Carbohydrates Chemistry

Question 1

Give an example about deoxysugars

Answer 1

2-deoxyribose which is present in DNA

Question 2

Amino sugars enters in the formation of some carbohydrates molecules , give an example

Answer 2

Enters in the formation of GAGs , glycoproteins and glycolipids

Question 3

Give an example about amino sugars

Answer 3

Glucoseamine and galactosamine

Question 4

How occurs the formation of sugar alcohols

Answer 4

It is formed by reduction of monosaccharides

Question 5

Give an example about the reduction of monosaccharides which produce sugar alcohols

Answer 5

For example :- 
Glyceraldehyde  —> glycerol 
Ribose —> ribitol
Glucose —> sorbitol 
Fructose —> sorbitol 
Mannose —> mannitol

Question 6

Formation of sugar acids

Answer 6

Formed by oxidation of aldehyde group of monosaccharides

Question 7

Give an example about sugar acids which is formed by oxidation of aldehyde group of monosaccharides

Answer 7

• aldonic acid
• uronic acid — oxidation —> glucoronic acid
• L-ascorbic acid “ vitamin C “

Question 8

Vitamin C / L-ascorbic acid , it is formed at plants or humans ?

Answer 8

It is formed in plants from glucose ascorbic acid is not synthesized in humans

Question 9

There us type of sugar acids essential synthesis of GAGs ( Glycos , Amino , Glycans )

Answer 9

Glucuronic acid , it is essential for GAGs synthesis

Question 10

Give the monosaccharides derives

Answer 10

1 - sugar acids
2 - sugar alcohols
3 - amino sugars
4 - deoxy sugars

Question 11

Importance of monosaccharides

Answer 11

• glucose is the main sugar present in blood —> it is the source of energy to all body cells
• pentoses enter in the structure of nucleic acids —> ribose —-> RNA , deoxyribose —-> DNA
• galactose is a component of lactose —> lactose is milk sugar —> disaccharide = glucose + galactose
• monosaccharides derivatives enters in the structure of cells and tissue .

Question 12

Give an example about isomerism

Answer 12

• isomers
• aldo-keto isomers
• enantiomers
• epimers
• anomers

Question 13

What is the simplest ketose

Answer 13

• The simplest ketose is “ dihydroxyacetone “

- C3 H6 O3

Question 14

Give an example about ketoses/keto sugars except “ dihydroxyacetone “

Answer 14

• erythrulose —> tetroses —> C4 H8 O4
• ribulose and xylulose —> pentoses —> C5 H10 O5
• fructose —> hexoses —> C6 H12 O6

Question 15

What is the mother compound of ketose/ketosugars

Answer 15

The simplest one which is “ dihydroxyacetone “

Question 16

What is the mother compound of all aldoses

Answer 16

• The mother compound of all aldoses is the “ aldotriose “ - “ glyceraldehyde “
• C3 H6 O3

Question 17

There is type of isomerism between aldo sugars and keto sugars which is it ?

Answer 17

Occurs between glyceraldehyde and dihydroxyacetone and called “ aldo-keto-isomers “

Question 18

There is a type of isomerism occurs between aldo sugars what is it

Answer 18

Occurs between D - glyceraldehyde and L - glyceraldehyde and it called enantiomers

Question 19

What are the most important monosaccharides ?

Answer 19

Aldo sugars and keto sugars

Question 20

Give an examples about aldo sugars except “ glyceraldehyde “

Answer 20

• Erythrose —> tetroses —> C4 H8 O4
• ribose and xylose —> pentoses —> C5 H10 O5
• glucose , mannose and galactose —> hexoses —> C6 H12 O6

Question 21

The simplest carbohydrate sugar how much carbon contains ?

Answer 21

Contains 3 carbone atoms “ triose “ —> C3 H6 O3

Question 22

What is the simplest sugar

Answer 22

Monosaccharide sugar

Question 23

The monosaccharides are classified by two methods what they are ?

Answer 23

• Classified according to number of carbon —> for example —> hexoses “ 6 carbons “
• classified according to functional groups —> for example —> ketone group —> ketoses .

Question 24

Classification of carbohydrates

Answer 24

• Carbohydrates are classified according to the hydrolysis products into :-
• monosaccharides —> contains one sugar units
• disaccharide —> contains two sugar units
• oligosaccharides —> contain from three to ten sugar units
• polysaccharides —> contain more than ten sugar units