Molecules Of Functional Significance : Lipids

Question 1

1.) Lipids are defined as ____ ?

Answer 1

A heterogenous group of naturally occurring compounds which are relatively insoluble in water but freely solvable in nonpolar organic substances.

OR

Long chain hydrocarbon groups that may contain oxygen, phosphorous, nitrogen and sulfur

Question 2

2) List three functions of lipids.

Answer 2

Triglycerides are a major storage form of energy.
Form important constituents of the cell membrane.
Used for the synthesis of cholesterol.
Maintains membrane structure and integrity.
Aids in blood coagulation.

Question 3

3.) Which of the the following describes the functions of lipids?

A) aids in blood peptization.
B) forms important constituents of the mitochondria.
C) major storage form of energy.
D) maintains exoskeleton structure and integrity.

Answer 3

C) Major storage form of energy.

Question 4

4.) Fats and waxes belong to which class of lipids?

A) simple lipids
B) compound lipids
C) derived lipids
D) complex lipids

Answer 4

A) Simple lipids.

Question 5

5.) Which of the following accurately depict a triglycerol?

A) 	α1 CH2-OH
		| 
	β   CH-OH + 3 Fatty Acids 
		|
	α2 CH2-OH

B) α1 CH2-O-CO-R1
		| 
	β   CH-O-CO-R2
		|
	α2 CH2-O-CO-R3

C) CH2OH
		   |
	R”OOCH
	         |
	CH2OH

Answer 5

B) α1 CH2-O-CO-R1
		| 
	β   CH-O-CO-R2
		|
	α2 CH2-O-CO-R3

Question 6

6.) Which of the following is false?

A) The R groups indicate the fatty acids.
B) Each R group must be a different fatty acid type.
C) R2 is an unsaturated fatty acid.

Answer 6

B) Each R group must be a different fatty acid type is false because R groups 1 and 3 can either be the same or different fatty groups while R2 is typically an unsaturated fatty acid.

Question 7

7.) Compound lipids are____?

Answer 7

Esthers of fatty acids with one of the various alcohols and in addition it contains other non lipid components.

Question 8

8.) _____ contains alcohol, fatty acids, phosphoric acid and choline

A) Cephalines
B) Lecithin
C) Phosphatidyl ethanolamine
D) Phosphatidyl inositol.

Answer 8

B) Lecithin / Phosphatidyl choline

Question 9

9. ) Lecithin is present in which of the following?
   i) cardiac tissue, skin, spinal fluid.
   ii) bones, liver tissue, bone marrow.
   iii) brain, nervous tissue, sperm.

A) i and iii only.
B) i and ii only.
C) i , ii, and iii.
D) iii only.
E) ii and iii only

Answer 9

D) lecithin is present in the brain, nervous tissue, sperm and egg yolk

Question 10

10.) Dipalmitayl lecithin is a lung surfactant which ______.

Answer 10

Lowers surface tension and prevents the collapse of lung alveoli.

Question 11

11.) What produces respiratory distress syndrome/ hyaline membrane disease in premature infants?

Answer 11

An absence of dipalmitoyl lecithin

Question 12

12.) Cephalins contain_____ and are present in_____.

Answer 12

A basic phospholipid with ethanolamine as the nitrogenous base
The brain, erythrocytes and many other tissues.

Question 13

13.) Sphingomyelin is present in?

Answer 13

The brain, lungs and nerves

Question 14

14.) What is the Niemann-Pick disease?

Answer 14

A deficiency of sphingomyelinase in the liver, lymph nodes, bone marrow and central nervous system.

Question 15

15.) What is Gaucher’s disease?

Answer 15

An increased level of cerebrosides in tissues like the spleen, liver, lymph nodes and bone.

Question 16

16.) What disease is characterized by elevated ganglioside levels?

Answer 16

Tay-Sachs disease

Question 17

17.) Where are Very Low Density Lipoprotiens synthesized?

Answer 17

VLDL are synthesized in the liver and transport endogenous triglycerides from the liver to the extrahepatic tissues.

Question 18

18.) What are the most abundant phospholipids of the cell membrane?

Answer 18

Lecithins

Question 19

19.) A glycerol molecule which has one molecule of fatty acid is known as?

Answer 19

Monocylglycerol

Question 20

20.) Cephalins play a role in which of the following?

A) Apoptosis
B) Diffusion
C) Active Transport

Answer 20

A) Apoptosis i.e. cell death

Question 21

21.) Phosphatidyl inositol play an important role in?

A) Cell signaling and membrane trafficking for the cell membrane.
B) Translation and Transcription
C) Allowing materials in and out of the cell

Answer 21

A) Cell signaling and membrane trafficking for the cell membrane.

Question 22

22.) Why are saturated and trans-fat dangerous?

A) They can raise cholesterol level leading to increased risk of heart disease.
B) They can raise blood pressure leading to increased risk of heart disease.

Answer 22

They can raise cholesterol level leading to increased risk of heart disease.

Question 23

23.) Omega 3 & 6 benefits are:

A) Decreases risk of Alzheimer’s, help maintain a good mood.
B) Influences better mental health and help maintain a well balanced diet.

Answer 23

A) Decreases risk of Alzheimer’s, help maintain a good mood.

Question 24

24.) Which of the following is an important constituent of plasma membranes?

A) Steroids
B) Fatty Acids
C) Cholesterol

Answer 24

B) Fatty Acids