21.

Which one out of (a) to (d) given below correctly represents the structural formula of the basic amino acid?

• 

• 

• 

• 

Given below is a schematic break-up of the phases/stages of cell cycle. Which one of the following is the correct indication of the stage/ phase in the cell cycle?

• C-karyokinesis

• S-synthetic phase

• A-cytokinesis

• B-metaphase

Which one of the following structural formula of two organic compounds is correctly identified along with its related function?

• B-uracil – a component of DNA

• A-triglyceride – major source of energy

• A-lecithin – a component of cell membrane

• B-adenine – a nucleotide that makes up nucleic

In photosynthesis carbon dioxide is converted to carbohydrates. It is a process.

• Reductive

• Oxidative

• Catabolic and exergonic

• None of the above

Which of the following is not an auxin?

• IM

• IBA

• Zeatin

• NM

Which of the following properties is shown by cytokinins?

• Delay leaf senescence

• Cause leaf abscission

• Promote seed dormancy

• Promote stornatal closing

Which of the following characteristics is are exhibited by C₄ -plants?

I. Kranz anatomy.
II. The first product of photosynthesis is oxaloacetic acid.
III. Both PEP carboxylates and ribulose biphosphate carboxylate act as carboxylating enzymes.

The correct option is

• I and III, but not ll

• I and II, but not III

• II and III, but not I

• ll and III

Which of the following plant keeps its stomata open during night and closed during the day?

• Orchid

• Cactus

• Tea

• Wheat

Genetic dwarfism can be overcome by

• Gibberellin

• Ethylene

• Auxin

• ABA

Hormone inducing fruit ripening is

• Cytokinin

• Ethylene

• Aabscissic acid

• Gibberellic acid