Cell Wall Flashcards
(14 cards)
Cell wall is composed of what in bacteria?
Peptidoglycan / murein
Cell wall is composed of what in fungi?
Chitin
Cell wall is composed of what in plant cell?
Cellulose, hemicellulose, pectin and protein
What is the main component of cell wall and in what form is it in?
Cellulose in form of microfabril and macrofibril
Composition of skeleton of cell wall
Microfibril and macrofibril
Composition of matrix of cell wall
Hemicellulose and pectin
Name the layers of cell wall
Middle lamella
Primary cell wall
Secondary cell wall
Tertiary cell wall
Middle lamella
Common layer between 2 adjacent plant cells
Made up of calcium pectate
Primary cell wall
Thinner than secondary cell wall
Since elastic and capable to grow, present in meristematic cells (they grow and divide)
Gradually diminishes as the cell matures
Made up of cellulose, hemicellulose, protein and pectin
Secondary cell wall
Thicker and more rigid than primary cell wall
Since not elastic and not capable to grow so found in permanent cells (mature and do not divide)
Towards the cell membrane than the primary wall (inner)
Made up of cellulose, hemicellulose, pectin and protein
Tertiary cell wall
Only present in tracheids of gymnosperms
Made up of xylan (polymer of xylose) and hemicellulose
Functions of cell wall
Provide shape to cell
Provide mechanical support (acts as an exoskeleton) and protects cell from mechanical damage and infections
Helps in cell to cell interactions
Acts as an barrier to undesired macro-molecules
When was the term plasmodesmata given and by whom?
Strassburger (1901)
What is plasmodesmata?
Cytoplasmic connection between 2 adjacent cells. Cell wall and middle lamella transversed by plasmodesmata and connects the cytoplasm of two neighboring plant cells.
