Tag: biomolecules

Questions Related to biomolecules

In fructose and glucose the possible optical isomers are:

  1. 12, 12

  2. 8, 16

  3. 16, 8

  4. 4, 12


Correct Option: B
Explanation:
Fructose contains three chiral carbon atom and glucose contain 4 chiral carbon atoms.
The Number of possible Optical isomers for Fructose are ${2}^{3} = 8$
The Number of possible Optical isomers for Glucose are ${2}^{4} = 16$
8, 16 is the Answer

The $\alpha$- D glucose and $\beta$- D glucose differ from each other due to difference in carbon atom with respect to its

  1. Number of $OH$ groups

  2. Size of hemiacetal ring

  3. Conformation

  4. Configuration


Correct Option: D

What is the nature of glucose-glucose linkage in starch that males its so susceptible to acid hydrolysis?

  1. Starch is hemiacetal

  2. Starch is acetal

  3. Starch is polymer

  4. Starch contain only few molecules of glucose


Correct Option: B

Rate of reaction depends upon_________?

  1. Temperature

  2. Catalyst

  3. Concentration

  4. All of these


Correct Option: D

Number of $HIO _4$ molecule required to complete oxidation one mole of glucose is :

  1. 4

  2. 5

  3. 6

  4. None of these


Correct Option: A

${ C } _{ 12 }{ H } _{ 22 }{ O } _{ 11 }\longrightarrow 12C+{ 11H } _{ 2 }{ O }$ in presence of concentrated ${ H } _{ 2 }{ SO } _{ 4 }$.

Which of the following is obtained in the above reaction?

  1. Animal charcoal

  2. Sugar charcoal

  3. Coke

  4. Wood charcoal


Correct Option: B

Which of the following does not reduce Benedict's solution?

  1. Sucrose

  2. Aldehyde

  3. Glucose

  4. Fructose


Correct Option: A
Explanation:
 Sucrose.. 
Because Sucrose (table sugar) contains two sugars (fructose and glucose) joined by their glycosidic bond in such a way as to prevent the glucose isomerizing to aldehyde, or the fructose to alpha-hydroxy-ketone form. Sucrose is thus a non-reducing sugar which does not react with Benedict's reagent.

In plant glycolipids, the sugar is normally.

  1. oil

  2. wax

  3. glycolipid

  4. phospholipid


Correct Option: C
Explanation:

Glycolipids yeild fatty acids, glycerol and carbohydrates on hydrolysis. Monogalactosyldiglycerides are glycolipids which are commonly found in plant leaves and algae. They contain a high proportion of poly unsaturated fatty acids and appear to play a role in photosynthesis.

Which of the following is/are correctly matched?

  1. D-Glucose & L-Galactose -Epimer

  2. Fructose & Mannose - Fundamental isomers

  3. D-Glucose & D-Mannose & Diatereomers

  4. $\alpha$-D-Glucopyranose & $\beta-D-Glucopytranose-Anomers


Correct Option: A

Carbohydrates may be:

  1. sugars

  2. starch

  3. polyhydroxy aldehyde/ketones

  4. compounds that can be hydrolyzed to sugar


Correct Option: A,B,C,D
Explanation:

Carbohydrates are primarily produced by plants and form a very large group of naturally occurring organic compounds. Some common examples are cane sugar, glucose, starch, etc.
T
he carbohydrates may be defined as optically active polyhydroxy aldehydes or ketones or the compounds which produce such units on hydrolysis.