Membrane lipids I

how thick is the plasma membrane?

7.5 to 10nm

who proposed the fluid mosaic model and when?

SJ Singer and G Nicolson in 1972

…, also called … … describes the technique of breaking a frozen specimen to reveal … …

cryofacture, freeze fracture, internal structures

name two important membrane functions

compartmentalisation and scaffolding for biochemical activity

membrane rafts are an example of which plasma membrane function?

scaffolding for biochemical activity

Membrane rafts

1. … regions

2. more … and … packed

3. float …

1. specialised

2. ordered and tightly

3. freely

lipid rafts serve as … centers for the assembly of … molecules, playing vital roles in processes like … (name 3)

organising, signalling, signal transduction, membrane protein trafficking and neurotransmission

lipid rafts help … cellular processes by promoting interactions necessary for … and can influence membrane … and cell …

compartmentalise, signalling, fluidity, function

membrane rafts are lipid … enriched in … and …

lipid microdomains, cholesterol and sphingolipids

membrane rafts act as … platforms that regulate … and … efficiency of the … cascade in … cells

organising, spatial and temporal, phototransduction, photoreceptor

3 examples of membrane lipids

phospholipids, sphingolipids and cholesterol

what bond links glycerol and fatty acids in phospholipids

ester bond

what bond links sphingosine and fatty acids in sphingolipids

amide bond

what bond links glycerol and phosphate in phospholipids

phosphodiester bond

recent data indicates that phospholipid levels in the … decline with …

studies show up to a … reduction by age 80, potentially impacting …, … and … performance

brain, age

20%, memory, focus and cognitive

which molecule has H as the head group substituent

phosphatidic acid

A … is a broad class of lipids containing a phosphate group, while a … is a specific type of … that utilizes a glycerol backbone

phospholipid, glycerophospholipid

C1 of a glycerophospholipid usually contains a … FA either … or … in length (for example … acid)

C2 of a glycerophospholipid usually contains an … FA between … and … in length (for example … acid)

saturated, C16 or C18, palmitic

unsaturated, C16 and C22, oleic

the head group substituent can also be called a …

base

which phospholipids have the following bases (head group substituents)

1. choline

2. ethanolamine

3. serine

4. inositol

1. phosphatidylcholine

2. phosphatidylethanolamine

3. phosphatidylserine

4. phosphatidylinositol

phosphatidylcholine is the most … and provides …

phosphatidylethanolamine helps with membrane …

phosphatidylserine carried a … charge and is important in … (eg in …)

phosphatidylinositol can be phosphorylated to … which is central in cell … pathways

abundant, structure

curvature

negative, signalling, apoptosis

PIP2, signalling

which glycerol carbon is the phosphate linked to?

sn3

what does PIP2 stand for?

phosphatidylinositol 4,5 bisphosphate

what are the components of sphingolipids?

sphingosine and one fatty acid

what are the components of glycerophospholipids?

phosphate, glycerol, head group substituent and two fatty acids

the more saturated FAs there are the more … the membrane

the more unstaurated FAs the more … the membrane

rigid

fluid