Class 10 Biology Chapter 2
Genetics: Mendel's law of Inheritance
Important Questions

Here, you'll find important questions related to Chapter 2: Genetics: Mendel's law of Inheritance for ICSE Class 10 Biology. These questions have been crafted to assist students in their preparation for the ICSE Class 10 Biology Examination in 2023–24. By practising various question types, students can clarify their doubts, enhance their exam readiness, boost their confidence, and refine their problem-solving skills.

Introduction

In the second chapter of ICSE Class 10 Biology, you will embark on a fascinating journey into the world of genetics, specifically delving into Mendel's Law of Inheritance. This chapter holds immense significance in the realm of biology, as it lays the foundation for understanding how traits and characteristics are passed from one generation to another. As you delve deeper into the intricacies of genetics, you will not only grasp the essential concepts but also equip yourself with the knowledge required to answer important questions on ICSE Class 10 Biology Genetics. These questions, often regarded as biology important questions for Class 10 ICSE, form the basis of your understanding of Mendelian inheritance and its applications. So, let's embark on this genetic voyage, unravelling the mysteries of inheritance and exploring the pivotal role it plays in the fascinating world of biology.

What are Genetics: Mendel's law of Inheritance  ?

Genetics is the branch of biology that explores the mechanisms responsible for the inheritance of traits from one generation to the next. Within this fascinating field, one of the cornerstone principles is Mendel's Law of Inheritance, which was formulated by Gregor Mendel, an Austrian scientist and Augustinian friar, in the 19th century.
Mendel's Law of Inheritance comprises several fundamental concepts:

• Dominance and Recessiveness: Mendel observed that certain traits in pea plants were dominant, meaning they would appear in the offspring when even one parent possessed the dominant allele. In contrast, recessive traits would only manifest when both parents carried the recessive allele.
• Segregation: Mendel proposed the law of segregation, which states that during the formation of gametes (sperm and egg cells), the two alleles (gene variants) for a trait separate or segregate from each other, ensuring that each offspring inherits one allele from each parent.
• Independent Assortment: Mendel's law of independent assortment suggests that alleles for different traits segregate independently of each other during gamete formation. This principle helps explain the diversity of traits observed in offspring.
• Punnett Squares: To predict the probability of specific traits appearing in offspring, Mendel introduced Punnett squares—a graphical tool used to determine potential allele combinations resulting from the union of gametes.

Mendel's work with pea plants laid the foundation for our understanding of genetics, inheritance, and the transmission of genetic traits across generations. It has far-reaching implications in fields such as medicine, agriculture, and evolutionary biology. Mendel's Law of Inheritance is a fundamental concept covered in ICSE Class 10 Biology and is crucial for students preparing for ICSE Class 10 Biology Genetics questions, as it provides the basis for comprehending how genes are inherited and expressed in living organisms.

Class 10 Biology Genetics: Mendel's law of Inheritance Important Questions and Answers

Q1. Genetics is a branch of biology dealing with:

Options

(a) Heredity in living beings
(b) Variation in living beings
(c) Both heredity and variation
(d) None of these

Ans. (c) Heredity in living beings

Q2. The diagram shows a cross between heterozygous tall pea plants :

Which of the following statements is not correct?

Options

(a) Offspring E and H are both homozygous.
(b) Offspring F and G are both heterozygous.
(c) The phenotypes of offspring E, F and G are the same.
(d) The ratio of different phenotypes in the offspring is 1 : 1.

Ans. (d)
Explanation:
The cross between heterozygous tall (Tt) pea plants will show a phenotypic ratio of 3 (TT,Tt) : 1 (tt).

Q3. Define Alleles.

Explanation:
Alleles: Alleles are the alternative forms of the same gene. For example, tallness and dwarfness are the two alternative forms of a gene for height and are called alleles. Similarly, attached earlobes and free earlobes are alleles for the type of ear lobes.

Q4. Define mutation and give its significance.

Explanation:
Any change in genetic composition of an individual brought about by internal or external factors is called mutation. Mutations play a significant role in the evolution and speciation because they cause variation. However, some harmful mutations cause diseases.

Q5. Differentiate between haemophilia and colour blindness.

Explanation:‍

ICSE Class 10 Biology Chapter wise Important Questions

Conclusion

Mendel's laws of inheritance have illuminated the intricate world of genetics and heredity. To solidify their knowledge and excel in this area, it is highly recommended to explore additional resources, including ICSE Class 10 biology questions and answers. These resources provide valuable practice and insights that can significantly enhance one's understanding.For those seeking to further enrich their learning experience and consolidate their grasp of Mendel's laws and inheritance patterns, Oswal.io offers a comprehensive collection of questions and materials.

Frequently Asked Questions

Q1 : What are the three laws of inheritance proposed by Mendel?

Ans: The three laws of inheritance proposed by Mendel include:

• Law of Dominance
• Law of Segregation
• Law of Independent Assortment

Q2 : Which is the universally accepted law of inheritance?

Ans:  Law of segregation is the universally accepted law of inheritance. It is the only law without any exceptions. It states that each trait consists of two alleles which segregate during the formation of gametes and one allele from each parent combines during fertilisation.

Q3 : Why is the law of segregation known as the law of purity of gametes?

Ans: The law of segregation is known as the law of purity of gametes because a gamete carries only a recessive or a dominant allele but not both the alleles.

Q4 : Why was the pea plant used in Mendel’s experiments?

Ans:  Mendel picked pea plants in his experiments because the pea plant has different observable traits. It can be grown easily in large numbers and its reproduction can be manipulated. Also, pea has both male and female reproductive organs, so they can self-pollinate as well as cross-pollinate.

Q5 : What was the main aim of Mendel’s experiments?

Ans: The main aim of Mendel’s experiments was:

• To determine whether the traits would always be recessive.
• Whether traits affect each other as they are inherited.
• Whether traits could be transformed by DNA.