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

Question # 1

What is Pleiotropy? Give one example.

Ans 1: When a single gene affects two or more traits the phenomenon is called pleiotropy. E.g, genes that effect growth rate in human also influence both weight and height.

Question # 2

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 # 3

What is dominance?Discuss over dominance.

Ans 1: Dominance is a physiological effect of an allele over its partner allele on the same locus.
Over dominance: This relation is very interesting because the over dominant heterozygote exceed in quantity than phenotypic expression of both the homozygotes. In fruit fly Drosophila the heterozygote(W⁺/w) has more quantity of florescent pigments in eyes than wild (w⁺/w^{+) or white eye (w/w) homozygote.}

Question # 4

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.

Question # 5

Why is blood group AB called as universal recipient?

Ans 1: AB blood group is called recipient because they have both A and B antigens but no antibodies,so they can easily accept or receive any type of blood group i.e,A,B,AB or O

Question # 6

Differentiate between autosome and sex chromosomes.

Ans 1: Autosome chromosomes: Chromosomes which do not contain genes for sex determination or chromosomes other than sex chromosomes are called autosomes.
Ans 2: Sex chromosomes: Chromosomes which play role in sex determination are called sex chromosomes.

Question # 7

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 # 8

What is test cross?Who devised it?

Ans 1: Mendel devised test cross.

Question # 9

Differentiate between quantitative and qualitative variations.

Ans 1: Quantitative variations: In Qualitative variations difference is small and less striking.Many traits like skin color,height and weight exhibit continuous quantitative variation.
Ans 2: Qualitative variations: In qualitative variations differences are large and more obvious,some traits like pea seed shape show discontinuous qualitative variations with two sharply distinct phenotypes like round and wrinkled.

Question # 10

Define gene linkage and gene linkage groups.

Ans 1: Gene linkage: Gene linkage is the tendency of DNA sequences that are close together on a chromosomes to be inherited together during the meiosis phase of sexual reproduction.
Ans 2: Gene linkage groups: In genetics all of the genes on a single chromosome are inherited as a group i.e during cell division they act and move as unit rather than independently.

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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 is Pleiotropy? Give one example.

In bird's the female is heterogametic. How?

What is dominance?Discuss over dominance.

What is XO-XX mechanism of sex determination?

Why is blood group AB called as universal recipient?

Differentiate between autosome and sex chromosomes.

Explain genic system for determination of sex.

What is test cross?Who devised it?

Differentiate between quantitative and qualitative variations.

Define gene linkage and gene linkage groups.

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 is Pleiotropy? Give one example.

In bird's the female is heterogametic. How?

What is dominance?Discuss over dominance.

What is XO-XX mechanism of sex determination?

Why is blood group AB called as universal recipient?

Differentiate between autosome and sex chromosomes.

Explain genic system for determination of sex.

What is test cross?Who devised it?

Differentiate between quantitative and qualitative variations.

Define gene linkage and gene linkage groups.

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

Define polygenic Inheritance.Give example.

What is heterogametic individual?Give example.

What are sex limited traits?Give an example.

What is law of segregation?

Define co-dominance.

How sex is determined in yeast?

Differentiate between homozygous and heterozygous.

Differentiate between dominant and recessive traits.

What is contribution of Carl Correns in genetics?

How sex is determined in plants?

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

What is tetrad?

Differentiate between homozygous and heterozygous.

Compare between epistasis and poleiotropy.

What are sex limited traits?Give an example.

How sex is determined in yeast?

Two Normal parents have an albino child.What is the probability that their next child will also be an albino?

Differentiate between tritanopia and deutranopia.

What is Bombay Phenotype?

Define product rule and pseudoautosomal genes.

What are sex influenced traits?Give an example.

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

Explain genic system for determination of sex.

What is erythroblastosis foetalis?

What is Pleiotropy? Give one example.

What are multiple alleles,give its example?

What is monochromacy?

Explain gene and allele.

Explain testicular feminization syndrome.

What is haemophillia?Give its type.

What is test cross? Give its significance?

How sex is determined in plants?

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

What is test cross? Give its significance?

Define gene linkage and gene linkage groups.

Differentiate between multifactorial and polygenic traits.

Differentiate between dominant and recessive traits.

Define SRY gene.

What is Pleiotropy? Give one example.

What is XO-XX mechanism of sex determination?

What is monochromacy?