Cellulose does not form blue colour with lodine because

NEET-2023 [Biomolecules] [class-xi ]

• It breakes down when iodine reacts with it.
• It is a disaccharide.
• It is a helical molecule.
• It does not contain complex helices and hence cannot hold iodine molecules.
Correct Option: D  [ It does not contain complex helices and hence cannot hold iodine molecules. ]

Remark:

Melonate inhibits the growth of pathogenic bacteria by inhibiting the activity of:

NEET-2023 [Biomolecules] [class-xi ]

• Dinitrogenase
• succinic dehydrogenase
• Amylase
• Lipase
Correct Option: B  [ succinic dehydrogenase ]

Remark:

Given below are two statements:
Statement I: Low temperature preserves the enzyme in a temporarily inactive state whereas high temperature destroys enzymatic activity because proteins are denatured by heat. Statement II: When the inhibitor closely resembles the substrate in its molecular structure and inhibits the activity of the enzyme, it is known as competitive inhibitor.
In the light of the above statements, choose the correct answer from the options given below:

NEET-2023 [Biomolecules] [class-xi ]

• Statement I is false but statement II is true.
• Both Statement I and Statement II are true.
• Both Statement I and Statement II are false.
• Statement I is true but Statement II is false.
Correct Option: B  [ Both Statement I and Statement II are true. ]

Remark:

Given below are two statements:
Statement I: A protein is imagined as a line, the left end represented by first amino acid (C-terminal) and the right end represented by last amino acid (N-terminal)
Statement II: Adult human haemoglobin, consists of 4 subunits (two subunits of α type and two subunits of β type.)
In the light of the above statements, choose the correct answer from the options given below:

NEET-2023 [Biomolecules] [class-xi ]

• Statement I is false but Statement II is true.
• Both Statement I and Statement II are true.
• Both Statement I and Statement II are false.
• Statement I is true but Statement II is false.
Correct Option: A  [ Statement I is false but Statement II is true. ]

Remark:

Exoskeleton of arthropods is composed of :

NEET-2022 [Biomolecules] [class-xi ]

• Cutin
• Cellulose
• Chitin
• Glucosamine
Correct Option: C  [ Chitin ]

Remark:

Read the following statements on lipids and find out correct set of statements:
A. Lecithin found in the plasma membrane is a glycolipid
B. Saturated fatty acids possess one or more c = c bonds
C. Gingely oil has lower melting point, hence remains as oil in winter
D. Lipids are generally insoluble in water but soluble in some organic solvents
E. When fatty acid is esterified with glycerol, monoglycerides are formed
Choose the correct answer from the option given below:

NEET-2022 [Biomolecules] [class-xi ]

• A, B and C only
• A, D and E only
• C, D and E only
• A, B and D only
Correct Option: C  [ C, D and E only ]

Remark:

A dehydration reaction links two glucose molecules to produce maltose. If the formula for glucose is C6H12O6 then what is the formula for maltose ?

NEET-2022 [Biomolecules] [class-xi ]

• C₁₂H₂₄O₁₂
• C₁₂H₂₂O₁₁
• C₁₂H₂₄O₁₁
• C₁₂H₂₀O₁₀
Correct Option: B  [ C₁₂H₂₂O₁₁ ]

Remark:

Match List-I with List-II.

NEET-2022 [Biomolecules] [class-xi ]

• A-IV, B-II, C-I, D-III
• A-II, B-IV, C-III, D-I
• A-IV, B-III, C-I, D-II
• A-III, B-II, C-IV, D-I
Correct Option: C  [ A-IV, B-III, C-I, D-II ]

Remark:

Which of the following are not secondary metabolites in plants?

NEET-2021 [Biomolecules] [class-xi ]

• Morphine, codeine
• Amino acids, glucose
• Vinblastin, curcumin
• Rubber, gums
Correct Option: B  [ Amino acids, glucose ]

Remark:

Match List-I with List-II.

NEET-2021 [Biomolecules] [class-xi ]

• A-I, B-IV, C-III, D-II
• A-II, B-I, C-IV, D-III
• A-IV, B-III, C-I, D-II
• A-IV, B-I, C-II, D-III
Correct Option: D  [ A-IV, B-I, C-II, D-III ]

Remark: