Principles Of Inheritance And Variation Flashcards

1
Q

Well known Indian breed of cow in Punjab -

A

Sahiwal

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2
Q

Gregor Mendel conducted hybridisation experiments on GARDEN PEA for _____years . From _to ____ .

A

7 yrs

1856-1863

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3
Q

During Mendel’s investigations into _____ it was for the first time that statistical analysis and mathematical logic were applied to biology .

A

Inheritance patterns

Mendels laws of inheritance

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4
Q

Mendels experiments had a _____ ,which gave greater credibility to the data he collected .

A

Large sampling size

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5
Q

Mendel conducted_______ experiments on ____breeding pea lines .

A

Artificial pollination /cross pollination experiments

True breeding

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6
Q

A true breeding line is one that , having undergone _________ , shows stable _____and _____for several generations .

A

Continuous self pollination
Stable trait inheritance
Expression

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7
Q

Mendel selected _____true breeding pea plant varieties as pairs , which were similar except for 1 character with contrasting traits .

A

14

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8
Q

Name the contrasting traits studied by Mendel in pea -

A
Stem height 
Flower colour
Flower position
Seed colour 
Seed shape 
Pod colour 
Pod shape
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9
Q

In F1 generation , ___trait as observed and in F2 , both the traits were expressed in the ratio_____ ( phenotypic ratio in monohybrid cross )

A

One of the parental trait only

3:1

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10
Q

Segregation meaning -

A

Separation ; isolation

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11
Q

Recessive parental trait is expressed without any _____ in the ____generation .

A

Blending

F2

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12
Q

When plants produce gametes by meiosis , the alleles of the parental pair ___ from each other and only 1 allele is transmitted to a gamete .

A

Segregate /separate

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13
Q

Segregation of alleles is a _____process .and there is ___chance of a gamete containing either allele .

A

Random

50%

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14
Q

Punnett square was developed by a ____ , named Reginald C Punnett .

A

British geneticist

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15
Q

When Mendel self -pollinated the F2 plants , he found that -

A

Dwarf F2 continued to generate dwarf plants in F3 and F4 .

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16
Q

Test cross is used to determine __composition .

A

Genotypic

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17
Q

______can be calculated using mathematical probability , by simply looking at the phenotype of a dominant trait , it is not possible to know ______ .

A

Genotypic ratios

Genotypic composition

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18
Q

Whether a tall plant from F1 or F2 has TT or Tt composition can be predicted using -

A

Test cross

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19
Q

In a typical test cross ,an organism showing a _____ and whose ____is to be determined , is crossed with the _____ instead of self-crossing

A

Dominant phenotype
Genotype
Recessive parent

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20
Q

Based on his observations on monohybrid cross , Mendel proposed 2 rules to consolidate his understanding of inheritance. These rules are called _____ . Name them .

A

Principles or Laws of Inheritance
1st law -law of inheritance
2nd law - law of segregation

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21
Q

Give the 3 postulates of LAW OF DOMINANCE -

A

1) chars are controlled by discreet units called FACTORS .
2) factors occur in pairs
3) in a dissimilar pair of factors one member if a pair dominates the other .

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22
Q

____law states that the ALLELES do not show any blending and that both the chars are recovered as such in F2 gen , though one of these is not seen at the F1 stage .

A

Law of segregation

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23
Q

Though the parents contain 2 alleles during gamete formation , the factors or alleles of a pair _____ from each other such that a gamete receives only one of the 2 factors .

A

Segregate

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24
Q

Sometimes the F1 had phenotype that did not resemble either of the 2 parents and was in btw the 2 . This phenomenon is called -

A

Incomplete dominance

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25
Q

The inheritance of flower colour in ______is a good example to understand incomplete dominance .

A

Dog flower /snapdragon/ Antirrhinum sp .

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26
Q

Ina cross btw true-breeding red-flower and true-breeding white flower , the ____ generation was ____.

A

The F1 gen

Pink ( all )

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27
Q

When the F1 gen ( all pink ) , were SELF POLLINATED , then F2 resulted in -

A

1 red : 2 pink : 1 white

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28
Q

If we talk about a gene that contains info for producing an enzyme , the modified allele (of the gene) could be responsible for production of -

A

Normal or less efficient enzyme
A non-functional enzyme
No enzyme at all

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29
Q

If the allele produces normal or less efficient enzyme , the modified allele is equivalent to the ____ i.e. , it will produce the ____ i.e., results in the transformation of substrate .

