CUET · BIOLOGY · PYQ PAPER 2023

Which of the following is used to make the bacterial cell as 'Competent cell' to take up DNA?

A Carbonate ion
B Calcium ion
C Sodium ion
D Sulphate ion

Verified Solution

Answer & Solution

Correct Answer

(B) Calcium ion

Step-by-step Solution

Detailed explanation

Calcium ion

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.

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Identify the statements which are not true for the genetic code.
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LIST I LIST II
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LIST I LIST II
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Full form of ELISA is:

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Match List-l with List-II
List-l
(Product) List-II
(Producer)
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LIST I	LIST II
A. VI	I. Antipodals
B. III	II. Egg cell
C. IV	III. Filliform apparatus
D. I	IV. Central cell

LIST I	LIST II
A. Parthenocarpic fruits	I. Fruit develops from fertilised ovary
B. True fruit	II. Apple
C. Apomixis	III. Asteraceae
D. False fruit	IV. Fruit develops without fertilisation

List-l (Product)	List-II (Producer)
(A) Citric Acid	(I) Trichoderma polysporum
(B) Ethanol	(II) Monascus purpureus
(C) Statins	(III) Saccharomyces cerevisiae
(D) Cyclosporin A	(IV) Aspergillus niger