CARBOHYDRATES

Question 1

What are carbohydrates?

Answer 1

Are organic compounds, polyhydroxy aldehyde or ketone or their derivatives on hydrolysis.

Question 2

2. How are carbohydrates classified?

Answer 2

Classification of Carbohydrates: Divided based on the number of sugar units—monosaccharides (1 unit), disaccharides (2 units), oligosaccharides (3-10 units), polysaccharides (many units)

Question 3

What is a monosaccharide?

Answer 3

Monosaccharide: Simplest carbohydrate; single sugar unit that cannot be further hydrolyzed (e.g., glucose, fructose).

Question 4

Describe the structure of glyceraldehyde

Answer 4

4. Glyceraldehyde: Simplest aldose; an intermediate in glycolysis and gluconeogenesis pathways.

Question 5

What is the significance of dihydroxyacetone?

Answer 5

5. Dihydroxyacetone: Simplest ketose; plays a role in lipid metabolism.

Question 6

Explain the function of erythrose in metabolism.

Answer 6

Erythrose: Tetrose sugar; involved in the pentose phosphate pathway, a pathway important for NADPH production.

Question 7

What role does ribose play in nucleic acids?

Answer 7

Ribose: Pentose sugar; a component of RNA, essential for genetic material and energy transfer in cells (ATP)

Question 8

Differentiate ribose from ribulose

Answer 8

Ribose vs. Ribulose: Ribose is an aldose (aldehyde group); ribulose is a ketose (ketone group).

Question 9

What is the importance of xylose?

Answer 9

Xylose: Pentose; a building block in plant cell walls and a precursor for certain biomolecules.

Question 10

Describe xylulose and its function

Answer 10

Xylulose: Involved in the pentose phosphate pathway, contributing to cellular metabolism

Question 11

What are the main functions of glucose in the body?

Answer 11

Glucose: Most important monosaccharide; main energy source for cells, especially the brain and red blood cells.

Question 12

How does galactose differ from glucose

Answer 12

Galactose: Hexose; found in milk (as part of lactose); converted to glucose in the liver

Question 13

Why is fructose considered a ketohexose?

Answer 13

Fructose: Ketohexose; found in fruits and honey; metabolized primarily by the liver.

Question 13

Describe the structure and function of mannose

Answer 13

Mannose: Hexose; important for glycoprotein synthesis, especially in immune system function.

Question 14

What is a disaccharide?

Answer 14

Disaccharide: Carbohydrates composed of two monosaccharides linked by a glycosidic bond (e.g., sucrose, lactose).

Question 15

List the three main disaccharides and their components

Answer 15

16. Main Disaccharides:

Maltose: Glucose + Glucose

Lactose: Glucose + Galactose

Sucrose: Glucose + Fructose

Question 16

What is a polysaccharide

Answer 16

Polysaccharide: Large carbohydrate molecules; long chains of monosaccharides (e.g., glycogen, starch).

Question 16

What is the phenomenon of inversion?

Answer 16

Inversion: Change in optical rotation, especially seen when sucrose (dextrorotatory) is hydrolyzed into glucose and fructose.

Question 16

Define oligosaccharides and their functions.

Answer 16

Oligosaccharides: Chains of 3-10 monosaccharides; function in cell recognition and signaling.

Question 17

What are glycogen’s primary functions?

Answer 17

Glycogen: Animal storage form of glucose; highly branched; found in liver and muscles.

Question 18

Compare glycogen and starch.

Answer 18

22. Glycogen vs. Starch:

Glycogen: Found in animals, highly branched.

Starch: Found in plants, moderately branched

Question 18

Explain the difference between homopolysaccharides and heteropolysaccharides

Answer 18

20. Homopolysaccharides vs. Heteropolysaccharides:

Homopolysaccharides: Only one type of monosaccharide (e.g., glycogen).

Heteropolysaccharides: More than one type of monosaccharide (e.g., hyaluronic acid).

Question 19

What are dextrins, and where are they found?

Answer 19

Dextrins: Short chains of glucose formed during starch breakdown; used in adhesives and as thickening agents.

Question 20

Describe the structure of dextrans

Answer 20

Dextrans: Branched glucose polymers; used in medicine as plasma expanders to treat blood loss.

Question 20

Why is cellulose important for plants?

Answer 20

Cellulose: Structural polysaccharide in plant cell walls; humans lack the enzyme to digest it