Homozygous is a genetic condition or the genetic state where an individual has inherited the same DNA sequence for a particular gene from both parents. We can otherwise say that homozygous refers to a condition in which an organism has identical alleles, e.g., TT, RR, rr, tt. A homozygous individual produces only one type of gametes.

Heterozygous is a genetic condition in which two different alleles are present at a particular gene locus. In other words, it is a condition in which a person has inherited different forms of a particular gene from each parent. By different forms, we generally mean that there are different portions of the gene where the sequence is different. Examples of heterozygosity: Tt, Rr, etc.

Phenotype is defined as the external appearance of an individual for any trait. It is observable and is determined by different combinations of alleles. For example, in the pea plant, the coloured flower represented by the genotype CC and Cc and the white flower represented by the genotype cc are the two phenotypes.

Sex linkage is the phenotypic expression of an allele that is dependent on the gender of the individual and is directly concerned with the sex chromosomes. The progeny produced are more of parental type and fewer recombinants.

What is reciprocal cross?

The reciprocal cross involves testing the role of parental sex on the inheritance pattern in breeding experiments. It involves crossing a pair of parents with the sexes reversed resulting in two reciprocal crosses. For example, in the first cross pollens taken from tall plants are transferred to the stigma of dwarf plants, then in the reciprocal cross would use the pollens of dwarf plants to pollinate the stigmas of tall plants.

Write any two differences between genotype and phenotype.

Basis Genotype Phenotype Definition The genotype gives the genetic constitution of an organism i.e., it gives the description of genes present in an organism. The characteristic or trait that is visible in an organism is called its phenotype. Basis Genotype Phenotype Example For example, a pure or homozygous tall plant has the genotype of TT, and hybrid or heterozygous tall has the genotype of Tt. For example, 'tall' or 'dwarf' are the external appearance of an organism and are called phenotypes.

Phenotype is defined as the external appearance of an individual for any trait. It is observable and is determined by different combinations of alleles. For example, in the pea plant, the coloured flower represented by the genotype CC and Cc and the white flower represented by the genotype cc are the two phenotypes.

Heterozygous is a genetic condition in which two different alleles are present at a particular gene locus. In other words, it is a condition in which a person has inherited different forms of a particular gene from each parent. By different forms, we generally mean that there are different portions of the gene where the sequence is different. Examples of heterozygosity: Tt, Rr, etc.

E M B I B E

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR BIOLOGY>Chapter 5 - Principles of Inheritance and Variation>Chattisgarh Board-2018>Q 2

EASY

12th Chhattisgarh Board

IMPORTANT

Earn 100

Define homozygous.

Important Questions on Principles of Inheritance and Variation

EASY

12th Chhattisgarh Board

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR BIOLOGY>Chapter 5 - Principles of Inheritance and Variation>Chattisgarh Board-2018>Q 3

Define heterozygous.

EASY

12th Chhattisgarh Board

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR BIOLOGY>Chapter 5 - Principles of Inheritance and Variation>Chattisgarh Board-2018>Q 4

Define phenotype.

HARD

12th Chhattisgarh Board

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR BIOLOGY>Chapter 5 - Principles of Inheritance and Variation>Chattisgarh Board-2018>Q 5

What is the maternal effect? Explain with a suitable example.

HARD

12th Chhattisgarh Board

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR BIOLOGY>Chapter 5 - Principles of Inheritance and Variation>Chattisgarh Board-2018>Q 6

Explain the sex determination process in humans with the help of ray diagram.

HARD

12th Chhattisgarh Board

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR BIOLOGY>Chapter 5 - Principles of Inheritance and Variation>Chattisgarh Board-2018>Q 7

Write the main characteristic features of colour blindness. What will be the hereditary of the offspring when a colourblind man marries with a normal female? Explain it with ray diagram.

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12th Chhattisgarh Board

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR BIOLOGY>Chapter 5 - Principles of Inheritance and Variation>Chattisgarh Board-2019>Q 8

What is co-dominance?

MEDIUM

12th Chhattisgarh Board

IMPORTANT

EMBIBE CHAPTER WISE PREVIOUS YEAR PAPERS FOR BIOLOGY>Chapter 5 - Principles of Inheritance and Variation>Chattisgarh Board-2019>Q 9

What is sex linkage?

MEDIUM

12th Chhattisgarh Board