Bimolecules

Question 1

Differentiate between butter and margrine

Answer 1

Butter has 80% fats while margarine has 80% vegetable oil
Butter is higher in cholesterol while margarine is lower in cholesterol
Butter has 50% saturated fat while margarine has 20% saturated fat

Question 2

Heteroglycans appear in 3 types of glycoconjugates . They are ________________, _______________ and ____________________

Answer 2

Proteoglycans
Peptidoglycans
Glycoproteins

Question 3

Mention one example each of disaccharide, triasaccharide, tetrasaccharide and pentasaccharide

Answer 3

Disaccgaride:e.g Maltose, lactose, sucrose
Trisaccharide:e.g Raffinose, maltrise
Tetrasaccharide: e.g stachyose
Pentasaccharide: e.g Fos ( inulin)

Question 4

Explain the formation of reducing and non reducing sugars. Illustrate with one example each

Answer 4

Reducing sugars are formed by the combination of an anemeric carbon of one sugar with a hydroxyl group of another one thus having s free anomeric carbon which makes it a reducing sugar e.g maltose, lactose etc

                                    WHILE Non reducing sugars are formed by the combination of the anomeric carbon of two sugars thus having no anomeric carbon making them non reducing sugars e.g sucrose, raffinose, etc

Question 5

What are derived sugars?

Answer 5

Derived sugars are sugar derived by reactions and modifications of their parent monosaccharides.

Question 6

Types of derived sugars

Answer 6

√Deoxy sugars
√Amino sugars
√Sugar alcohol
√Sugar acids
√Sugar phosphates

Question 7

Cellulose

Answer 7

Human and other mammals can metabolize, starch, glycogen, lactose and sucrose.

Mammals cannot metabolize cellulose because they have they lack enzymes capable of catalyzing the hydrolysis of ß-glycosidic linkages.

Ruminants such as cows and sheep have microorganisms in their rumen that produce ã-glycosidase, which enable them to obtain glucose from grass and plants rich in cellulose

Termites can also obtaine glucose from dietary cellulose because they have cellulose producing bacteria in their digestive tracts

Question 8

What is a REDUCING END?

Answer 8

A reducing end is the end of the polysaccharide with an anomeric cl not involved in a glycosidic bond

Question 9

Describe this disaccharide:

Maltose

Answer 9

This is a cleavage product of starch

Question 10

Disaccharide: Cellulose:

Answer 10

This is a product of the breaking of cellulose

Question 11

Sucrose

Answer 11

A common table sugar

Question 12

Lactose

Answer 12

Milk sugar composed of galactose and glucose

Question 13

Amylose

Answer 13

A glucose polymer

ã(1-4)

Question 14

What are lipids?

Answer 14

Lipids are heterogeneous group of compounds including fats, steroids, waxes etc

Question 15

Biological importance of lipids

Answer 15

√important dietary constituents because of their high energy value, fat soluble vitamins and essential fatty acids
√fat is stored in adipose tissue which served as thermal insulator in subcutaneous tissues in organs
√non polar lipids act as electrical insulators
√help in the synthesis of hormones

Question 16

Classify lipids based on saponification, biological functions and structural complexity

Classification based on saponificaton:

Answer 16

Saponifiable lipids: lipids with esters e.g triglycerides

Non saponifiable lipids: lipids without esters e.g prostagladin and cholesterol

Question 17

Classification of lipids based on biological functions:

Answer 17

Storage lipids: lipids used as stored form of energy in living organisms e.g tricylglycerol
Structural lipids: lipids found in the membranes of organisms e.g phospholipids and glycolipids

Question 18

Classification of lipids based on structural complexity

Answer 18

Simple lipids: Esters of fatty acids with various alcohols

Complex lipids: Esters of fatty acids with an alcohol and a phosphoric acid residue

Question 19

Distinguish between essential and non essential fatty acids

Answer 19

ESSENTIAL FATTY ACIDS are poly unsaturated fatty acids that cannot be produced by the body but gotten from dietary sources e.g. linoleic acid
WHILE
NON- ESSENTIAL FATTY ACIDS are produced adequately by the body e.g palmitic acid, steric acid etc

Question 20

Triglycerol:

Answer 20

The simplest lipids from fatty acids

Question 21

Saponificaton

Answer 21

Saponificaton is the alkali hydrolysis of fatty acids

Question 22

Saponificaton value

Answer 22

This is the number of milligram of KOH required to saponify 1g of fat

Question 23

Iodine number

Answer 23

Iodine number is the measure of the extent of unsaturation of fat equal to the number taken up by 100g of fat

Question 24

Some physical properties of fatty acids are determined by the______________

Answer 24

Chain length and degree of unsaturation

Question 25

Monounsaturated fatty acids have

Answer 25

One double bond

Question 26

Monounsaturated fatty acids have

Answer 26

One double bond

Question 27

Polyunsaturated fatty acids have

Answer 27

2 or more double bonds

Question 28

Eicosanoids are …

Answer 28

Compounds derived from eicosa (20 carbon) polyenoic fatty acids