biological membranes Flashcards
Liposome
A ball of fats, hydrophilic head pointing outwards and hydrophobic tails pointing inwards. It happens when fats and water are shaken.
Glycoprotiens
carbohydrate tail attatched to protein.
Glycolipid
lipid with carbohydrate tail. Attatched to phopholipid head.
Ligand
A messanger that binds to a receptor.
Sterol
Type of lipid (think cholesterol)
ATP
adenosine triphosphate
ADP
adenosine diphosphate
Invagination
when the cell surface membrane dips to accomodate an incoming vesicle.
Phagacytosis
Describes movement of solids across a membrane.
Pintocytosis
describes movements of liquids across a membrane(think pint)
Crenation
A shrivelled animal cell. due to water loss (net movement of water out of the cell)
Cytolysis
An animal cell with too much water. the cell bursts.
Plasmalysed
Water moves out of a plant cell, leaving it shrivelled. this does not affect the cell wall.
Turgid
When a plant cell is rigid with water.
Balls of Lipid with the hydrophilic heads pointing outwards, hydropgobic tails pointing inwards
Lyposome
Name the roles of glycoprotiens and glycolipids?
- cell signalling ( as receptors)
- cell recognition (as antigens )
- stabalises membrane structure
What are antigens?
Markers that tell your immune system whether something is harmful or not.
What is the layer of glycoprotiens and glycolipids called?
GLYCOCALYX
what is a carrier protien that can transport two substances at once called?
A co- transporter
What is a co-transporter?
a carrier protein that can carry two substances at once.
what are the 3 functions of plasma membranes?
- cell identification
- compartmentalisation
- site of chemical reactions
What do solvents do to bilayer lipids?
Dissolve them!
Name the 3 types of receptors…
- receptors for neurotransmitters and hormones
- receptors for edocytosis
- receptors for adhesion and stability
Explain the glycocalyx and its link to adhesion?
The carbohydrate tails form hydrogen bonds with water molecules.
how does cholesterol regulate membrane fluidity?
prevents membranes from becoming too solid by stopping phospholipids from grouping together and crystallising.
two examples of reactions happening at the cell membrane.
- electron carriers and ATP synthase (enzyme) on the cristae of mitochondria (for the production of ATP)
- photosynthesis enzymes on stacks within the chloroplasts
glycolipids act as…
cell markers or antigens
glycoproteins
act as receptors
