Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BIOSCI 107 Part One > Cells and Tissues - Epithelial Tissue > Flashcards

Cells and Tissues - Epithelial Tissue Flashcards

1
Q

Epithelial tissue description

A

tissue that covers body surfaces, lines hollow organs, cavities and ducts, and forms glands

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

Cell junction definition

A

are contact points between the plasma membrane of tissue cells

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

Types of cell junctions

A

Tight junctions, Adherens junctions, Gap junctions, desmosomes and hemidesmosomes

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

Key functions of epithelial tissues

A 
Selective Barriers (limit uptake of anything into the interior or aid transfer)
Secretory (onto a free surface) 
Protective (it is the interface to the outside - also protects against abrasion)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Apical surface definition

A

the surface of an epithelial cell that is exposed to the body exterior or to the cavity of an internal organ

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

Lateral surface definition

A

the surface of an epithelial cell that is adjacent to other cells

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

Basal surface definition

A

is the bottom surface of an epithelial cell that is adjacent to the basement membrane

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

Types of Lateral junctions

A

Tight junction, Adherens junction, Gap junction and Desmosome

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

Types of Basal Junctions

A

Hemidesmosome

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

Microfilaments definition

A

are bundles of protein beneath the cell membrane and the cytoplasm eg. Actin

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

Microfilament function

A

To give cells strength, alter cell shape (act as cell skeleton), link the cytoplasm to the cell membrane, connect cells together, allow cell movement and muscle contraction

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

Intermediate filament

A

are a type of cytoskeletal element made of multiple strands of fibrous proteins wound together. These are thicker than microfilaments and made of proteins like keratin

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

Intermediate filament function

A

to provide strength to cell and allow materials to move through the cytoplasm

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

Definition of the lumen

A

the central cavity of a tubular or other hollow structure in an organism or cell (apical surface of a cell faces this)

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

Tight junction definition

A

a lateral junction that is made of individual sealing strands of transmembrane proteins

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

Where are tight junctions mainly found?

A

In the epithelial tissue that lines the stomach, intestines and urinary bladder (ie where you don’t want any leakage)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The main binding transmembrane proteins in tight junctions

A

Claudins and occludins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Adherens junction definition

A

a lateral junction that has a plaque layer of proteins on the inside of the cell to join actin to cadherins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Tight junction function

A

To maintain cell polarity by preventing the movement of ions and proteins between apical and basal surfaces of cells (they are electrically tight)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Cadherin definition

A

a transmembrane glycoprotein that joins cells together in adherens junctions and desmosomes.

These insert into the plaque on the opposite side of the plasma membrane, crossing the intercellular space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Plaque definition

A

a dense layer of proteins on the inside of the plasma membrane that attaches membrane proteins and microfilaments to the cytoskeleton

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Adhesion belt definition

A

The extensive adherens junctions in epithelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Catenins definition

A

a protein that links the Cadherins to Actin in adherens junctions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Actin definition

