Biological Membranes Flashcards
What is the function of the cell membrane
Controls which substances enter and leave the cell
What does partially permeable mean
Only some substances are allowed through
How can substances move across the plasma membrane
Diffusion, osmosis and active transport
Name 2 other uses for the plasma membrane
Allow recognition by other cells , allow cell communication
What do cell membranes within the cell do
Act as a barrier between an organelle and the cytoplasm
What can cell membranes inside the cell provide
A vesicle for transport of substances between different areas
Membranes can be the site of what
Chemical reactions
What is the function of cholesterol
Helps stabilise membrane
What 3 molecules make up ATP
Adenine
Ribose
Phosphates
How does the fluid mosaic model describe the structure of plasma membrane
Phospholipid bilayer
Hydrophilic heads facing outwards and hydrophobic tails facing inwards
Define diffusion
The net movement of particles across a partially permeable membrane down the water potential gradient
Explain the importance of osmosis In plant support
Fills the vacuole
Pressure against the cell wall.
Determines if the plant is turgid or flaccid.