A

Unmodified allele

Same phenotype /trait

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30
Q

The ____allele which represents the original phenotype is the dominant allele and. The __is generally the recessive allele .

A

Unmodified /functioning

Modified

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31
Q

In the enzyme functioning , recessive trait is seen due to ____ or _____ .

A

Non-functional enzyme

Becoz no enzyme is produced

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32
Q

In case of ______, the______ resembles both the parents .

A

Codominance

F1 gen

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33
Q

Examples of codominance -

A

ABO blood grps

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34
Q

ABO blood grps are controlled by the gene ____.

A

I

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35
Q

The ____of the RBCs have _____that protrude from its surface and the _____is controlled by the gene .

A

plasma membrane
Sugar polymers
Kind of sugar

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36
Q

The gene I has __alleles . Name -

A

3
IA
IB
i

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37
Q

The kind of sugar produced by the 3 alleles is -

A

IA ad IB - produce a slightly diff form of sugar

i-does not produce any sugar

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38
Q

When ____and __are present together , they both express their own types of sugars .

A

IA

IB

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39
Q

Becoz of codominance , RBCs have ____types of sugars .

A

Both A and B

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40
Q

A total of ___genotypes of the human ABO blood types are possible .

A

6

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41
Q

ABO blood grouping also provide a good example of ______.

A
Multiple alleles 
(And codominance)
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42
Q

ABO show multiple allelism , becoz ?

A

Here , 3 alleles ( more than 2) are governing the same char .

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43
Q

Since in an individual only 2 alleles can be present , multiple alleles can be found occasionally only when ____are made .

A

Population studies

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44
Q

___is not an autonomous feature of a gene or the product that it has info for .

A

Dominance

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45
Q

Dominance depends as much on the ________and the production of _____.

A

Gene produce

Particular phenotype from this product

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46
Q

Occasionally , a single gene product may produce more than one effect . For example -

A

Starch synthesis in pea seeds -controlled by 1 gene

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47
Q

Starch is synthesised effectively by homozygotes (BB) , therefore ____starch grains are produced . After maturation , BB seeds are rounded and bb wrinkled . B is the dominant allele . But starch grain produce ____ size in Bb .

A

Large

Intermediate size

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48
Q

If starch grain SIZE is considered as the PHENOTYPE , then form this angle , the alleles show _____ .

A

Incomplete dominance ( in size )

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49
Q

When mendel self -hybridised the F1 plants , he found that ____ of F2 had yellow seeds and ____had green seeds. Therefore the yellow and green colour segregated in a _____ratio .

A

3/4th
1/4th
3:1

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50
Q

In a di hybrid cross , the PHENOTYPES round yellow ;wrinkled yellow ;round green ;wrinkled green appeared in the ratio -

A

9:3:3:1

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51
Q

Based on the observations on the di hybrid crosses , mendel proposed a second set of generalizations , that we call -

A

Law of independent assortment

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52
Q

State law of independent assortment -

A

When 2 pairs of traits are combined in a hybrid , segregation of one pair f characters is independent of the other pair of chars .

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53
Q

Mendel published his work on inheritance in ____ , but it remained unrecognised till ____ .

A

1865

1900

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54
Q

Give 3 reasons why mendels work remained unrecognised for several years -

A

1) communication was not easy
2) his concept of genes (or factors ) as stable and discreet units that controlled the expression of traits and of th pair of alleles that did not blend with each other was not accepted by his contemporaries .
3) mendels approach of using maths to explain biology was totally new .

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55
Q

In _____ , 3 scientists ____, ____ and ___ rediscovered mendels results on inheritance of chars .

A

1900
De vries
Correns
Von tschermak

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56
Q

The 3 scientists jointly /independently rediscovered mendels results .

A

Independently

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57
Q

By 1900 , due to advancements in microscopy scientists were able to observe ______ . This led to the discovery of structures in the nucleus that appeared to double and divide just before cell division . They were called _____ .why ?

A

Cell division
Chromosomes / coloured bodies
Becoz they were visualised by staining

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58
Q

B ___ , the chromosome movement during meiosis had been world out .

A

1902

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59
Q

__and ___noted that behaviour of chromosomes was parallel to the behaviour of genes .

A

Walter Sutton

Theodore boveri

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60
Q

Walter Sutton and Theodore boveri used __to explain __.

A

Chromosome movement

Mendels laws

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61
Q

__As well as _____occur in pairs .

A

Chromosomes
Genes
(Sutton and boveri )

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62
Q

The ____ of ___are located on homologous sites on homologous chromosomes .

