extracellular matrix// jims tissues and epithelia Flashcards
basic components of plant ECM
which is the cell wall
middle lamella, primary cell wall, secondary cell wall
sugar fibres in sugar background
basic component so of animal ECM
which is connective tissue
collagen and elastic fibres, ground substance
protein fibre in sugar background
~definition~
what is a ECM? (generalised)
(polysachharide or protein) fibres embedded in saccharide jelly-like matrix
How does the cell wall (ECM) of plant have high tensile strength?
it is strong due to turgor pressure
common feature/characterstics of ECM
high tensile strength
compression resistant as it can hold water
which of these is not a basic animal tissue epithelium muscle pancreas nerve
pancreas tissue!!
which of these is not a basic plant tissue dermal meristemic schlerenchymal vascular
OPTION C
> schelenchyma is ground tissue associated with xylem and phloem and gives structural support
whci tissue can give rise to a range of different plant tissue types (dividing, p/s, storage cells) collenchyma parencyma pavement cells phloem
OPTION B
makes up the ‘ground tissue’
why are epithleia made enetirely of cells?
A ECM not strong enog to fufill epithelia lfunction
B cells cannot syntesis ECM components
C form a pressure resistant enclosure to retain body fluid
D monitor and control transfer of materials betweenbody and its surroundingas
OPTION D
stratified epithelia are multilayered for what reason?
A allow easy transfer of materials form cell to cell
B early stage of epithelial development and eventually form a single layer
C surface cells can be damaged and worn away without affecting integrity of epithelial tissue
D allow secretion of basal lamina component s between cell layers
OPTION C
> ss. keratinised made of dead anucleate cells forming outer layer. tough, strongest AND waterproof covering
> s.s non-k has ALL layers living
which is not an epithelial function A absorption B dialysis C heat generation D protection E sensation F secretion
OPTION C
> dialysis means filtration!!
what is functional significance of collumnar epithelium?
A generate contractions to provide peristaltic movements
B make a thicker epithelium to protect underlying tissue
C provide lots of cytoplasm to power active transport
D prevent leakage across eputhlial layer
option C
> acive transport and absorption is key
>
Plant ECM fibres are made of A glycoprotein B glycosaminoglycan C polysaccharides D proteins
OPTION C
cellulose and hemicellulose crosslink to give a high tensile strength!
Animal ECM gel-like backgorund is made of A collagen B glycoprotein C glycosaminoglycan (GAGs) D hemicellulose
OPTION C
GAGs are long polysaccharide chains
> sulphated = larger Proteoglycans
> unsulphated = hyalonronic acid
why do plants wilt?
they lose their turgor pressure if not enough water