Heredity

Class 10 Science Chapter 8
Heredity
Important Questions

Here are some critical Chapter 8 Heredity Problems for Class 10 Science. These inquiries are intended to aid students in studying for and performing well on the CBSE Class 10 Science Examination 2024–25. Students can clear up their concerns and be ready for the exams by practising different types of questions. By answering these questions, you’ll increase your confidence while also sharpening your problem-solving abilities

Introduction

In Chapter 8 of Class 10 Science, “Heredity,” students delve into the intricate realm of genetic inheritance. This chapter elucidates the accumulation of variations that occur during reproduction, leading to the diversity observed in species. It also delves into the concept of heredity, unveiling the transmission of traits from one generation to the next, and sheds light on the mechanisms underlying the continuity of characteristics in living organisms.
Science Chapter 8 01

Class 10 Heredity Important Questions and Answers

Q 1. If a round, green seeded pea plant (RRyy) is crossed with wrinkled, yellow seeded pea plant (rrYY), the seeds produced in F_1 generation are:
Options
(a) Round and yellow
(b) Round and green
(c) Wrinkled and green
(d) Wrinkled and yellow

Ans. (a)

Explanation:
The cross between RRyy (round, green) and rrYY (wrinkled, yellow) seeds will produce RrYy (round and yellow) seeds in F_1, generation, because round and yellow are dominant traits

Q 2. Select the statements that describe characteristics of genes:
(i) Genes are specific sequences of bases in a DNA molecule.
(ii) A gene does not code for proteins.
(iii) In individuals of a given species, a specific gene is located on a particular chromosome.
(iv) Each chromosome has only one gene.
Options
(a) (i), (ii)
(b) (i), (iii)
(c) (i), (iv)
(d) (ii), (iv)

Ans. (b)

Explanation:
Gene is a particular sequence of DNA, that codes for a particular protein and is present on a particular location on a given chromosome. Genes are located on chromosomes, which usually carry many genes. All the members of a species have the same (not identical) genes located on the same chromosome. Thus, gene sequence remains the same on the chromosomes in different individuals of a species.

Q 3. What is the difference between Recessive and Dominant Traits.

Explanation:

Dominant TraitRecessive Trait
Dominant traits are always expressed when the connected allele is dominant, even if only one copy exists.Recessive traits are expressed only if both the connected alleles are recessive. If one of the alleles is dominant, then the associated characteristic is less likely to manifest.
Dominant allele is denoted by a capital letter.Recessive allele is denoted by a small letter.
Q 4. If a trait A exists in 10% of a population of an asexually reproducing species and trait B exists in 60% of the same population, which trait is likely to have arisen earlier?

Explanation:
Trait B is likely to have arisen earlier than trait A. In asexually reproducing species, genetic variations arise from small mutations or inaccuracies in DNA replication. Traits that are present in a higher percentage of the population are generally older because they have had more time to spread and become established within the population. Trait B, existing in 60% of the population, suggests it is more widespread and likely has been present for a longer period. Trait A, existing in only 10% of the population, is less common and likely more recent. Therefore, trait B is likely to have arisen earlier and had more time to proliferate in the population.

Q 5. Give the cross between RRYY x rryy for both F_1 \text{ and }F_2 generation? What are the combinations of characters produced in the F_2 generation and give reasons for the appearance of new progeny?

Explanation:

cbse class 10 Science Heredity important questions and answers

Reason for Appearance of New Progeny: The new combinations of traits in the F_2 generation result from the independent assortment of genes during meiosis in the F_1 plants. This process allows for different combinations of dominant and recessive alleles to occur, leading to new phenotypic combinations in the progeny. This phenomenon, known as genetic recombination, is a key feature of Mendelian inheritance and contributes to genetic diversity.

CBSE Class 10 Science Chapter wise Important Questions

Conclusion

oswal.io offers a thorough set of questions for learning the topic in a better way if you’re looking to further practise and improve your grasp of the concepts covered in the chapter.

Frequently Asked Questions

Ans: The law of segregation states that each individual that is a diploid has a pair of alleles (copies) for a particular trait.
Ans: All the variations do not have equal chances of survival in the environment in which they live. Depending on the nature of variations, different individuals would have different kinds of advantages. The organisms which are most adapted to the environment will survive.
Ans: Variations are the structural, functional or behavioural changes from the normal characters developed in the living organisms. Inheritable variations participate in evolution. According to Darwin, natural selection sorts out individuals with favourable variations. Such organisms will survive, reproduce more and thus, will leave more progenies. Hence, useful variations get established in nature.
Ans: According to the Mendelian experiment, violet colour (VV) is a dominant trait while white colour (ww) is a recessive trait. Hence, the colour of the flower in F1 progeny will be violet (Vw).
Ans: Deoxyribonucleic acid (DNA) present in the chromosomes of cell nucleus is the information source for making proteins.