Lipids

Question 1

What are the hydrophobic properties of lipids due to?

Answer 1

the long fatty acid chains

Question 2

What does it mean when a fatty acid is said to be unsaturated?

Answer 2

It means that it contains double bonds so it is not saturated with hydrogens

Question 3

What are the the nomenclature rules for fatty acids?

Answer 3

Fatty acid with no double bonds: -anoic
fatty acid with one double bond: -enoic
fatty acid with two double bonds: -adienoic
fatty acid with three double bonds: -atrienoic

Question 4

What are carbons 2 and 3 of the fatty acid carbon chain known as?

Answer 4

alpha and beta

Question 5

What is the methyl carbon atom at the distal end of the fatty acid chain known as?

Answer 5

omega carbon

Question 6

What is the configuration of double bonds in most unsaturated fatty acids, cis or trans?

Answer 6

cis

Question 7

Which would have a which of these would have the lowest melting point and why?

14: 2
14: 3
14: 1
14: 0

Answer 7

The 14:3 would have the lowest melting point because it contains the most double bonds 14:0 would have the highest melting point

Question 8

Which would have the highest melting point and why?

20: 0
24: 0
14: 0
18: 0

Answer 8

the highest melting points would be the 24:0 fatty acid because melting pints of saturated fatty acids increases with the chain length

Question 9

What are the abbreviations for the names of carbon chains of 12, 14, 16, 18, 20, 22, 24?

Answer 9

12= dodec-
14= tetradec-
16= hexadec-
18= octadec-
20= eicosa-
22= docos-
24= tetracos-

Question 10

What are the 4 components that make up a phospholipid molecule?

Answer 10

1. fatty acid
2. a backbone to which fatty acids are attached (glycerol or sphingosine)
3. a phosphate
4. an alcohol attached to phosphate

Question 11

What types of fatty acids usually occur at the C1 position and the C2 position of the glycerol?
Saturated or Unsaturated

Answer 11

C1= saturated usually C16 or C18
C2= unsaturated usually see lengths from C16 to C20

Question 12

T or F, lipids are water soluble?

Answer 12

False, they are highly soluble in organic solvents

Question 13

If you were having trouble with your memory and cognition a problem with which of these could be a contributing factor? 
A. Phosphatidylinositol
B. Phosphatidylcholine
C. phosphatidylserine
D. Diphosphatidylglycerol
E. Phosphatidylethanolamine

Answer 13

C. phosphatidylserine

Question 14

Which phosphoglyceride is a constituent of your cell membrane and pulmonary surfactant?

A. Phosphatidylethanolamine
B. Phosphatidylserine
C. phosphatidylinositol
D. phosphatidylcholine
E. Diphosphatidylglycerol

Answer 14

D. phosphatidylcholine

Question 15

What phosphoglyceride is found particulary in nervous tissue and composes 25% of all phospholipids

A. Phosphatidylethanolamine
B. Phosphatidylserine
C. phosphatidylinositol
D. phosphatidylcholine
E. Diphosphatidylglycerol

Answer 15

A. Phosphatidylethanolamine

Question 16

Which phosphoglyceride is an important component of the inner membrane of the mitochondrial?

A. Phosphatidylethanolamine
B. Phosphatidylserine
C. phosphatidylinositol
D. phosphatidylcholine
E. Diphosphatidylglycerol

Answer 16

E. Diphosphatidylglycerol

Question 17

What type of bond links fatty acid chains to the sphingosine backbone?

Answer 17

amide bond

Question 18

With respect to the sugar residue how are glycolipids oriented in the membrane?

With the sugar on the intracellular side
With the sugar on the extracellular side
with the sugar in the middle
None of the above are true

Answer 18

B. With the sugar on the extracellular side

Question 19

What is the simplest glycolipid and what are the two sugars that could be the single sugar residue?

Answer 19

cerebroside, glucose or galactose

Question 20

T or F, A complex glycolipid can contain up to 7 sugar residues branched off it.

Answer 20

True

Question 21

T or F, Cholesterol is found in all prokaryotes and eukaryotes.

Answer 21

F. it is not found in most prokaryotes

Question 22

T or F, Cholesterol is arranged equally in both the extracellular side and intracellular side of the membrane?

Answer 22

True