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Question: 1
Differentiate between genotype and phenotype.
Answer: 1
1-68Genotype: Genotype is the genetic complement i.e the genes is an individual for a particular trait e.g"Rr" &"Rr" are alleles for red color."rr" are alleles for white colour.
Question: 2
What is test cross?Who devised it?
Answer: 2
2-68Mendel devised test cross.
Question: 3
What is test cross? Give its significance?
Answer: 3
3-68Test 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
Significance of test cross is that we can know the genotype of an organism
Question: 4
What are jumping genes?
Answer: 4
4-68Jumping genes do not reside peacefully on their loci; they keep on hopping on different loci on the same chromosomes or other chromosomes.
Question: 5
Differentiate between dominant and recessive traits.
Answer: 5
5-68Dominant trait: They trait which is controlled by dominant gene or allele us called dominant trait.
Question: 6
What is law of segregation?
Answer: 6
6-68The two coexisting alleles for each trait in an individual segregate from each other at meiosis, so that each gamete has only one the two alleles.Alleles unite again random fertilization of gametes when zygote is formed.
Question: 7
Explain gene and allele.
Answer: 7
7-68Gene is a part a DNA which can provide instruction for the synthesis of a protein.It is unit of inheritance.
Question: 8
Differentiate between homozygous and heterozygous.
Answer: 8
8-68Homozygous: If alleles of a gene pair are in similar from they are called homozygous.
Question: 9
What is beanbag genetics? Explain.
Answer: 9
9-68Beanbag genetics means that alleles are like a bean bag.The entire bean bag full of beans is the gene of the population.In the bean bag approach we can imagine the entire gene pool comprising all the alleles for all different traits at once,or we can just focus on some subset,such as all the alleles for a single trait
Question: 10
Define gene and locus.
Answer: 10
10-68Gene is unit of inheritance. Or it may be defined as
Question: 11
What is a true breeding variety?
Answer: 11
11-68A true breeding variety upon self fertilization always produced offsprings identical to their parents.
Question: 12
Differentiate between monohybrid and dihybrid cross.
Answer: 12
12-68Monohybrid: A cross between two organisms which differ only in one character is called monohybrid cross.
Question: 13
What is erythroblastosis foetalis?
Answer: 13
13-68Due to maternal-fetal Rh incompatibility,there is destruction of fetal RBCs,and fetus become anemic,The anemic fetus starts to release many immature erythroblasts into his blood stream.That is why this hemolytic diseases of new borne is called erythroblastosis foetalis.
Question: 14
Define probability.
Answer: 14
14-68It is the chance of an event to occur.
Question: 15
Why is blood group AB called as universal recipient?
Answer: 15
15-68AB 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: 16
What is contribution of Carl Correns in genetics?
Answer: 16
16-68Carl Correns discovered the phenomenon of incomplete dominance.
He crossed red flowered 4 O clock plant with while flowered 4 O clock plant.In f1pink flowers were produced instead of red color was dominant.He again crossed pink flowers from F1,in F2 red,pink white flowers obtained with ratio 1:2:1 respectively.
He crossed red flowered 4 O clock plant with while flowered 4 O clock plant.In f1pink flowers were produced instead of red color was dominant.He again crossed pink flowers from F1,in F2 red,pink white flowers obtained with ratio 1:2:1 respectively.
Question: 17
Define co-dominance.
Answer: 17
17-68Different alleles of a gene that are both expressed in a heterozygous condition are called co-dominance e.g MN blood group system.
Question: 18
Differentiate between multiple alleles and polygenes..
Answer: 18
18-68Multiple alleles: If a gene has more than two alternate forms these are called multiple alleles.For example alleles for ABO blood group. E.g,alleles for ABO blood group.
Question: 19
State Law of independent assortment.
Answer: 19
19-68When two contrasting pairs of traits are followed in the same cross,their alleles are assorted independently into gametes.
Question: 20
What is dominance?Discuss over dominance.
Answer: 20
20-68Dominance 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.
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: 21
What do you know about co-dominance?
Answer: 21
21-68Different alleles of a gene that are both expressed in a heterozygous condition is called co-dominance.
Question: 22
Define recombination frequency.Give an example.
Answer: 22
22-68It is the proportion of recombinant type between two gene pairs as compared to sum of all combinations.
Question: 23
What are multiple alleles,give its example?
Answer: 23
23-68When a gene exists in more than two alternate forms called multiple alleles.Blood group ABO is an example of multiple alleles.
Question: 24
Define incomplete dominance,Give example
Answer: 24
24-68When 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.
Example: flower colouring in 4'0 clock plant.
Question: 25
Define product rule and pseudoautosomal genes.
Answer: 25
25-68The 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.
