Neural Lipids

Question 1

what is neural lipids?

Answer 1

Lipids found in the brain

Question 2

Nerve cells mould (modify) the lipid fabric (composition) of their
membranes to ease?

Answer 2

vesicle fusion, regulate ion fluxes and create
specialized microenvironment

Question 3

what are the function of membrane lipids?

Answer 3

controls
protein traffic, facilitates recognition between cells and leads to the
production of hundreds of lipid mediator

Question 4

is lipid solublle in water?

Answer 4

mostly, but not all of them

Question 5

what are lipids?

Answer 5

hydrophobic or amphipathic small molecules derived by condensation of hydrocarbon units in chains or rings

Question 6

what are the 4 catergories of lipids?

Answer 6

• fatty aclys(FA)
• glycerophospholipids(GP)
• sphinolipids (SP)
• sterol lipids (ST)

Question 7

Are fatty acids free in membranes?

Answer 7

never, but always attached to phospholipids and sphingolipids

Question 8

Which sphingolipid lacks glycerol and is the precursor to various complex sphingolipids?

Answer 8

Sphingosine.

Question 9

Identify the common sphingolipid that contains phosphocholine and is a major component of cell membranes

Answer 9

Sphingomyelin.

Question 10

What characterizes globosides in terms of sugar content?

Answer 10

Globosides contain 2 or more sugars

Question 11

what deficiency leads to Krabbe disease?

Answer 11

galactosylceramidase

Question 11

what is hugely toxic to oligodendrocytes and other cells?

Answer 11

accumulation of galactosylsphigosine

Question 12

What is the primary precursor of bile acids and steroid hormones in animals?

Answer 12

Cholesterol

Question 12

Name a major function of cholesterol in biological membranes.

Answer 12

controls membrane fluidity and packing, providing mechanical strength and supporting membrane organization and stability

Question 13

Where is the highest concentration of cholesterol found within the human body?

Answer 13

Approximately 25% of body cholesterol is located in the brain.

Question 14

In terms of solubility, describe cholesterol in water.

Answer 14

Cholesterol is water-insoluble.

Question 15

what are the function of lipids in neural lipids?

Answer 15

• insulating myelin to reduce ion leakage and speed up electrical
  signals
• Polarisation of neurons, vesicular trafficking at synapses
  (exocytosis)
• Rearranging dendritic spines to mediate synaptic plasticity

Question 16

what do paranodal junction do?

Answer 16

limits current leaks from the node of Ranvier

Question 17

How does the level of plasmalogens change with age, and at what point do they typically start to decline?

Answer 17

Plasmalogen levels increase with age up until 30-40 years and then decline with age.

Question 18

In what neurodegenerative condition has the loss of plasmalogens been correlated with the onset of dementia?

Answer 18

dementia in Alzheimer’s Disease (AD).

Question 19

What consequence arises in transgenic mice lacking plasmalogens, specifically concerning myelin and axons?

Answer 19

leads to demyelination, loss of myelin compaction, and axonal loss.

Question 20

what is the membrane fluidity depends on?

Answer 20

temperature

Question 21

How do the conical and inverted conical shapes of lipids minimize energy requirements for lipid packing in highly curved membrane structures?

Answer 21

by reducing curvature frustration

Question 22

what is the role of lipids in exocytosis?

Answer 22

Only in protozoa evidence of lipids involved in
fusion of vesicles

Question 23

what are the 2 membrane properties?

Answer 23

asymmetric and have specialised domain