A

2 alleles

A gene pair

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63
Q

During ____of ____ , the 2 chromosome pairs are aligned at the metaphase plate independently of each other .

A

Anaphase 1

Meiosis 1

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64
Q

___and ___ argued that the pairing and separation of a pair of chromosomes would lead to segregation of a pair of factors they carried .

A

Sutton

Boveri

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65
Q

Sutton united the knowledge of________ with______ principles and called it _______.

A

Chromosomal segregation
Mendelian principles
Chromosomal theory of inheritance

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66
Q

Who gave the chromosomal theory of inheritance ?

A

Sutton

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67
Q

Experimental verification of chromosomal theory of inheritance was done by -

A

Thomas hunt morgan

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68
Q

______led to discovering the basis for VARIATION that sexual reproduction produced .

A

Experimental verification of chromosomal theory of inheritance by Morgan and his colleagues

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69
Q

Morgan worked with the _____flies .

A

Fruit -drosophila melanogaster

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70
Q

Why were fruit flies found very suitable for Morgan’s study ?

A

1) could be grown on simple synthetic medium in the laboratory
2) they complete their life cycle in about 2 weeks
3) a single mating could produce a large number of progeny flies
4) clear differentiation of sexes
5) it has many types of hereditary variations that could be seen with a low power microscope

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71
Q

Morgan carried out several ___ crosses in drosophila to study genes that were ______.

A

Dihybrid

Sex-linked

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72
Q

The crosses carried out by Morgan were similar to the dihybrid crosses carried out by _____ in ____ .

A

Mendel

Peas

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73
Q

Morgan hybridized ____ females to ____males and ____their progeny .

A

Yellow bodied -white eyed females
Brown bodied -red-eyed males
Intercrossed

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74
Q

When Morgan performed the dihybrid cross , he observed that the 2 genes __________ and the F2 ratio deviated very significantly from the ______ .

A

Did not segregate independently of each other ( separated depending on each other )
9:3:3:1 ratio ( expected )

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75
Q

Morgan and his group knew that the genes were located on the _____.

A

X-chromosome

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76
Q

Morgan saw that when the 2 genes were situated on the same chromosome , the proportion of ____Were much higher than the _____ .

A

Parental gene combination

Non-parental type

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77
Q

Morgan coined the term ___ to describe the physical association of genes on chromosomes and the term ____ to describe the NON-PARENTAL gene combinations .

A

Linkage

Recombination

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78
Q

Morgan found that genes __ and __were tightly linked ( on drosophila ) and showed only ___% recombination .

A

White
Yellow
1.3%

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79
Q

Morgan found that ____and __wing were linked more tightly and showed ____% recombination .

A

White
Miniature
37.2%

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80
Q

Who was Morgan’s student ?

A

Alfred sturtevant

81
Q

Alfred sturtevant used the _____betw gene pairs on the ____chromosome as a measure of the ______ and _____their position on the chromosome .

A

Frequency of recombination
Same
Distance btw genes
Mapped

82
Q

Genetic maps were made by -

A

Alfred sturtevant

83
Q

Genetic maps are extensively used as a starting point in the sequencing of whole genomes as was done in the case of the ______ .

A

HGS

Human genome sequencing project

84
Q

Traits that are controlled by one or more GENES are called ____ . For ex -

A

Polygenic traits

Heights / skin colour

85
Q

Besides the involvement of multiple genes , polygenic inheritance also takes into account the influence of ________ .

A

Environment

86
Q

Human skin colour is a classical example of ______.

A

Polygenic inheritance

87
Q

In a polygenic trait , the ___reflects he contribution of each allele i.e., he effect of each allele is ______.

A

Phenotype

Additive

88
Q

As expected ,the genotype with 3 dominant alleles and 3 recessive alleles will have _____skin colour .

A

Intermediate

89
Q

When a single GENE can exhibit multiple phenotypic expression , it is called -

A

Pleiotropic gene

90
Q

The underlying mechanism of pleiotropy is the _________ .

A

Effect of a gene on metabolic pathways which contribute towards diff phenotypes

91
Q

Example of pleiotropy -

A

Disease - phenylketonuria

92
Q

Phenylketonuria is caused by _______ in the gene that codes for ______ . Therefore , it is also called _______.

A

Mutation
Enzyme phenyl alanine hydroxylase
SNGLE GENE MUTATION

93
Q

Single gene mutation in phenylketonuria manifests itself through ______ characterised by _____, ____ and ______ .

