Which of the following pair of organelles does not contain DNA:

NEET-2019 cell-the-unit-of-life [class-xi ]

• Mitochondria and Lysosomes
• Chloroplast and Vacuoles
• Nuclear envelope and Mitochondria
• Lysosomes and Vacuoles
Correct Option: D  [ Lysosomes and Vacuoles ]

Remark:

The shorter and longer arms of a submetacentric chromosome are referred to as:

NEET-2019 cell-the-unit-of-life [class-xi ]

• p-arm and q-arm respectively
• s-arm and l-arm respectively
• q-arm and p-arm respectively
• m-arm and n-arm respectively
Correct Option: A  [ p-arm and q-arm respectively ]

Remark:

Which of the following statements regarding mitochondria is incorrect?

NEET-2019 cell-the-unit-of-life [class-xi ]

• Mitochondrial matrix contains single circular DNA molecule and ribosomes.
• Inner membrane is convoluted with infoldings.
• Enzymes of electron transport are embedded in outer membrane.
• Outer membrane is permeable to monomers of carbohydrates fats and proteins.
Correct Option: C  [ Enzymes of electron transport are embedded in outer membrane. ]

Remark:

DNA precipitation out of a mixture of biomolecules can be achieved by treatment with:

NEET-2019 Biomolecules [class-xi ]

• Chilled ethanol
• Isopropanol
• Methanol at room temperature
• Chilled chloroform
Correct Option: A  [ Chilled ethanol ]

Remark:

Which of the following is a commercial blood cholesterol lowering agent?

NEET-2019 Biomolecules [class-xi ]

• statin
• Lipases
• Streptokinase
• Cyclosporin A
Correct Option: A  [ statin ]

Remark:

Consider the following statements:
(A) Coenzyme or metal ion that is tightly bound to enzyme protein is called prosthetic group.
(B) A complete catalytic active enzyme with its bound prosthetic group is called apoenzyme.
Select the correct option.

NEET-2019 Biomolecules [class-xi ]

• Both (A) and (B) are true.
• (A) is true and (B) is false.
• Both (A) and (B) are false.
• (A) is false and (B) is true.
Correct Option: B  [ (A) is true and (B) is false. ]

Remark:

Cells in G0 phase:

NEET-2019 Cell-Cycle-and-Cell-Division [class-xi ]

• enter the cell cycle
• suspend the cell cycle
• terminate the cell cycle
• exit the cell cycle
Correct Option: D  [ exit the cell cycle ]

Remark:

The correct sequence of phases of cell cycle is:

NEET-2019 Cell-Cycle-and-Cell-Division [class-xi ]

• G₁→ S→ G₂ → M
• M→ G₁→ G₂→ S
• G₁→ G₂→ S→ M
• S→ G₁→ G₂→ M
Correct Option: A  [ G₁→ S→ G₂ → M ]

Remark:

Xylem translocates:

NEET-2019 Transport-in-Plants [class-xi ]

• Water only
• Water and mineral salts only
• Water, mineral salts and some organic nitrogen only
• Water, mineral salts, some organic nitrogen and hormones
Correct Option: D  [ Water, mineral salts, some organic nitrogen and hormones ]

Remark:

Grass leaves curl inwards during very dry weather. Select the most appropriate reason from the following:

NEET-2019 Transport-in-Plants [class-xi ]

• Flaccidity of bulliform cells
• Closure of stomata
• Shrinkage of air spaces in spongy mesophyll
• Tyloses in vessels
Correct Option: A  [ Flaccidity of bulliform cells ]

Remark: