Lipids

Question 1

This lipid is the major reserve energy in the body. (Our fat cells are filled with this too)

Answer 1

Triacylglycerols

Question 2

These lipids play a big role in the fluidity and flexibility of the membrane. Allows what goes in and out.

Answer 2

Phospholipids

Question 3

These lipids participate in lipid rafts, making localized areas in the membrane. Important for the structure of plasma membranes.

Answer 3

Sphingolipids

Question 4

This lipid maintains membrane permeability (dissolvability), maintains fluidity. Also a precursor of steroid hormones.

Answer 4

Cholesterol

Question 5

What are the fat soluble vitamins? And they are ______-based lipids.

Answer 5

A-D-E-K. Isoprene-based lipids

Question 6

True or False, fats/lipids act as electrical insulators?

Answer 6

True, example are myelin sheaths in our ervous system.

Question 7

Can lipids function as metabolic regulators or signaling molecules? If not why?

Answer 7

Yes they can.

Question 8

What are the 3 main types of lipids? And if you think there is 4, which is the last one?

Answer 8

Fatty acids Glycerolipids Sphingolipids Cholesterol

Question 9

This lipid has a long akyl chain with a carboxyl group at the end. (Double bond O-C-OH).

Answer 9

Fatty acids.

Question 10

1. They have a glycerol backbone with fatty acids. 2. If they have a fatty acid in the SN1, 2, and 3rd position then they are called? 3. If they have a fatty acid in the SN1, 2, BUT the 3rd position they have a head group base ex. PO4, alcohol (OH).

Answer 10

1. Glycerolipids 2. Triacylglycerol 3. Phospholipids

Question 11

Instead of the glycerol backbone, these have the sphingosine backbone, still has 3 carbons but a little more modified. With fatty acid in the sn2 position, and a base in the 3rd position.

Answer 11

Sphingolipids, Sphingomyelin

Question 12

Sphingosine backbone with fatty acid and sugar like (mono-or oligo saccharide). What is this?

Answer 12

Glycolipids

Question 13

Flexible akyl chain, rigid steroid nucleus, and hydroxyl group. What am I?

Answer 13

Cholesterol

Question 14

Carboxylic acids are nonpolar/polar? Hydrophilic/hydrophobic? Water soluble/insoluble? Fat soluble/insoluble? On a fatty acid are they the fatty or the acid? Lol.

Answer 14

POLAR HYDROPHILIC WATER SOLUBLE FAT INSOLUBLE ACID

Question 15

Tell me about them aliphatic tails. Short/long? Polar/nonpolar? Hydrophilic/hydrophobic? Saturated/unsaturated? Fat soluble/insoluble? Water soluble/insoluble? Fatty or acid? How long are their chains usually?

Answer 15

Long, nonpolar Hydrophobic, saturated AND unsaturated. Fat soluble Water insoluble FATTY. 2-28 carbons (even numbers mostly)

Question 16

Fatty acids with no double bonds are called what? Examples include Palmitic acid, Myristic acid, Lauric acid, Stearic acid.

Answer 16

SATURATED (NO BOND). Play important role in membrane fluidity.

Question 17

What happens to the structure of a fatty acid when it is saturated? Ad why is this role important?

Answer 17

When the fatty acid is saturated there are no double bonds (the carboxyl polar head group, and long aliphatic chain). When there is no double bonds, it is a very STRAIGHT structure. It plays an important role in membrane fluidity.

Question 18

Fatty acids with 1 double bond is called? Examples?

Answer 18

Unsaturated fatty acids. Ex: Monounsaturated, oleic acid. CIS double bond (makes the curve).

Question 19

Fatty acids with more than 1 double bond? Examples include ?

Answer 19

Polyunsaturated fatty acids. Linoleic acid, arachidonic acid (n-6). And Linolenic acid (n-3). CIS DOUBLE BOND makes the curve.

Question 20

Nomenclature x:y (triangle) a, b, c Tell me what each variable represents.

Answer 20

X= # of C’s in the chain Y= # of double bonds A,b,c = positions of the start of the double bonds, beginning from C1 - the carboxyl C. (You dont include the carboxyl end as a double bond)

Question 21

Nomenclature examples using systemic names IUPaC. Find the x:y triangle a,b,c. Hexadecanoic acid = OctadecEnoic acid = OctadecaTRIenoic acid =

Answer 21

Hexadecanoic = 16:0 saturated obviously since no double bond OctadecEnoic = 18:1 monounsaturated cis double bond curve Octadecatrienoic = 18:3 triangle 9, 12, 15 polyunsaturated cis double bond curve. (You dont include the carboxyl end as a double bond)

Question 22

Omega labeling system. Explain…. Also what would octadecatrienoic acid be in thi labeling system?

Answer 22

C’s are numbered from the distal end (called the n or (w) aka omega end) of an acyl chain (which is opposite of the carboxyl group). The 18:3 triangle 9,12,15 would now be 18:3 (w-3) or 18:3 (n-3). So if it is an 18 carbon in the systemic name, with 15 as its last double bond location, then that means in omega system, it’ll be 18:3 (w-3) or (n-3) since the first double bond will start at C3 while the terminal C in the systemic group will now be C1. (You dont include the carboxyl end as a double bond)

Question 23

Give me 2 examples of essential unsaturated fatty acids? (Hint one of them is omega 3). What is so good about being essential?

Answer 23

Linoleic acid (w6) 18:2 Alpha-linolenic acid (w3) 18:3 we can synthesize.

Question 24

Lipids with the glycerol backbone? Tell me what they are usually composed of? What are the 2 types, and what is the main role of each?

