Plus Two Biology Previous Year Questions and Answers Pdf - 1

Question: 1

Identify the synthetic gene from the given genes sequence of a chromosome G-H-I-J-K-L-M-A-B

(A) A and B

(B) G and B

(C) J, K and L

(D) G and H

Question: 2

Transition type of gene mutation is caused when

(A) TC is replaced by AG

(B) AC is replaced by TG

(C) AG is replaced by TC

(D) AC is replaced by GT

Question: 3

Statement 1: Pairing of homologous chromosome is called as syndesis.
Statement 2: Proterminal synapsis occurs from telomeres.

(A) Statement 1 is correct and Statement 2 is incorrect

(B) Statement 1 is incorrect and Statement 2 is correct

(C) Both the statements are correct

(D) Both the statements are incorrect

Question: 4

Assertion (A): Complete linkage is noticed in male species of Drosophila.
Reason (R): Completely linked genes show some crossing over.

(A) A is true R is false

(B) Both A and R are false

(C) A is true, R is not correct explanation for A

(D) R explains A

Question: 5

Sharbati Sonara is a mutant wheat variety which is developed by irradiating the seeds with

(A) UV radiations

(B) X-rays

(C) Thermal neutrons

(D) Gamma radiation