In CBSE Class 10 Science Paper, Students will have to answer some questions based on Assertion and Reason. There will be a few questions based on case studies and passage based as well. In that, a paragraph will be given, and then the MCQ questions based on it will be asked.
Here, we have provided case based/passage based questions for Class 10 Science Chapter 9 Heredity and Evolution.
Case Study/Passage Based Questions
Question 1:
Read the following and answer any four questions from (i) to (v).
Pea plants can have smooth seeds or wrinkled seeds. One of the phenotypes is completely dominant over the other. A farmer decides to pollinate one flower of a plant with smooth seeds using pollen from plant with wrinkled seeds. The resulting pea pod has all smooth seeds.
(i) Which of the following conclusions can be drawn?
(1) The allele for smooth seeds is dominated over that of wrinkled seeds.
(2) The plant with smooth seeds is heterozygous.
(3) The plant with wrinkled seeds is homozygous.
(a) 1 only
(b) 1 and 2 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer
Answer: (c) 1 and 3 only(ii) Which of the following crosses will give smooth and wrinkled seeds in same proportion?
(a) RR X rr
(b) Rr x rr
(C) RRX Rr
(d) rrrr
Answer
Answer: (b) Rr x rr(iii) Which of the following cross can be used to determine the genotype of a plant with dominant phenotype?
(a) RR RR
(b) Rr x Rr
(c) Rr RR
(d) RR x rr
Answer
Answer: (d) RR x rr(iv) On crossing of two heterozygous smooth seeded plants (Rr), a total of 1000 plants were obtained in F1
generation. What will be the respective number of smooth and wrinkled seeds obtained in F1 generation?
(a) 750, 250
(b) 500, 500
(C) 800, 200
(d) 950, 50
Answer
Answer: (a) 750, 250(v) The characters which appear in the first filial generation are called
(a) recessive characters
(b) dominant characters
(c) lethal characters
(d) non-mendelian characters.