A

Phenotypic expression
Mental retardation
Reduction in hair
Skin pigmentation

94
Q

______in the year _____ could trace a specific nuclear structure all through spermatogenesis in a few insects .

A

Henking

1891

95
Q

He king observed that __% of the sperm received this nuclear structure and ___% did not. Receive it . He king called this structure as the _____ .

A

50%
50%
X-body

96
Q

Investigations by other scientists led to he conclusion that the ___ was in fact a chromosome and that is why it was given the name _____.

A

X-body of Henking

X-chromosome

97
Q

It was observed that in a large number of insects , The mechanism of sex-determination is of the _______type .

A

XO type

98
Q

XO type of sex-determination in insects is -

A

Eggs bear an additional X-chromosome besides the autosomes .
Some of the sperms bear the X-chromosome whereas some do not .

99
Q

In insects , eggs fertilized by sperms having an X -chromo become ___ and those fertilised by sperms that do not have X-chromo become ___.

A

Females

Males

100
Q

Due to the involvement of the X- chromo in the determination of sex , it was named __ while the rest of the chromo were named _____ .

A

Sex- chromo

Autosomes

101
Q

_____is an example of XO type of sex deter where males have only one X chromo besides auto but females have a pair of X -chromo .

A

Grasshopper

102
Q

In both humans and insects , __bar 2 types of gametes . Name

A

Males
With or without X-chromo
Some gametes with X and some with Y chromo

103
Q

XO and XY type of sex-determination is designated to be -

A

Male heterogamety

104
Q

In ____ a diff type of sex determination is observed .

A

Birds

105
Q

In birds , the total number of chromo is same for __.

A

Both males and females

106
Q

Female heterogamety is seen in -

A

Birds

107
Q

The female bird has 1___and1___ chromo , whereas the male birds have ___ chromo besides autosomes .

A

Z
W
Pair of Z- chromo

108
Q

____pairs of chromo are exactly same in both males and females .these are the __.

A

22

Autosomes

109
Q

In males , during spermatogenesis . ___types of gametes are produced .

A

2

110
Q

Sex-determination in honey bees is based on the -

A

No of sets of chromosomes an indivisual receives

111
Q

In HONEY BEES ,an offspring formed from the union of sperm and an egg develops as a ___ and an unfertilised egg develops as a ____ by means of _____ .

A

Queen or worker - female
Male -drone
Parthenogenesis

112
Q

Males are __And females are ___ . Ploidy in honeybees

A

Haploid

Diploid

113
Q

Sex- determination in honey bees is called -

A

Haplodiploid sex deter

114
Q

Special feature of haplodiploid sex -determination .

A

Males produce sperms by MITOSIS
Males do not have a father or son
But have a grandfather and grandson

115
Q

Mutation is the phenomenon which results in the alteration of ____and consequently results in changes in the ____and the ____ .

A

DNA sequence
Genotype
Phenotype

116
Q

Loss ( deletion ) or gain (insertion/duplication) of a segment of DNA results in _____ .

A

Alteration in chromosomes

117
Q

Since __Are located on chromosomes , Alteration in chromosomes results in ___or ____.

A

Genes
Abnormalities
Aberrations

118
Q

CHROMOSOMAL ABERRATIONS are commonly observed in ______.

A

Cancer cells -( cancer results due to mutation )

119
Q

Mutation also arises due to change in _____. This is called ____

A

A single base pair of DNA

Point mutation

120
Q

A classical example of point mutation -

A

Sickle cell anemia

121
Q

Deletion and insertion of DNA causes ____.

A

Frame shift mutation

122
Q

CHEMICAL and PHYSICAL factors that induce mutations are called -_____ . Ex -

A

Mutagens

UV rays

123
Q

In human genetics , ____provides a strong tool which is utilised to trace the inheritance of a specific trait , abnormality or disease .

A

Pedigree analysis

124
Q

Broadly , genetic disorders may be grouped into __Categories - ____and ___ .

A

2
Mendelian disorders
Chromosomal disorders

125
Q

_____ disorders are mainly determined by alteration or MUTATION in the SINGLE GENE .

A

Mendelian

126
Q

__disorders are transmitted to the offspring on the same lines as we have studied in the PRINCIPLE OF INHERITANCE .

A

Mendelian

127
Q

The patter of inheritance of MENDELIAN disorders can be traced in a family by the ______ .

A

Pedigree analysis

128
Q

Name some Mendelian disorders -

A
Haemophilia
Cystic fibrosis 
Sickle -cell anaemia 
Colour blindness 
Phenylketonuria 
Thalassemia
129
Q

Mendelian disorders may be _____ or _____ .

