Epithelial Cells

Question 1

Epithelia definition

Answer 1

Sheets of contiguous cells of various embryonic origin, that cover the external surface of the body and line internal surfaces

Question 2

What are epithelial tissue derived from?
Give detail

Answer 2

The germ layer

Ectoderm - epidermis (outer layer of skin)
Endoderm - GI tract
Mesoderm - inner body cavities

Question 3

What is the basement membrane made of?
Function? (3)

Answer 3

Basal lamina and reticular layer
Filter, cell attachment, physical support

Question 4

What do goblet cells have on them?

What do they release?

Answer 4

Microvilli - NOT cilia

Mucins - through exocytosis

Question 5

What causes more water to be in the mucin released by goblet cells?

Answer 5

Increased release of ions

Question 6

How do you identify keratin in an image?

Answer 6

No nucleus

Lateral surface

Question 7

What is the stratum corneum?

Answer 7

Outermost layer of the epidermis

Question 8

How do goblet cells release mucin?

Answer 8

Exocytosis

Question 9

What gene is mutated for a patient with cystic fibrosis? What does this cause?

Answer 9

CFTR

Cl- not released, sticky immovable mucus

Question 10

What is the membrane that some organs are surrounded by?

Answer 10

Serous membrane

Question 11

What is the name of the serous membrane closest to organs?

Answer 11

Visceral

Question 12

What is the name of the serous membrane that lines the outer edge?

Answer 12

Parietal

Question 13

Why are the lungs shiny?

Answer 13

They are covered by moist pleura (thin layer of tissue)

Question 14

What do the mucous and serous membranes line?

Answer 14

M - internal tubes which open to the exterior

S - closed body cavities !which do not open to the exterior!

Question 15

Give examples of what mucous and serous membranes line

Answer 15

M - GI tract, respiratory tract, urinary tract

S - peritoneum (abdominal organs), pleural sacs (lungs), pericardial sacs (heart)

Question 16

What is a similarity mucous and serous membranes

Answer 16

Both carry blood and lymphatic vessels + nerves

Question 17

Role of keratin

Answer 17

Prevents water loss
Protects against abrasion

Question 18

Role of cilia

Answer 18

Control micro movements of luminal contents

Question 19

Role of goblet cells

Answer 19

Secrete mucus
Moisten
Lubricate

Question 20

Role of microvilli

Answer 20

Increase surface area for absorption and secretion

Question 21

Role of club cells

Answer 21

Protect bronchioles
Act as stem cells for respiratory epithelium

Question 22

Role of micro fold cells

Answer 22

Allow rapid sampling of gut micro flora

Question 23

Role of stereocilia

Answer 23

Convert pressure waves into electrical signals - in the auditory system

Question 24

Where are club cells found?

Answer 24

Airway side of the terminal bronchioles

Question 25

How do club cells protect the bronchioles?

Answer 25

Secrete a variety of products - like uteroglobin Detoxify harmful substances inhaled - using cytochrome P450 enzymes

Question 26

Where are microfold cells found?

Answer 26

Small intestines, close to lymphatic nodules

Question 27

Describe how microfold cells function

Answer 27

1. Trap pathogens and molecules 2. Present to dendritic cells 3. Present to lymphocytes and macrophages - immune response or digestion occur

Question 28

Key downside of microfold cells

Answer 28

Pathogens use them as a point of entry

Question 29

What specific type of organelles are stereocilia, for hair cells?

Answer 29

Mechanosensing

Question 30

How do stereocilia assist hearing and balance?

Answer 30

They respond to fluid motion

Question 31

How are stereocilia linked to sperm?

Answer 31

Facilitate absorption of the residual sperm body after spermiation has completed

Question 32

What do stereocilia contain that assists them with movement?

Answer 32

Actin and myosin

Question 33

Which cells do not renew for smokers?

Answer 33

Club cells

Question 34

What are the three early stages of smoking damage?

Answer 34

1. Thickened mucus layer 2. Cilia die 3. Ciliagenesis

Question 35

What are the four steps to chronic damage when smoking?

Answer 35

1. Goblet and basal cells proliferate 2. Club cells die 3. Carcinogens induce mutations 4. Pneumocytes in the alveoli die

Question 36

Name four common conditions related to smoking

Answer 36

Asthma Chronic bronchitis Emphysema COPD

Question 37

What is COPD?

Answer 37

Emphysema and chronic bronchitis

Question 38

What is acute bronchitis?

Answer 38

Reduced lung function due to inflammation, excess mucus and swelling

Question 39

What is chronic bronchitis?

Answer 39

Start of or irreparable damage to the bronchioles and alveoli

Question 40

What is emphysema?

Answer 40

Permanent widening of airspaces distal to the terminal bronchiole without fibrosis - loss of elastic recoil

Question 41

What is asthma?

Answer 41

Caused by bronchospasm, obstruction form mucus and narrowing of airways Leads to variable expiratory airflow - amongst other symptoms!

Question 42

When are epithelial cells polarised?

Answer 42

When at surfaces

Question 43

What are epithelial cells held together by?

Answer 43

Anchoring proteins

Question 44

What is a contractile epithelial cell?

Answer 44

Myoepithelial