Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BIOSCI 107 > Lecture 2: Epithelia > Flashcards

Lecture 2: Epithelia Flashcards

1
Q

Where are epithelial cells found

A

lining of hollow organs, cavities and ducts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Different types of cell junctions

A

Tight, Adherens, Gap, Desmosomes, Hemidesmosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Functions of Epithelial tissue

A

selective barrier - limiting the transfer of substances into the body
secretory surface - releases products onto free surfaces
protection - resists abrasion from the environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the apical surface

A

the outside world of the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the lateral surface

A

the vertical surface of a cross section

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the basal surface

A

the surface attached to the base membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are microfilaments

A

proteins made from actin, beneath cell membrane and cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Functions of microfilaments

A

Strength, alter cell shape, tie cells together, muscle contraction, link membrane to cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are intermediate filaments

A

predominant protein is keratin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Function of intermediate filaments

A

Strength, movement of materials through the cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where are tight junctions located

A

within the intercellular space of a cell membrane, joining cytoskeletons of adjacent cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the key binding proteins in a tight junction

A

Claudins and occludins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Function of tight junctions

A

Keeps the junction electrically tight, so ions and proteins cannot move between the cells - keeps cell polarity (prevents migration of proteins between basal and apical). Specific environment within the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the adherens junction

A

Sits below tight junction at the apex of the cell, has an intracellular gap - closer to the basal membrane. Has a layer of proteins to join actin to cadherins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Role of key protein cadherins

A

Spanning the gap, bind to actin to join the cytoskeleton to the skeleton of the membrane and adjacent cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Role of key protein catenins

A

Joins the cadherins to the microfilament actins

17
Q

Function of the Adherens junction

A

Key for cell stability, distributes tension forces around the cell to prevent cell seperation

18
Q

Describe a desmosome junction

A

Dome like structure with intercellular gap between the cell membranes on the lateral wall

19
Q

Key protein in a desmosome

A

Cadherin, the spanning protein

20
Q

Function of a desmosome

A

links cell surface to keratin (intermediate filament), creates structural integrity spanning from one desmosome to the other. Winds into keratin instead of locking into the actin. Binds muscle cells to prevent them pulling apart

21
Q

Where do the cell junctions bind

A

Into the cytoskeleton

22
Q

Composition of Gap Junctions

A

has connexIn protein molecules, 6 form a connexOn which can connect and open to form a hemichannel. Gap Junction = 2 hemichannels

23
Q

Function of Gap Junctions

A

hemichannel allows small molecules to pass between cells, key for communication and for contraction in the heart

24
Q

Where is the hemidesmosome located

A

It is a basal junction, on the basement membrane

25
Q

Function of the hemidesmosome

A

Linking of basal intermediate filament keratin to the basement membrane, connect epithelia to the membrane, locks cell down so it does not slide into the basement membrane

26
Q

Role of Integrin in the hemidesmosome

A

Linker protein (glycoprotein), spanning basement membrane to the inner part of cell. Binds to laminin in the membrane and keratin in the cytoplasm

27
Q

Two parts of the basement membrane

A

epithelia overlay the Basal Lamina and the retticular lamina. Found between the epithelium and connective tissues

28
Q

Composition of the basal lamina

A

Under the basal surface, secreted by the epithelial cells

29
Q

Composition of the reticular lamina

A

produced by the cells in the underlying connective tissue - the fibroblasts. Has no blood vessels. needs to allow the passage of nutrients through the basal lamina

30
Q

Exchange of nutrients in the epithelia

A

No blood vessels (avascular), exchange of nutrient takes place by diffusion

31
Q

Functions of the basement membrane

A

provides a surface for the migration of epithelial cells during wound healing, supports overlying epithelium, acts as a physical barrier to invasion, filtration of substances in the kidney

32
Q

Types of epithelial tissue

A

Covering and lining and glandular

33
Q

Description of covering and lining epithelia

A

outer covering of skin and internal organs, inner lining of blood vessels and body cavities

34
Q

Description of glandular proteins

A

the secretory portion of glands

35
Q

Function of endocrine glandular epithelia

A

secretion of hormones and precursors into the interstitial fluid, then blood

36
Q

Function of exocrine epithelia

A

secrete into passages/ducts and exterior surfaces

BIOSCI 107 (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions