Session 2- Epithelial Tissue Flashcards
What are the 4 basic tissue types?
Epithelial
Nervous
Muscle
Connective
What functions are epithelial tissues important for?
Protection Excretion Secretion Sensory Absorption Lubrication Reproduction Cleansing
True or false: Epithelia are vasculated
False- they are avasculated and rely on surrounding blood vessels that lie close to the BM to supply nutrients and oxygen
True or false: Epithelia are innervated
True- they have a nerve supply
There are three types of epithelia. What are they?
Simple epithelia
Stratified epithelia
Glandular epithelia
Simple epithelia can be further divided into three types, what are they?
Simple squamous
Simple cuboidal
Simple columnar
The basement membrane is made up of two fused layers. What are they?
Basal lamina
Reticular lamina
Name three apical specialisations
Villi
Cilia
Sterocilia
How are adjacent epithelial cells held together?
Tight junctions
Tight junctions create a (1)________ which is selective for (2)_________ and (3)__________. They divide the cell into two distinct regions: (4)__________ & (5)__________.
(1) barrier
(2) water
(3) solutes
(4) apical
(5) basal
What three function do tight junctions provide in epithelial cells?
Functional polarity
Regulation
Leakiness
What structures are responsible for direct communication between cells?
Gap junctions
Gap junctions communicate both ____________ and ____________
Chemically
Electrically
What are the two structures used to attach epithelial cells to the basement membrane?
Focal Adhesions
Hemidesmosomes
Focal adhesions and hemidesmosomes both use _____________ to to achieve their function.
Integrins
Focal adhesions link the _____________ to the ______ _______________ of cells for structural strength
Extracellular matrix
Actin cytoskeleton
Besides providing structural support, focal adhesions are also sites of _________ ______________.
Signal transduction
In response to adhesion
Focal adhesions play a prominent role in
1) providing structural strength
2) signal transduction
3) __________________
Cell migration in wound repair
Hemidesmosomes link (1)_____________ outside of the cell with (2)___________ ______________ (_____________) in the cell. This provides the cells with (3)__________________. They are found in tissues subject to (4)_______________.
(1) The extracellular matrix
(2) Intermediate filaments (Keratin)
(3) Structural support
(4) Abrasion
Describe the role of desmosomes?
To strengthen connections between adjacent cells in epithelia that needs to withstand high mechanical stress.
Give an example of where desmosomes may be important
Urinary bladder transitional epithelium
What are the main roles of integrins (3 roles)?
Attachment of cells to the ECM
Signal Transduction
Immune patrolling/ cell migration
List 5 types of cell communication
Autocrine Paracrine Endocrine Synaptic Neurocrine
Autocrine communication =
Communication with self
Paracrine communication=
Communication with adjacent cells
Endocrine communication=
Communication via hormonal secretion
Synaptic communication=
Communication via neurotransmitters
Neurocrine communication=
Communication via select molecules to nearby cells with receptors on
Cultured cells have a ____________ life span and therefore demonstrate ________________
Limited
Senescence
Name two methods of cell death
Apoptosis
Necrosis
Give three types of cell renewal and where in the body that type of renewal may be demonstrated.
(1) STATIC - CNS, heart, skeletal muscle cells
(2) STABLE- Fibroblasts, endothelium, smooth muscle cells
(3) RENEWING- Blood, skin epithelium, gut epithelium