Question: 26
How does ABO incompatibility protect the developing baby against Rh-
Answer: 26
26-68Incompatiability
Rh sensitization of Rh mother can be easily avoided If mother is given an injection of Rh antiserum during early pregnancy and immediately after birth.
Rh sensitization of Rh mother can be easily avoided If mother is given an injection of Rh antiserum during early pregnancy and immediately after birth.
Question: 27
Differentiate between linkage and linkage group.
Answer: 27
27-68Linkage: linkage is a phenomenon in which all the genes on a chromosomes stay together is called linkage.
Question: 28
Differentiate between co-dominance and over dominance.
Answer: 28
28-68Co-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.
Question: 29
Define polygenic Inheritance.Give example.
Answer: 29
29-68Polygenic inheritance is that which is controlled by more than two pairs of gene are called polyegneic traits.For example wheat grain color,human eye and skin color.
Question: 30
Assign the sex of the human having XO,XXX,XXY and XYY chromosomes.
Answer: 30
30-68Species XX XY XO XXY
Human Female Male Male Male
Drosophila Female Male Female Female
Human Female Male Male Male
Drosophila Female Male Female Female
Question: 31
What is the product rule?
Answer: 31
31-68When two independent events are occurring simultaneously like in dihybrid cross,the ratio of each joint phenotypic combination can be obtained by multiplying the probabilities of individual phenotypes. It is called product rule.
Question: 32
What is Pleiotropy? Give one example.
Answer: 32
32-68When 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: 33
What is XO-XX mechanism of sex determination?
Answer: 33
33-68This 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.
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: 34
What is Bombay Phenotype?
Answer: 34
34-68When in an individuals RBCs lack A and B antigens although the do not contain Ia and Ib genes.They are phenotypically like O blood group but are not genotypically like O.Their phenotype is called Bombay phenotype.
Question: 35
What is type II diabetes or NIDDM?
Answer: 35
35-68Type II diabetes or NIDDM.It account for 90% of all diabetic patients.These person produce some endogenous insulin themselves,but their body cells fail to respond to insulin and cannot take up glucose from body.They develop some sort of insulin resistance.
Question: 36
Define linkage and give its one disadvantage.
Answer: 36
36-68Phenomenon of staying together of all the genes of a chromosomes is called linkage.
Its disadvantage is that,alleles cannot be assorted independently and no new recombinations are formed.
Its disadvantage is that,alleles cannot be assorted independently and no new recombinations are formed.
Question: 37
In bird's the female is heterogametic. How?
Answer: 37
37-68In 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: 38
What is hypophosphatemic rickets?
Answer: 38
38-68It is an X linked dominant trait.It is rare hereditary disease.it does not result from vitamin D deficiency but its cause is a genetic communication failure at molecular level.The genes encoding bone proteins never receive vitamin D message to function.
Question: 39
Differentiate between multifactorial and polygenic traits.
Answer: 39
39-68Multifactorial traits: Traits which are controlled by many genes (polygenes) with combination of environment are called multifactorial traits.
Question: 40
What do you known about protanopia and tritanopia?
Answer: 40
40-68Protonopia is red colour blindness while tritonopia is blue color blindness.
Question: 41
Differentiate between continuous and discontinuous variations.
Answer: 41
41-68Continuous 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.
Question: 42
Differentiate between quantitative and qualitative variations.
Answer: 42
42-68Quantitative variations: In Qualitative variations difference is small and less striking.Many traits like skin color,height and weight exhibit continuous quantitative variation.
Question: 43
Define SRY gene.
Answer: 43
43-68SRY stands for sexual determining region of y.It is the part of Y-chromosomes in human males which is responsible for male characters of maleness.
Question: 44
how can you calculate frequency between two linked genes?
Answer: 44
44-68Frequency between two linked genes can be calculated by the following formula
Recombination frequency=Recombination type
--------------------------* 100
Sum of all combinations
Recombination frequency=Recombination type
--------------------------* 100
Sum of all combinations
Question: 45
Explain genic system for determination of sex.
Answer: 45
45-68Many 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: 46
What is heterogametic individual?Give example.
Answer: 46
46-68Male grasshopper is XO because it has only one X chromosome.The other sex chromosome is missing entirely.Male is heterogametic because it forms two type of sperms,half the sperms have X chromosome while the other half are without any sex chromosome.
Question: 47
How sex is determined in plants?
Answer: 47
47-68Plants 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: 48
What is nullo gametes?
Answer: 48
48-68A gamete without sex chromosomes is called nullo gamete.For Example Grasshopper male produce 50% nullo gametes and 50% with sex chromosomes.
Question: 49
Define pleiotropy. Give two examples.
Answer: 49
49-68When a gene more than one trait it is called pleiotropy. For example gene for eye colour in Drosophila also controls shape of spermathecae.
