Download App

Molecular Basis of Inheritance — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYMolecular Basis of Inheritance1 Mark
MCQ
For question, two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: Adenine and guanine are double $-$ ring bases.
Reason: Adenine and guanine are pyrimidines.
  • A
    Both assertion and reason are true, and reason is the correct explanation of assertion.
  • B
    Both assertion and reason are true, but reason is not the correct explanation of assertion.
  • ✓
    Assertion is true, but reason is false.
  • D
    Both assertion and reason are false.
✓

Answer

Correct option: C.
Assertion is true, but reason is false.
The bases of nucleic acids are of two types, $(i)$ pyrimidines and $(ii)$ purines. Adenine and guanine are double$-$ring bases called purines cytosine, thymine and uracil are single $-$ ring bases called pyrimidines

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "Assertion (A) & Reason (B) MCQ" from Molecular Basis of Inheritance→Molecular Basis of Inheritance — all question types→BIOLOGY STD 12 Science question papers→Maharashtra Board STD 12 Science question papers→Maharashtra Board question paper generator→

Similar questions

For question, two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion : Subsequent encounter with the same pathogen elicits a highly intensified anamnestic response.
Reason: This is based on the fact that our body appears to have memory of the first encounter.
→
For question, two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: Core enzyme catalyses chain elongation of $\text{RNA}.$
Reason: The presence of sigma factor is required for initiation of transcription.
→
For question two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: In some Drosophila, bilateral gynandromorphs are found.
Reason: The gynandromorphs are formed by an irregularity in mitosis at the first cleavage of the zygote.
→
For question, two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion : There is no chance of transmission of malaria to man on the bite of a male Anopheles mosquito.
Reason: It carries a non$-$virulent strain of Plasmodium.
→
For question two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion : Skin forms the first tine of defence.
Reason: It is a non$-$specific defence.
→
For question two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion : Test cross is a back cross.
Reason: In test cross, individual is crossed with recessive paren.
→
Two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: Whisky develops colour during the aging process.
Reason: Vodka is colourless.
→
For question two statements are given $-$ one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c) $ and $(d)$ as given below.
Assertion : Generally the intraspecific competition is more intense than interspecific competition.
Reason : lntraspecific competition occurs when the resources are in short supply.
→
For two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: Megaspore mother cell undergoes meiotic division.
Reason: All four megaspores form female gametophyte.
→
For two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: Nucellus functions as a nutritive tissue.
Reason: Nucellus is always exhausted completely during development of embryo sac.
→