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

Question # 1

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.

Question # 2

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 # 3

What do you known about protanopia and tritanopia?

Ans 1: Protonopia is red colour blindness while tritonopia is blue color blindness.

Question # 4

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

Ans 1: 3 of their sons will be normal and one will be albino that is the ratio is
Normal : Albino
3 1

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

Define gene and locus.

Ans 1: Gene is unit of inheritance. Or it may be defined as
Ans 2: The sequence of nucleotides which determines the amino acid sequence of a protein is called gene and the position of a gene on the chromosomes is known as locus.

Question # 7

Explain gene and allele.

Ans 1: Gene is a part a DNA which can provide instruction for the synthesis of a protein.It is unit of inheritance.
Ans 2: Allele is an alternate from of gene.

Question # 8

Differentiate between continuous and discontinuous variations.

Ans 1: Continuous variations: In Continuous variations many intermediate forms of a trait are present and organism show very small difference for a trait.For example skin color,eye color.
Ans 2: Discontinuous variations: In discontinuous variations very sharp difference is present and no intermediate forms are present for a trait.For example tongue rolling,attached or free pinna.

Question # 9

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 # 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

Define gene linkage and gene linkage groups.

Differentiate between co-dominance and over dominance.

What do you known about protanopia and tritanopia?

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

Define product rule and pseudoautosomal genes.

Define gene and locus.

Explain gene and allele.

Differentiate between continuous and discontinuous variations.

Differentiate between autosome and sex chromosomes.

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

Define gene linkage and gene linkage groups.

Differentiate between co-dominance and over dominance.

What do you known about protanopia and tritanopia?

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

Define product rule and pseudoautosomal genes.

Define gene and locus.

Explain gene and allele.

Differentiate between continuous and discontinuous variations.

Differentiate between autosome and sex chromosomes.

What is XO-XX mechanism of sex determination?

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

Define gene linkage and gene linkage groups.

How sex is determined in yeast?

What is haemophillia?Give its type.

What is type II diabetes or NIDDM?

Differentiate between autosome and sex chromosomes.

Differentiate between continuous and discontinuous variations.

Differentiate between gene and allele.

Differentiate between linkage and linkage group.

Define co-dominance.

Differentiate between dominant and recessive traits.

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

Define linkage and give its one disadvantage.

Define gene linkage and gene linkage groups.

Differentiate between linkage and linkage group.

Differentiate between genotype and phenotype.

Explain testicular feminization syndrome.

What is erythroblastosis foetalis?

Define crossing over.Give its importance.

Differentiate between continuous and discontinuous variations.

What are jumping genes?

Define incomplete dominance,Give example

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

Define probability.

How sex is determined in yeast?

What do you known about protanopia and tritanopia?

Differentiate between multiple alleles and polygenes..

What is XO-XX mechanism of sex determination?

Give significance of test cross.

What is nullo gametes?

State Law of independent assortment.

Define product rule and pseudoautosomal genes.

How does ABO incompatibility protect the developing baby against Rh-

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

Why is blood group AB called as universal recipient?

What is beanbag genetics? Explain.

How sex is determined in plants?

Differentiate between dominant and recessive traits.

What is nullo gametes?

Differentiate between multiple alleles and polygenes..

Differentiate between tritanopia and deutranopia.

In bird's the female is heterogametic. How?