Biology · Chemistry

Carbohydrates and Biomolecules

1,073 Questions

Carbohydrates and biomolecules questions test your understanding of sugars, monosaccharides, and metabolic substrates. The topic covers food transportation in plants and the biochemical properties of sweeteners. Practicing these questions builds a strong foundation for exam preparation.

Disaccharides and monosaccharidesArtificial sweetenersGlycogen storagePlant food transportGlycoprotein hormones

Carbohydrates and Biomolecules Questions

Multiple choice

What is an invert sugar?

  1. An isomer of sucrose

  2. An equimolar mixture of glucose and fructose

  3. Fructose

  4. Racemic mixture

  5. None of these

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

 
 

Multiple choice

Which of the following sugar is present in nucleic acids?

  1. Pentose

  2. Hexose

  3. Fructose

  4. Glucose

  5. Sucrose
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Nucleic acids contain pentose sugars (5-carbon sugars). DNA contains deoxyribose and RNA contains ribose, both of which are pentose sugars, not hexose, fructose, or glucose.

Multiple choice

Which of the following statements is/are incorrect about phloretin?

  1. Phloretin is obtained from apple leaves.

  2. Phloretin inhibits the transportation of glucose into the cell by SGLT1 and SGLT2.

  3. Phloretin inhibits glucose transportation in large intestine.

  4. Phloretin inhibits urea transport.

  5. Both 1 and 2

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This option is correct.

Multiple choice

Maximum carbohydrate is present in:

  1. oryza sativa

  2. zea mays

  3. pisum sativum

  4. triticum vulgare
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Rice (Oryza sativa) grains are rich in starch, which is a carbohydrate polymer. Among the options given - rice, maize, pea, and wheat - rice has the highest starch content in its grains, which serve as the primary energy storage form. Cereal grains like rice are cultivated specifically for their high carbohydrate content.

Multiple choice

Which of the following is a pair of homopolysaccharides?

  1. Dextran and heparin

  2. Dextran and amylopectin

  3. Heparin and amylopectin

  4. Heparin and chondroitin-4-sulfate

  5. Chondroitin-4-sulfate and dextran
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Dextran is a complex, branched homopolysaccharide made of many glucose molecules. Amylopectin is homopolysaccharide of glucose.

Multiple choice

Glycosidic bond is broken during digestion of

  1. protein

  2. starch

  3. lipid

  4. All of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Glycosidic bonds are the covalent bonds linking sugar molecules in carbohydrates like starch. During carbohydrate digestion, enzymes break these glycosidic bonds to release simple sugars. Proteins and lipids have different bond types.

Multiple choice

Honey that has a high concentration of sugar, does not decay because

  1. it contains natural antioxidant that prevent bacterial attack

  2. bacteria cannot survive in an active state in a solution of high osmotic strength, as water is drawn out from honey

  3. in honey bacteria are totally deprived of oxygen

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Honey has a very high sugar concentration (about 80% sugars like fructose and glucose). This creates a solution with extremely high osmotic pressure. When bacteria are exposed to this, water is drawn out of the bacterial cells by osmosis, causing them to become dehydrated and die, preventing decay.

Multiple choice

Which of the following sweeteners does not provide any energy to the body?

  1. Glucose

  2. Fructose

  3. Maltose

  4. Saccharin
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Saccharin is an artificial sweetener that provides sweetness without calories because the human body cannot metabolize it. In contrast, glucose, fructose, and maltose are natural carbohydrates that provide approximately 4 calories per gram when metabolized by the body.

Multiple choice

Which one of the following structural components of cell wall of fruits is commercially valuable for the manufacture of food jellies?

  1. Cellulose

  2. Hemicellulose

  3. Lignin

  4. Pectin
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Pectin is a polysaccharide found in plant cell walls, especially in fruits. It has excellent gelling properties when heated with sugar and acid, making it ideal for making jellies and jams. Commercial pectin is extracted primarily from citrus peels and apple pomace.