Acne

Answer 26

excessive secretion of oils from sebacious glands, dead skin cells plug pores - treatment: exfoliation, topical anti-bacterials

Question 27

Carcinomas

Answer 27

cancers arising from epithelial cells, most common cancer - includes prostate, breast, lung and bowel cancer

Question 28

Environmental cancer triggers

Answer 28

sunlight, smoking, viruses

Question 29

Basal cell carcinoma

Answer 29

most common skin cancer, develops in basal cell layer of epidermis, due to chronic exposure of sunlight

Question 30

Squamous cell carcinoma

Answer 30

second most frequent, develops in top layer of epidermis, cause, sunlight, skin injury

Question 31

Malignant melanoma

Answer 31

aggressive and life-threatening, develops in melanocytes, high tendency to spread, early detection important