A

Dominance

Recessive

130
Q

In _____disorders , the trait may also be linked to the sex-chromosome as in case of ____ .

A

Mendelian

Haemophilia

131
Q

Haemophilia is a __trait and shows transmission from ___to _____ .

A

X-linked recessive
Carrier female
Male progeny

132
Q

Myotonic dystrophy is a __trait .

A

Autosomal dominant - Mendelian

133
Q

Colour blindness is a __disorder .

A

Sex-linked

Recessive

134
Q

Colour blindness is due to _____ CONE of eye resulting in ______ .

A

Red or green

Failure to discriminate but red and green colour

135
Q

Colour blindness is due to ___ in certain genes present not the X-chromo .

A

Mutation

136
Q

Colour blindness occurs in about __% males and __% females .

A

8%

0.4%

137
Q

The gene of colour blindness is ___ . Therefore it is suppressed in females .

A

Recessive

138
Q

Haemophilia is a __ disease .

A

Sex-linked recessive

139
Q

Haemophilia shows transmission from __To ____ .

A

Unaffected carrier female

Some male progeny

140
Q

In haemophilia , a ___ that is a part of ____ involved in ____ is affected .

A

Single protein
Cascade of proteins
Clotting of blood

141
Q

The possibility of a female being haemophilic is extremely rare becoz the -

A

Mother should be at least a carrier and father should be haemophilic

142
Q

The family pedigree of queen victoria shows a number of _____ as she was a carrier of the disease .

A

Haemophilic descendants

143
Q

What happens in haemophilia ?

A

A simple cut may result in non-stop bleeding

144
Q

Sickle cell anaemia is an ___disease .

A

AUTOSOME linked recessive trait

145
Q

When is sickle cell anaemia transmitted from parents to offspring ?

A

When both the parents are carrier for the gene (or heterozygous)

146
Q

Sickle cell anaemia is controlled by _____alleles .

A

SINGLE PAIR of alleles

147
Q

Which pair of allele controls sickle cell a ?

A

Hb-A

Hb-S

148
Q

Out of the __possible genotypes , only the __indivisuals show the diseased phenotype for sickle cell .

A

3

Homozygous for Hb-S (HbS HbS)

149
Q

__indivisuals are apparently unaffected but are carrier for sickle cell as there is ____% probability of transmission of the mutant gene to the progeny .

A

HbA HbS

50%

150
Q

Sickle cell trait is exhibited by HbA HbS indivisuals. T/F

A

T

151
Q

Sickle cell is caused by the substitution of ____ by ___ at the 6th position of ____ of _____molecule. .

A

Glutamic acid
Valine
Beta-globin chain
Haemoglobin molecule

152
Q

The substitution of AMINO ACID in the GLOBIN PROTEIN results due to the _______ at the ____of the BETA GLOBIN GENE from ____to____ .(sickle cell )

A

Single base substitution
6th codon
GAG
GUG

153
Q

In sickle cell , the mutant haemoglobin molecule undergoes _____ under ____causing a change in the shape of the RBC from biconcave disc to ELONGATED sickle like structure .

A

Polymerisation

Low O2 tension

154
Q

Phenylketonuria is an __error of _____ .

A

Inborn

Metabolism

155
Q

Phenylketonuria is an ___trait .

A

Autosomal recessive trait

156
Q

What happens in phenylketonuria ?

A

The affected indivisual lacks an enzyme that converts PHENYLALANINE into TYROSINE

157
Q

The affected indivisual in phenylketonuria lacks an enzyme that coverts __into ____ . As a result ___is accumulated and converted into ____ and _____ .

A
Phenylalanine
Tyrosine
Phenylalanine
Phenylpyruvic acid 
Other derivatives
158
Q

Accumulation of ___in the brain results in _____ in phenylketonuria .

A

Phenylpyruvic acid and other derivatives

Mental retardation

159
Q

In phenylketonuria , ___is excreted through urine becoz of _____.

A

Phenylpyruvic acid

its Poor absorption by kidney

160
Q

Thalassemia is n _____ disease .

A

AUTOSOME linked recessive blood

161
Q

Thalassemia is transmitted from parents to offspring when -

A

Both partners are unaffected carrier for the gene ( or heterozygous)

162
Q

Thalassemia disease is either due to _or _____ which ultimately results in _____ .

