Assertion (A): Replication of DNA takes place in S phase of the cell cycle.
Reason (R): DNA replication and cell division cycle should be highly coordinated.
Reason (R): DNA replication and cell division cycle should be highly coordinated.
Show Hint
- Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
- Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
- Assertion (A) is true, but Reason (R) is false.
- Assertion (A) is false, but Reason (R) is true.
The Correct Option is A
Solution and Explanation
Top Questions on Molecular Basis of Inheritance
- The RNA triplet UAG acts as a stop codon which terminates the synthesis of a polypeptide. Below is given a strand of DNA which codes for four amino acids.
In which position will an insertion of a thymine nucleotide result in the termination of translation?
DNA strand:
3′ T C C A C C C G A T G C 5′- CBSE CLASS XII - 2025
- Biology
- Molecular Basis of Inheritance
Construct and label a transcription unit from which the RNA segment given below has been transcribed. Write the complete name of the enzyme that transcribed this RNA.
- CBSE CLASS XII - 2025
- Biology
- Molecular Basis of Inheritance
- The base sequence in one of the strands of DNA is: ‘TAGCATGAT’
- Give the base sequence of its complementary strand.
- How are these base pairs held together in DNA molecule?
- Explain the base complementarity rule. Name the scientist who framed this rule.
- CBSE CLASS XII - 2025
- Biology
- Molecular Basis of Inheritance
Student to attempt either option-(A) or (B):
(A) Write the features a molecule should have to act as a genetic material. In the light of the above features, evaluate and justify the suitability of the molecule that is preferred as an ideal genetic material.
OR
(B) Differentiate between the following:- [(i)] Polygenic Inheritance and Pleiotropy
- [(ii)] Dominance, Codominance and Incomplete dominance
- CBSE CLASS XII - 2025
- Biology
- Molecular Basis of Inheritance
- A segment of DNA, ‘TTG AGG GGG ATG’ was translated into an oligopeptide with the amino acids, Lysine - Serine - Proline - Tyrosine.
- [(a)] Write the codons in correct sequence for the four amino acids.
- [(b)] If first adenine in DNA is substituted by guanine, what will be the sequence of amino acids in the new oligopeptide?
- [(c)] Write the anticodons for these amino acids.
- CBSE CLASS XII - 2025
- Biology
- Molecular Basis of Inheritance
Questions Asked in CBSE CLASS XII exam
(A) Explain the following reactions and write chemical equations involved:
(a) Wolff-Kishner reduction
(b) Etard reaction
(c) Cannizzaro reaction- CBSE CLASS XII - 2025
- Oxidation And Reduction Reactions
Inspired by the success of Chandrayaan-3, the Chief Scientist at ‘Space Rover’ a private research group, decided to send some innovative ideas regarding the mission to the Chief Scientist of Chandrayaan-3. The Chief Scientist at ‘Space Rover’ formed four groups for the same. As it was an intellectual activity of thinking rather than doing, these four groups started interacting with each other and friendships developed. On the basis of their interaction and friendship, some members from each group formed ‘Entertainment Through Reading’ group which showed conformity in terms of their interest. ‘Entertainment Through Reading’ group had no written rules, was unstable in form and scope and had no fixed lines of communication. The members of this group enhanced the morale of each other, enjoyed drinking coffee together, read books, served different issues of their work areas and provided support to each other. Ultimately this group developed some innovative ideas which were sent by ‘Space Rover’ to the Chief Scientist of Chandrayaan-3. Though this group was formed for recreation but it contributed towards fulfillment of organisational objectives.
(a) Identify the function of management. Quoting the lines from the above para, explain the steps of the process of the function of management discussed.
(b) Also explain any two points of importance of the function of management identified in (a).- CBSE CLASS XII - 2025
- Controlling
(a) Identify and explain the function of management discussed in the above para.
(b) Explain any four points of importance of the function identified in (a).- CBSE CLASS XII - 2025
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(i) Credit allowed
(ii) Production cycle
(iii) Availability of raw material- CBSE CLASS XII - 2025
- Financial Management and Financial Market
Explain the following points of significance of principles of management:
(i) Providing managers with useful insights into reality
(ii) Meeting changing environment requirements
(iii) Scientific decisions- CBSE CLASS XII - 2025
- Principles of Management