lipid and bio membrane

Question 1

Major main class of biomolecule

Answer 1

1 amino acids
2nucleotides
3. Monosaccharides
4. Lipids

Question 2

Types of lipids

Answer 2

1.fatty acids
2.triglycerols
3.glycerophospholipids
4. Sphingolipids
5. Steroids
6. Other

Question 3

Amphipathic lipids

Answer 3

Any lipid that has a hydrophilic head and a hydrophobic tails

Question 4

Hydrophilic head?

Answer 4

Usually a phosphate group (charged)

Question 5

hydrophobic tail?

Question 6

Where we see hydeophobic effect?

Answer 6

1.protein folding
2.bilayer

Question 7

Lipids diffusion within bilayer

Answer 7

1.lateral diffusion
2.rotation
3.flexion
4.transeverse diffusion(flip-flop)

Question 8

fastest and slowest lipid diffusion

Answer 8

最快：lateral diffusion（最多出现）
最慢：transverse diffusion(最少出现

Question 9

膜中质量最大的成分

Answer 9

lipids最多 蛋白质其次 碳水最少

Question 10

Factors determine diffusion rate

Answer 10

1.temperature
2. Length of chains
3.degree of unsturation
4. Cholesterol concentration

Question 11

Degree of unsaturation and fluidity?

Answer 11

Ability to pack PACK
越不饱和越liudong

Question 12

cholesterol and fluidity at high temp

Answer 12

at high temp, cholesterol stops lipid movement, make lipid less fluid

Question 13

cholesterol and fluidity at low temp

Answer 13

at low temp, cholesterol stops lipid packing, make lipid more fluid

Question 14

Who anchors protein to membrane?

Answer 14

Lipid

Question 15

大部分穿膜蛋白是什么类型

Answer 15

α-helix

Question 16

how to identify sphingolipids?

Answer 16

amide bond酰胺

Question 17

why Bilayers are asymmetrical

Answer 17

Proteins * Lipid head groups * Carbohydrates * NOT cholesterol Enzymes maintain asymmetry(transverse diffusion)

Question 18

Functions of membrane proteins

Answer 18

1. Transporters and channels
2. Receptors
3. Enzymes
4. Anchors

Question 19

how is facilitated transport different from channels

Answer 19

Channels: open pathway, discriminating based on size and charge
Transporters: specific binding site, conformational changes during transpor

Question 20

Membrane proteins can diffuse in the bilayer unless restricted true or false

Answer 20

true

Question 21

what are Glycosphingolipids:

Answer 21

Glycosphingolipids: Head group contains a sugar

Question 22

Why do transmembrane regions of integral membrane proteins stay within the membrane?

Answer 22

Hydrophobic effect. The transmembrane regions contain hydrophobic side chains that would be exposed to water if they were to leave the membrane.

Question 23

The hydrocarbon chains of most fatty acids produced by humans:

Answer 23

Contain an even number of carbon atoms