ACTIVITY 7

Question 1

• are heterogeneous group of naturally occurring substances.

Answer 1

lipids

Question 2

Lipids are characterized by their

Answer 2

insolubility in water and their solubility in nonpolar solvents such as
- ether, chloroform, benzene, hot alcohol

Question 3

lipids are important dietary constituents not only because of their high energy value but also because of the ____________ and ___________ contained in the fat of natural foods

Answer 3

fat-soluble vitamins and essential fatty acids

Question 4

In the body, ____
- serves as an efficient source of energy, both direct and potentially, when stored in adipose tissue
- serves as thermal insulator in the subcutaneous tissues and around certain organisms

Answer 4

fat

Question 5

_______ set as electrical insulators allowing rapid propagation of depolarization waves along myelinated nerves.

Answer 5

nonpolar lipids

Question 6

the fat content of _____ tissue is particularly high.

Answer 6

nerve tissue

Question 7

are important cellular constituents occurring both in the cell membrane and in the mitochondria within the cytoplasm, and serving also as a means of transporting lipids in the blood

Answer 7

lipoproteins (combinations of fat and proteins)

Question 8

classification of lipids depending on their structures

Answer 8

1. Simple lipids
2. Compound lipids
3. Derived lipids

Question 9

are esters of fatty acids with various alcohols which include
- triacylglycerols or triglycerides
- and waxes

examples: olive oil (plant derived triglyceride) and cod-liver oil (animal derived triglyceride)

Answer 9

simple lipids

Question 10

are esters of fat ty acids with alcohol plus other groups (phosphate, carbohydrate, and nitrogenous component)
- phospholipids
- glycolipids
- lipoproteins and proteolipids

Answer 10

compound lipids

Question 11

refer to derivatives obtained by hydrolysis of simple and compound lipids as long as they still possess the general physical characteristics of lipids.
- saturated fatty acids
- unsaturated fatty acids
- mono and diglycerides
- steroids
- other related compounds: bile acids and bile salts, carotenoids, tocopherols

Answer 11

derived lipids

Question 12

How to determine if the fatty acid is saturated or unsaturated?

Answer 12

Unsaturated fatty acids reacts with halogens such as BROMINE causing decolorization via addition to double bonds.

Question 13

The relative unsaturation can be determined by ________ by a definite amount of a sample lipid.

Answer 13

measuring the amount of halogen

Question 14

the presence of glycerol grouping as in coconut oil can be detected by means of the _________ test.

Answer 14

Acrolein test.

Question 15

In acrolein test, the ______ is oxidized by heating with a dehydrating agent.

Answer 15

glycerol group

Question 16

the unsaturated aldehyde, _______, is formed which has a characteristic acid, irritating odor.

Answer 16

acrolein

Question 17

test used to differentiate fats and oils from waxes

Answer 17

acrolein test since waxes do not contain the glycerol grouping

Question 18

Cholesterol gives characteristics colored condensation products with ______ and ________.

Answer 18

Acetic anhydride and concentrated sulfuric acid

Question 19

test used to determine the presence of cholesterol

Answer 19

Lieberman-Burchard reaction

Question 20

positive result of Lieberman-Burchard reaction yields a _______ (color) solution. This is the basis for a number of quantitative determination of Cholesterol.

Answer 20

deep blue green solution

Question 21

Vitamin A is detected by ________ reaction

Answer 21

Carr-Price reaction

Question 22

Carr-Price reaction involves a series of color changes until finally a _____ (color) solution is obtained

Answer 22

pink solution

Question 23

is used to determine tocopherols (vitamin E) in foodstuffs

Answer 23

Furter-Meyer test

Question 24

in Furter-Meyer test, the _______ color is specific for tocopherols.

Answer 24

bronze-red color

Question 25

in Furter-Meyer test, Carotenoids and certain sterols produce a _______ color and when present in sufficient quantity may mask the bronze-red color of small amounts of tocopherols

Answer 25

yellow or brown color

Question 26

Lipids are _______ in H2O, dilute NaOH, Dilute HCl, Cold C2H5OH

Answer 26

insoluble

Question 27

Lipids are ______ in hot C2H5OH, CHCl3, Ether, Methylene chloride, CCl4

Answer 27

soluble

Question 28

rank the degree of unsaturation (olive oil, peanut oil, corn oil, coconut oil)

Answer 28

1- coconut oil 2- peanut oil 3- corn oil 4- olive oil

Question 29

Modified Furter-Meyer Test< Color reaction of vitamin E with n-butyl alcohol

Answer 29

bronze red

Question 30

Lieberman-Burchard Reaction , Color reaction of Cholesterol with acetic anhydride

Answer 30

deep-blue green

Question 31

Salkowski test (orH2SO4Test), Color reaction of Cholesterol with H2SO4:

Answer 31

red

Question 32

Based on your experiment, enumerate the best solvents for lipids

Answer 32

HOt alcohol, choloroform, ether, methylene chloride

Question 33

Othername of acrolein

Answer 33

propenal

Question 34

a group of compounds which contributes to the keeping quality of fats

Answer 34

antioxidants