Question: 50
What is Mody?Write its causes.
Answer: 50
50-68About 2 to 5% of type II diabetics get the disease early in the life before 25 year of age.It is called maturity onset diabetes of the young(Mody).Mody can be inherited as an autosomal dominant trait.
Question: 51
What is haemophillia?Give its type.
Answer: 51
51-68Haemophilia is rare x-linked recessive trait.Haemophilic's blood does not clot properly after an injury,because it has either a reduction or malfunction or complete absence of blood clotting factor.
It types are Haemophilia A,haemophilia B and haemophila C.
It types are Haemophilia A,haemophilia B and haemophila C.
Question: 52
Compare between epistasis and poleiotropy.
Answer: 52
52-68Epistasis: When an effect caused by a gene pair on one locus interferes with or hides the effect caused by another gene or gene pair at another locus,it is called epistasis.
Question: 53
What are sex limited traits?Give an example.
Answer: 53
53-68Sex limited traits are present only in one sex due to anatomical differences.Such trait affects a structure or function of the body present in only males or only females.For example genes for milk yield in dairy cattle affect only cows.
Question: 54
Differentiate between autosome and sex chromosomes.
Answer: 54
54-68Autosome chromosomes: Chromosomes which do not contain genes for sex determination or chromosomes other than sex chromosomes are called autosomes.
Question: 55
How sex is determined in yeast?
Answer: 55
55-68Sex determination in yeast depends upon genic system.In this system the sexes are determined by simple allelic difference at a small number of gene loci e.g,a and a are the two mating types or sexes of yeast controlled by MAT a and MAT.a alleles respectively.
Question: 56
Differentiate between homogametic and heterogametic organism.
Answer: 56
56-68Homogametic organism: When an organism produce all the gametes of same type it is called homogametic.
Question: 57
Explain testicular feminization syndrome.
Answer: 57
57-68Testicular feminization syndrome is a rare X linked recessive trait.Although the persons affected by this trait have a set of XY chromosome.Yet tfm gene on their X chromosome develops them physically into females.They have breast,female genitalia a blind vagina but no uterus,degenerated testis are also present in abdomen.Such individuals are happily married as female but are sterile.it is an androgen insensitivity syndrome.Male sex hormone testoterone has no effect on them.
Question: 58
Differentiate between gene and allele.
Answer: 58
58-68Gene: Gene is the basic unit of biological information.In fact DNA allstorts of biological information coded in the sequence of its bases in a linear order and genes are actually parts of DNA comprising its base sequences.
Question: 59
Give significance of test cross.
Answer: 59
59-68Mendel devised a cross called test cross,which is used to test the genotype of an individual showing a dominant phenotype.This cross finds out the homozygous or heterozygous nature of the genotype.
Question: 60
Differentiate between tritanopia and deutranopia.
Answer: 60
60-68Tritanopia: Tritanopia is blue colour blindness.
Question: 61
What is tetrad?
Answer: 61
61-68Each pair of homologous chromosome which consists of four chromatids is called tetrad.
Question: 62
What are sex influenced traits?Give an example.
Answer: 62
62-68Sex influencing traits occurs in both males and females but more common in one sex.It is controlled by an allele that is dominant in one sex but recessive in other.The difference in expression is due hormonal difference in two sexes.E.g, patteren baldness is sex influenced trait.
Question: 63
Define gene linkage and gene linkage groups.
Answer: 63
63-68Gene 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.
Question: 64
Differentiate between population & gene pool.
Answer: 64
64-68Population: Any group of interbreeding organisms of the same species that exist together in both time and space is called a population.e.g 100 diploid plants of pea in a field is an example of population.
Question: 65
What is monochromacy?
Answer: 65
65-68Monochromacy means only one colour can be perceived by the colour blind person.Monochromacy is true colour blindness.
Question: 66
Two Normal parents have an albino child.What is the probability that their next child will also be an albino?
Answer: 66
66-683 of their sons will be normal and one will be albino that is the ratio is
Normal : Albino
3 1
Normal : Albino
3 1
Question: 67
What is epistasis?Ho it differs from dominance?
Answer: 67
67-68Epistasis: An effect caused by a gene or gene pair at one locus interferes with or hides the effect caused by another gene or gene pair at another locus,such a phenomenon of gene interaction is called epistasis.
Epistasis must not be confused with dominance.
Epistasis must not be confused with dominance.
Question: 68
Define crossing over.Give its importance.
Answer: 68
68-68Mendel devised a cross called test cross,which is used to test the genotype of an individual showing a dominant phenotype.It is a mating in which an individual showing a dominant phenotype is crossed with an individual showing its recessive phenotype.significance of test cross is it is used to check the homozygosity & heterozygosity of the dominant parent.