Answer 24

Glycerolipids composed of mono, di, and tri substituted glycerols. (Aka can be one, two, or three fatty acids with ester linkage SN1, SN2, SN3) Triglycerides TG is the storage form of ENERGY. Fa’s in SN1, SN2, SN3. Diglycerides DG acts as a SECOND MESSENGER. Fa’s are in the SN1 and SN2 positions, act as second messenger for protein kinase C (PKC).

Question 25

Glycerol backbone, Fatty acids sn1, sn2, and third position contains a phosphate or base head group (polar). What am I? What are they the precursors to? Significance of the sn1 and sn2 positions?

Answer 25

Phospholipid Precursors of signaling molecules. The fatty acid in the sn1 position is saturated. The fa in sn2 is unsaturated aka bent, cis double bond. The Fa’s are the hydrophobic regions

Question 26

Glycerol backbone, 2 saturated fatty acids, unsaturated fatty acid. What am I? What type of molecule am I? And what does that mean?

Answer 26

Phosphatidylcholine. Amphipathic meaning has hydrophilic and hydrophobic regions

Question 27

Contains both positive and negative charge. But is considered electrically neutral. Example?

Answer 27

Zwitterion Ex: phosphatidylcholine Which is a type of phospholipid. Important when it has to do with the non-covalent packing of the membranes.

Question 28

What could this be structurally? -CH2-CH—CH2-

Answer 28

Glycerol backbone

Question 29

What charge does the phosphate group have? And where is it usually located?

Answer 29

Negative charge. Usually located on a phospholipid along the hydrophilic head group.

Question 30

What can usually be attached at the X portion (which is at the end of the phosphate group that is attached to the glycerol backbone, but not on the negative O charge, it is on the normal O that does not have the double bond) aka hydrophilic head group of the phospholipid? (Name 6)

Answer 30

Many different types of bases. Phosphatidic acid, phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, and phosphatidylglycerol.

Question 31

If the phospholipid head group has this attachment, what is it? -H What charge will this have?

Answer 31

Phosphatidic acid. Negative charge. (Because the phosphate on the phospholipid is already negative)

Question 32

If the phospholipid head group has this attachment, what is it? -CH2-CH2-N+(CH3)3 (What group is this?) What charge will it be?

Answer 32

Phosphatidylcholine Choline group. Neutral charge zwitterion (the - phosphate with the positive N on the choline makes it electrically neutral)

Question 33

If the phospholipid head group has this attachment, what is it? -CH2-CH2-N+H3 (What group is this?) What charge will it be?

Answer 33

Phosphatidylethanolamine Adding an ethanolamine group. Neutral zwitterion, the - from phosphate head with the + from the nitrogen on the ethanolamine.

Question 34

If the phospholipid head group has this attachment, what is it? -COO- (What group is this?) What charge will it be?

Answer 34

Phosphatidylserine Serine group Will be negative overall since phosphate is -, then the NH3 is + on the amino group, and the other - on the carboxyl COO-. 2 negative and one positive = negative overall.

Question 35

If the phospholipid head group has this attachment, what is it? -OH-OH-OH-OH-OH- all chair formation (What group is this?) What charge will it be?

Answer 35

Phosphatidylinositol Linositol group. Will be - charge because of the phosphate head. But the linositol itself is normal.

Question 36

If the phospholipid head group has this attachment, what is it? -CH2-CHOH-CH2OH (What group is this?) What charge will it be?

Answer 36

Phosphatidylglycerol Glycerol group. Overall negative because of the only charge on phosphate head group.

Question 37

This molecule has a sphingosine backbone with a saturated fatty acid in the sn2 position. (What type of linkage?)

Answer 37

Sphingolipids (Bound to a nitrogen, the Fa in the sn2 position) = Amide linkage. (This is different to when you had the hydroxyl group for the glycerol backbone, and the fa was connected via ester linkage).

Question 38

Sphingosine backbone with fa in sn2 position via amide linkage, and the head group x is H. What is this?

Answer 38

Ceramide which is a type of sphingolipid.

Question 39

Sphingosine with sn2 fa amide linkage, and X group is phosphocholine attached to the terminal hydroxyl group by ______ bond? What is its significance?

Answer 39

ester bond. Sphingomyelin. Significance is in the formation of lipid rafts.

Question 40

Sphingosine backbone, sn2 fa w/ amide linka1ge. X group is CHO or carbohydrate.

Answer 40

Glycolipids Lipid containing sugars derived from sphingosine

Question 41

Sphingosine backbone, fa in sn1, fa in sn2 via amide linkage, and the X is glucose or galactose, aka sugar unit. What am I?

Answer 41

Cerebroside which is a glycolipid.

Question 42

Amphipathic hydrophobic flexible alkyl side chains Hydrophobic steroid rigid nucleus. (Does not bend/move three 6-ring, one 5-ring structures). Hydrophilic hydroxyl (OH) group at the head (which makes it polar). What am I? What is the importance of the hydroxyl hydrophilic polar head?

Answer 42

Cholesterol, a lipid. Hydrophilic polar heads allows it to circulate and get into the membranes (important function).

Question 43

What are the 3 negatively charged phospholipids?

Answer 43

PI and PG And PS Phosphatiylinositol and phosphatidylglycerol and phosphatidylserine.

Question 44

What are the zwitterions of phospholipids (2)?

Answer 44

PC and PE Phosphatidylcholine, and phosphatidylethanolamine.

Question 45

Phospholipid with 2 glycerols in the x.

Answer 45

DPG diphosphatidylglycerol also known as CARDIOLIPIN Has double negative charge.