Euakaryotic Cell - Cell Wall and Plasmadesmata - Part 5

Where is cell walls found?

outside plasma membrane

Since it’s found outside plasma membrane what is it classed as?

not an organelle

What it cell walls made from?

large chains of carbohydrates called cellulose. Fibre like.

1. What are the characteristics of the chains in cell walls?

2. What are the chains held together by?

1. Strong and criss-crossed

2. a protein called pectin

What does pectin (type of protein) give the chain?

strength

What does the cell wall prevent?

prevents the cel bursting when water enters the cell by osmosis

What does the cell wall allow?

large pressure in plant cell. Reinforces sometimes for extra strength

1. Where is pectin also found?

2. What does it do there?

1. in the middle lamellae

2. it cements one cell to another

1. Function for cell wall?

2. How does this work?

1. Transport

2. gaps between the cellulose fibres make the cell wall permeable to water and dissolved molecules and ions

What is this route of movement (through the cell wall) called?

apoplast pathway

1. Another function of the cell wall?

2. What happens?

1. Mechanical strength and support

2. when the vacuole is full or the cytoplasm pushes against the cell wall it resists exapnsion and the cell becomes turgid

What is plasmodesmata?

strands of cytoplasm

How many strands of cytoplasm equals to one plasmodesmata?

1

What does plasmodesmata do?

link cell to cell and pass through pores in the cell walls

What is known about this area?

there is no cellulose thickening between 2 cells and there is a strand of cytoplasm running from one cell to the next.

1. Function of plasmodesmata?

2. What does it allow?

1. communication between cells

2. allows water and dissolved ions and molecules to move between cells in a plant

What is this known as?

the symplast pathway