A

a microfilament in the cytoplasm of the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Adherens junction function
to prevent cell separation from tension forces like in contractions (eg. when food moves through the intestines)
26
Desmosome definition
a lateral junction that has a plaque layer on the inside to join keratin to cadherins
27
Keratin function in desmosomes
To given the cell structural integrity as keratin spans from one desmosome to another on the other side of the cell
28
Desmosome function
to prevent cells from separating/ pulling apart
29
Where are desmosomes mainly found?
In the epidermis (to stop separation from tension) and in cardiac muscle cells in the heart (to stop cells pulling apart during contraction)
30
Gap junction definition
a lateral junction that contains proteins that allow for communication between adjacent cells
31
Connexin definition
a membrane protein that forms connexons or hemichannels
32
Connexon/hemichannel definition
consists of 6 connexin protein molecules that make up a gap junction. These are closed and open when docked to a connexon of another cell.
33
Gap junction function
To allow small molecules and ions to diffuse from one cell to another. It also allows direct communication between cells
34
Hemidesmosome definition
a basal/basolateral junction that has a plaque layer and has transmembrane glycoproteins (integrin) that attach to the keratin of the cytoskeleton and the laminin of the basement membrane
35
Integrin definition
a transmembrane glycoprotein that links the keratin to laminin in hemidesmosomes
36
Laminin definition
a protein that is present in the basement membrane
37
Junctional complex definition
a combination of a tight junction, adherens junction and a desmosome
38
Basement membrane definition
is a thin extracellular layer that separates the epithelium from deeper tissue
39
The parts of the basement membrane
the basal lamina and the reticular lamina
40
Basal lamina definition
is the layer (in the basement membrane) closest to and secreted by the epithelial cells.
41
Hemidesmosome function
to connect the epithelial cells to the basement membrane
42
What is contained in the basal lamina layer of the basement membrane?
Proteins like collagen, laminin and glycoproteins and proteoglycans
43
Reticular lamina definition
the layer (of the basement membrane) closer to and produced by the connective tissue cells called fibroblasts
44
Fibroblast definition
collagen produced by connective tissue
45
What is contained in the reticular lamina layer of the basement membrane?
fibrous proteins such as collagen and fibronectin
46
Do epithelia have nerves or blood vessels?
Epithelia has nerves but is avascular (does not contain blood vessels). It exchanges nutrients and wastes through diffusion with blood vessels in adjacent connective tissue cells.
47
Basement membrane function
To support the overlying epithelium Provide a surface where epithelial cells can migrate during growth or wound healing (wounds disrupt epithelia and BM and need to be reconstituted during healing) Acts as a physical barrier (especially for malignant melanoma) Participates in the filtration of substances in the kidney
48
Metastasis definition
the growth of cancer in other secondary areas (the chance of this increases if malignant melanoma penetrates the basement membrane)
49
ABCD for melanoma
Asymmetry, border irregularity, colour and diameter
50
Two types of epithelial tissue
Covering/lining epithelia and glandular epithelia
51
Types of covering/lining epithelia
the outer coverings of skin and some internal organs the inner linings of blood vessels, ducts, cavities and the interior of the respiratory, digestive, urinary and reproductive systems
52
What is glandular epithelia?
the epithelia that constitute the secretory portion of glands
53
How are covering and lining epithelia classified?
by the arrangement of cells in layers and the shapes of the cells
54
Simple definition (in epithelia)
a single layer of cells
55
Simple epithelium function
diffusion, osmosis, filtration, secretion and absorption
56
Stratified definition (in epithelia)
two or more layers of cells
57
Stratified epithelium function
PROTECTION of underlying tissue in locations where damage may occur (considerable wear and tear)
58
Pseudostratified definition (in epithelia)
appears to have multiple layers of cells because the nuclei of the different cells are in different layers but because all cells connect to basement membrane it is in fact simple epithelium. Not all cells reach the apical surface
59
Goblet cells definition
Pseudostratified columnar cells that swell up with mucus
60
Pseudostratified epithelium function
Secretion
61
What are glandular epithelia?
Glands are made up of a single cell or group of cells that secret substances into blood
62
What are the two classifications of glandular epithelia?
Exocrine and Endocrine
63
Explain the process of exocrine glands?
Secrete substances or hormones into a duct which will then empty their contents onto a surface It produces local effects
64
What is an example of an exocrine gland working?
Sweat glands | Sweat is made in the dermis, it needs to get on the surface for thermoregulation, it does so through a duct
65
Explain the process of endocrine glands
Secrete substances or hormones directly into the blood via interstitial fluid (ie have NO ducts)
66
What is an example of an endocrine gland working?
Thyroid gland | Hormones migrate through the epithelia and straight into a blood vessel nearby
67
What are the two sub-types of exocrine glands?
Single cell or multicellular
68
What is a single cell exocrine gland?
Goblet cells | Secrete mucinin which is hydrated to form mucous
69
What are the two classifications for the DUCT of a multicellular exocrine gland?
Simple (has a single duct that doesn't divide) | Compound (duct that branches)
70
What are the classification of the SECRETORY portion of a multicellular exocrine gland?
Tubular if it forms tubes either straight or coiled | Alveolar if it forms sac-like pockets (roundish)
71
What are the 5 simple multicellular exocrine glands?
``` Simple tubular Simple coiled tubular Simple branched tubular Simple alveolar Simple branched alveolar ```
72
Where are simple tubular glands found?
Intestinal glands
73
What are simple coiled tubular glands used as?
Sweat glands
74
Describe simple branched tubular glands
Gastric glands | Mucous glands of oesophagus, tongue, duodenum
75
Describe simple alveolar glands
A stage in the embryonic development of simple branched glands
76
Describe simple branched alveolar glands
Sebaceous glands
77
What are the two subtypes of where simple squamous epithelium is located?
Endothelium and mesothelium
78
What does endothelium line?
Line blood vessels + heart (CVS system) | Barrier and allows for rapid diffusion
79
What does mesothelium line?
Pleura, Pericardial and peritoneal cavities (ALL SEROUS MEMBRANES) Secret serous fluid, especially to prevent friction in the heart
80
Where else is simple squamous epithelium found apart from the mesothelium and endothelium?
Alveoli of the lungs - rapid diffusion | Bowman's capsule of the kidney - filtration barrier
81
What is the function of simple squamous epithelium?
Diffusion (lungs), filtration (kidneys) and secretion (in serous membrane)
82
What is the function of the serous fluid?
To allow organs to 'slip and slide' past against each other without any friction
83
What is the function of stratified squamous epithelium?
PROTECTION
84
What are the two sub-types of stratified squamous epithelium?
Keratinised and non-keratinised
85
Where and what is the function of keratinised stratified squamous epithelium?
SKIN!! | Waterproof, protects from abrasion
86
Where and what is the function of non-keratinised stratified squamous epithelium?
Found in the 'naughty places' - mouth, tongue, throat, oesophagus, vagina and anus Protects from abrasion of mechanical/chemical stresses
87
What is the function of the simple cuboidal epithelium?
Secretion and absorption
88
Where is simple cuboidal epithelium found?
Pancreatic ducts (because pancreas secretes digestive fluids) Lens surface Kidney tubules Surface of the ovary
89
Where is stratified cuboidal epithelium found and what is its function?
Found in oesophageal glands, adult sweat glands and male urethra Protection, secretion, absorption
90
What are the modifications found on simple columnar epithelium?
Cilia and microvilli
91
What is the function of the cilia?
To move substances
92
What is the function of the microvilli?
Increase absorption through an increase in surface area

BIOSCI 107 Part One (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions