Get the 12th Class Fsc Biology Online Preparation for chapter 22 (Variation and Genetics)

Question # 1

What are jumping genes?

Ans 1: Jumping genes do not reside peacefully on their loci; they keep on hopping on different loci on the same chromosomes or other chromosomes.

Question # 2

What is tetrad?

Ans 1: Each pair of homologous chromosome which consists of four chromatids is called tetrad.

Question # 3

Differentiate between co-dominance and over dominance.

Ans 1: Co-dominance: Different alleles of a gene that are both expressed in a heterozygous condition are called codominant and this phenomenon is called codominance.e.g if a man of M blood group marries a woman of N blood group,all their children will have MN blood group.
Ans 2: Over-dominance: This dominance relation is fascinating because the overdominant heterozygote exceeds in quantity the phenotypic expression of both the homozygotes.e.g In fruit fly Drosophila the heterozygote W⁺/W or white eye w/w homozygotes.

Question # 4

Define incomplete dominance,Give example

Ans 1: When the phenotype of the heterozygote is intermediate between phenotypes of the two homozygotes,it is called incomplete dominance.
Example: flower colouring in 4'0 clock plant.

Question # 5

Define product rule and pseudoautosomal genes.

Ans 1: The genes which are located both on x and y chromosomes are called x and y linked genes or pseudoautosomal genes because their pattern of inheritance is like autosomal genes.
Ans 2: Product rule: When we multiply probabilities of two different event,this phenomenon is called product rule.

Question # 6

Explain genic system for determination of sex.

Ans 1: Many species of eukaryotic micro-organisms like yeast do not have sex chromosomes.These depend on genic system for determination of sex.In this system the sexes are specified by simple allelic differences at small number of gene loci.

Question # 7

What is test cross? Give its significance?

Ans 1: Test cross is a cross used to test the genotype of an organism showing dominant phenotype.
Significance of test cross is that we can know the genotype of an organism

Question # 8

How sex is determined in plants?

Ans 1: Plants show a variety of sexual situations.Some species like Ginkgo are dio-ecious having plants of separate sexes.Male plants produce flower with only stamens and female plants produce flower with only carpels.Some dioecious plants have a difference of sex chromosome between the sexes.These have an X-Y system.These plants typically exhibit an X-choromosome autosome balance system for sex determination.

Question # 9

In bird's the female is heterogametic. How?

Ans 1: In birds female is heterogametic because she produce two different types of gametes and sex of new borne is determined by the type of female gamete which fertilize the sperm.

Question # 10

What is XO-XX mechanism of sex determination?

Ans 1: This pattern of Inheritance is found in grasshopper and protenor bug.Male is XO because male has one x chromosomes,the other x chromosomes is missing and female is xx,it is homogametic because it forms all gametes of same type with one X chromosome.Male is heterogametic because it forms two types sperms: half sperms have X chromosomes and other half are without X chromosomes.
When sperm with X chromosomes is fused with an egg having X chromosomes female offspring is produced and when sperms without X chromosomes is fused with egg then male offspring will be produced.

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12th Class Fsc Biology Online Preparation for chapter 22 (Variation and Genetics)

Online Short Questions For Chapter 8 "12th Class Biology Chapter 22 Short Questions Preparation "

Biology - 12th Class Biology Chapter 22 Short Questions Preparation

What are jumping genes?

What is tetrad?

Differentiate between co-dominance and over dominance.

Define incomplete dominance,Give example

Define product rule and pseudoautosomal genes.

Explain genic system for determination of sex.

What is test cross? Give its significance?

How sex is determined in plants?

In bird's the female is heterogametic. How?

What is XO-XX mechanism of sex determination?

Prepare Complete Set Wise Questions For Chapter 8 "12th Class Biology Chapter 22 Short Questions Preparation "

Set 1

Set 2

Set 3

Set 4

Set 5

Set 6

12th Class Biology Chapter 22 Short Questions Preparation - Set 1

What are jumping genes?

What is tetrad?

Differentiate between co-dominance and over dominance.

Define incomplete dominance,Give example

Define product rule and pseudoautosomal genes.

Explain genic system for determination of sex.

What is test cross? Give its significance?

How sex is determined in plants?

In bird's the female is heterogametic. How?

What is XO-XX mechanism of sex determination?

12th Class Biology Chapter 22 Short Questions Preparation - Set 2

How does ABO incompatibility protect the developing baby against Rh-

Define co-dominance.

Differentiate between quantitative and qualitative variations.

Define probability.

What is Pleiotropy? Give one example.

State Law of independent assortment.

Differentiate between gene and allele.

Explain testicular feminization syndrome.

Compare between epistasis and poleiotropy.

Define SRY gene.

12th Class Biology Chapter 22 Short Questions Preparation - Set 3

Differentiate between dominant and recessive traits.

What is epistasis?Ho it differs from dominance?

What is XO-XX mechanism of sex determination?

Differentiate between quantitative and qualitative variations.

Define recombination frequency.Give an example.

What is beanbag genetics? Explain.

Differentiate between tritanopia and deutranopia.

In bird's the female is heterogametic. How?

Differentiate between monohybrid and dihybrid cross.

Differentiate between homozygous and heterozygous.

12th Class Biology Chapter 22 Short Questions Preparation - Set 4

How sex is determined in plants?

What do you know about co-dominance?

What is beanbag genetics? Explain.

Differentiate between homozygous and heterozygous.

What is heterogametic individual?Give example.

Explain testicular feminization syndrome.

Explain genic system for determination of sex.

Assign the sex of the human having XO,XXX,XXY and XYY chromosomes.

What is tetrad?

how can you calculate frequency between two linked genes?

12th Class Biology Chapter 22 Short Questions Preparation - Set 5

Define crossing over.Give its importance.

Differentiate between gene and allele.

What is Bombay Phenotype?

Differentiate between homozygous and heterozygous.

Differentiate between dominant and recessive traits.

What is beanbag genetics? Explain.

What is erythroblastosis foetalis?

What is haemophillia?Give its type.