Animal Tissues Flashcards
(218 cards)
Which part of epithelial cell gets modified and what are the modifications
Apical part
1.microvilli
2. Villi
3.kinocilia
4.stereo cilia
First phylum to exhibit tissue level of organisation
Cnidaria
Epithelial tissue cells are packed ______
Epithelial tissue nucleus position
Parts of an epithelial cell
1.Set close to eachother
With very less extracellular material in between
2. Central nucleus
3. Basal and apical
Apical end facing
Apical end modifications
1.Outer environment
2. Cilia- kinocilia stereocilia
Villi and microvilli
What is Basement membrane
The acellular part on which the basal part of epithelial cells rest and it is basically in between epithelial tissue and connective tissue
Basement membrane= ______+________
Basal lamina+ reticular lamina
Basal lamina is secreted by
Basal part of epithelium
Basal lamina is composed of
Mucopolysaccharides and glycoproteins
Reticular lamina location
Reticular lamina is secteted by
Reticular lamina is composed of
- Below the basal lamina
- Secreted by underlying connective tissue
- Collagen fibres and reticular fibres
Basement membrane composition
It is made up of mucopolysaccharides and glycoproteins and collagen fibres
And not cells hence acellular.
Basement membrane functions (2)
1.support to epithelial cells- anchorage to cells
2. Nutrient providing to cells via diffusion
Lack of basement membrane can cause-
Tumor cells due to metastasis of cells
The cells move around with no anchorage if basement membrane is absent
How are materials exchanged between epithelial cells?
Who helps in exchange of materials?
diffusion
basement membrane
Classification of epithelial tissue
Epithelial tissue : simple and compound
- Simple: squamous
Cuboidal
Ciliated
Columnar
Pseudeostratified - Compound: stratified and transitional
Stratified squamous and stratified cuboidal
Stratified squamous: keratinised and non keratinised
What is pavement epithelium
Why is it called that way?
Simple epithelium
These are closely fit with their neighbouring cells like tiles on floor
What is tessellated epithelium
Why is it called that way?
Simple epithelium
Because it forms the inner lining of lungs and alveoli as tessellation means covering a surface
What makes cuboidal cells different from columnar cells
Cuboidal cells: height < width
Columnar cells : height > width
What is the cells shape of
squamous epithelium
Cuboidal epithelium
Columnar eptihelium
Polygonal
Polygonal in outline cuboidal in vertical
Pillar like cells in Polygonal columns
Major functions of simple epithelium
- Absorption
- Secretion
- Protection (minor)
What are the major functions of compound epithelium
- Protection
- Has little role in absorption and secretion
Examples of simple squamous epithelium (6)
- Airsacs of alveoli
2.endothelium (inner layer) (like endothelium of blood vessel)
3.lymph vessel
4.outer layer of bowman’s capsule and peripheral part of inner layer of bowman’s capsule
5.mesothelium ( lining of body cavity)
Such as pleura of lungs
Pericardium of heart
Peritoneum of body cavity - Descending limb and thin ascending limb (lower part) of loop of Henley
Bowman’s capsule linings
Squamous : outer layer
Squamous : peripheral part of inner layer
podocytes : inner part of inner layer
Nucleus shape and position of
Squamous
Cuboidal
Coloumnar
nucleus based info:
1.skeletal muscles:
2.female gamete of plasmodium vivax:
Ovoid and central
Round and central
Elongated and basal
1.skeletal muscles: nucleus under sarcolemma
2.female gamete of plasmodium vivax: near feritlisation cone
examples of simple cuboidal epithelium:(8)
- thyroid follicles
- ducts of glands especially sweat glands
3.mammary glands - liver
5.acini part of pancreas
6.iris choroid and ciliary body of nephron - germinal epithelium