2.1.5 Plasma Membranes Flashcards Preview

A Level Biology > 2.1.5 Plasma Membranes > Flashcards

Flashcards in 2.1.5 Plasma Membranes Deck (10)
Loading flashcards...
1
Q

Plasma membrane

A

Phospholipid bilateral

Hydrophilic phosphate heads
Hydrophobic fatty acid tail core

2
Q

Compartmentalisation

A

The formation of seperate membrane-bound areas in a cell

3
Q

Fluid mosaic model

A

Phospholipids drew to move within layer

Proteins embedded in the bilayer

4
Q

Intrinsic proteins

A

Embedded in both layers

Hydrophobic R-groups on surface

5
Q

Factors affecting membrane structure

A

Temp: increases KE so moves more. Loses structure and proteins denature

Organic solvents: will dissolve membranes, become leaky

6
Q

Diffusion

A

The net movement of particles from a region of higher concentration to a region of lower concentration

Down a conc gradient

Passive

7
Q

Active transport

A

Movement of molecules/ions from lower to higher concentration
Against a concentration gradient

Requires energy — active

8
Q

Transport

A

Bulk transport: large molecules

Endocytosis: into cell

Exocytosis: out of cell

9
Q

Osmosis

A

The movement of water from high to low concentration down a water potential gradient

10
Q

Water potential

A

The pressure exerted by water as they collide with a membrane or container