Tissues Flashcards
What best describes embryonic stem cells?
Pluripotent.
What are the two types of stem cells?
- Embryonic stem cells.
2. Adult stem cells.
What are the four types of tissue?
- Epithelia.
- Nervous.
- Muscle.
- Connective.
What is the purpose of the basement membrane?
- Separates the epithelial tissue with the underlying tissue.
- Anchors epithelial cells by having proteins which links to the surface of these cells.
- Contains filamentous proteins for strength.
What is the function of epithelial tissue?
PESS
- Protection of deeper tissues.
- Exchange of chemicals between underlying body cavity.
- Secretion of hormones.
- Sensation.
What is a carcinoma?
Tumour which develops from epithelial tissue.
What happens in cystic fibrosis?
Defective epithelial chloride ion transport.
What happens in cholera?
Increased activity of epithelial chloride ion transport in GI.
Where in the body would you find:
- Simple squamous
- Stratified squamous
- Simple cuboidal
- Stratified cuboidal
- Simple columnar
- Pseudostratified columnar
- Transitional
- Blood vessels
- Skin.
- Kidney tubule
- Reproductive system
- GI tract
- Respiratory system.
- Bladder.
What is special about transitional epithelia?
Can contract and expand due to distension.
What is desquamation?
Shedding of outermost layer of skin, replaced by basal cells which rapidly divide by mitosis.
Three cell types in Pseudostratified ciliated columnar epithelium?
- Columnar cells.
- Goblet cells.
- Basal cells.
Four types of cell junctions?
- Gap junction.
- Tight junction.
- Adhering junction.
- Desmosome.
How are gap junctions formed?
- 6 connexin molecules form a connexon.
2. Alignment of connexon molecules from opposing cells, forming a channel.
How are tight junctions formed?
- Membrane proteins claudin and occluding.
2. Interact with actin.
What is the function of tight junctions?
BFG
- Barriers - separating different compartments.
- Fences - maintain asymmetric distribution of lipids and proteins in the apical and basal membrane.
- gates - allows some molecules to flow more easily than others.
How are adherent junctions formed?
- Cadherin molecules bind to each other on adjacent plasma membranes of cells.
- Catenins bind to actin in cytoskeleton.
How are desmosomes formed?
- Cadherin molecules bind to each other on adjacent plasma membranes of cells.
- Catenins bind to intermediate filaments.
Two types of cell - matrix junctions?
- Hemidesmosomes.
2. Focal adhesions.
How are hemidesmosomes formed?
- Integrin bind to keratin in the cytoskeleton.
2. Integrin bind to laminin in extracellular matrix.
How are focal adhesions formed?
- Integrin binds to alpha actinic in cytoskeleton.
2. Integrin binds to laminin in extracellular matrix.
Glial cells in CNS?
- Oligodendrocytes.
- Astrocytes.
- Microglia.
- Ependyma
What are the functions of glial cells in CNS?
- Myelination.
- Metabolic and mechanical support and detoxification.
- Macrophages.
- Producing CSF and lining cells of CNS, acting as a reservoir for neuro-regeneration.
Glial cells in PNS?
- Schwann cells.
2. Satellite cells.