A

Mutation
Deletion
Reduced rate of synthesis of ONE of the globin chains (Alpha and beta chains ) that make up haemoglobin molecule

163
Q

Reduced rate of synthesis of one of the globin chains that make up Hb in thalassemia causes -

A

Formation of abnormal Hb molecules resulting into anaemia

164
Q

___ is characteristic of thalasemia disease .

A

Anaemia

165
Q

Thalassemia can be classifies according to___

A

Which chain of Hb molecule is affected

166
Q

In alpha -thalassemia production of ___ is affected while in beta-thalassemia, production of ___is affected .

A

Alpha-globin chain

Beta-globin chain

167
Q

Alpha -thalassemia is controlled by __genes . name -

A

2 closely linked genes

HBA1 HBA2

168
Q

The 2 closely __genes HBA1 and HBA2 are located on chromosome ___of each parent .

A

Linked

16

169
Q

Alpha -thalassemia is observed due to _ or __ of _genes .

A

Deletion
Mutation
One or more of the 4 genes ( HBA1 HBA2 on both parents )

170
Q

The more genes affected in alpha-thalassemia , ____ alpha-globin molecules are produced

A

Less

171
Q

Beta-thalassemia is controlled by __genes . Name -

A

Single

HBB

172
Q

Single gene HBB is located on chromosome __of each parent . Therefore beta-thalassemia occurs due to mutation of _genes .

A

11

One or both

173
Q

That’s semi a is a __problem of synthesizing too few globin molecules while sickle cell is a ___problem of synthesizing an incorrectly functioning globin .

A

Quantitative

Qualitative

174
Q

The chromosomal disorders are caused due to ____.

A

Absence or excess or abnormal arrangement of one or more chromosomes .

175
Q

______duing cell division cycle results in gain or loss of a chromosome .

A

Failure of segregation of chromatids

176
Q

Gain or loss of A CHROMOSOME is -

A

Aneuploidy .

177
Q

Example of aneuploidy -

A

Down’s syndrome - gain in extra copy of chromosome 21

Turner’s syndrome- loss of an X-chromosome

178
Q

___of cell division results in an INC in A WHOLE SET of chromo -

A

Failure of cytokinesis after telophase stage

179
Q

Inc in a whole set of chromo is -

A

Polyploidy

180
Q

Polyploidy is often seen in -

A

Plants

181
Q

Cause of aneuploidy and polyploidy ?

A

aneuploidy - failure of segregation of chromatids - gain/loss of 1 chromo
Polyploidy -failure of cytokinesis - GAIN only of A set of chromo

182
Q

Polyploidy results in a gain or loss of a whole set of chromo .T/F

A

F

Only gain

183
Q

Chromosomal disorders may result due to ___Or _____ do chromo .

A

Monosomy

Trisomy

184
Q

Name a few chromosomal disorders .

A

Down’s
Turner’s
Klinfelter’s

185
Q

The cause of ___is the presence of an additional copy of chromo number 21 (trisomy of 21)

A

Down’s syn

186
Q

Down’s syn was first described by ____ in __year .

A

Langdon down

1866

187
Q

Downs syn is due to an additional copy of chromo __

A

21

188
Q

The affected indivisual in downs is ___ with __head , _____tongue and ____ mouth .

A

Short statured
Small round head
Furrowed tongue
Partially open mouth

189
Q

In downs syn , PALM is ______with characteristic _____ .

A

Broad

Crease

190
Q

___,____and ____development is retarded in downs syn .

A

Physical
Psychomotor
Mental

191
Q

____is caused due to additional copy of X-chromo .

A

Klinefelter’s

192
Q

Klinefelters is due to an additional copy of __chromo resulting into a ___.

A

X-chromo

Karyotype of 47 , XXY

193
Q

Klinfelter indivisual has an overall __Development , however , ___developemnt is also expressed .

A

Masculine

Feminine - development of breast .

194
Q

While feminine character is observed in overall masculine klinfelter person . Name -

A

Development of breast

Gynaecomastia

195
Q

_____is caused due to absence of one of the X-chromo .

A

Turners

196
Q

Turners syn is caused due to ___of ____ . Karyotype of this indivisual is -

A

Absence
X-chromo
45 ,X0

197
Q

Turners syn is seen in ____ and they are sterile as ___Are rudimentary .

A

Females

Ovaries

198
Q

Features of turners .

A

Lack of sec sexual chars

Rudimentary ovaries

199
Q

Characteristics of person with downs syn -

A
Flat back of head
Broad flat fac
Many loops on finger tips
Big and wrinkled tongue
Palm crease 
Congenital heart disease