The regulatory genes are located [Kerala CET 2003]

Along with the structural genes

In between operator and the structural genes

In the middle of structural genes

In Operon concept, the regulator gene regulates chemical reactions in the cell by [AIIMS 1985]

Inhibiting transcription of mRNA

Inactivating enzymes in the reaction

Inhibiting transcription of mRNA

Inhibiting migration of mRNA into cytoplasm

Inhibiting the substrate in the reaction

Biological marriage of one of the following should be avoided [BHU 1982, 84, 85; AFMC 1984, 95, 2001; CPMT 1976, 84, 85, 90;] or After examining the blood groups of a couple, the doctor advised them not to have more than one child. The blood group of the couple are likely to be [AIIMS 1983; CBSE PMT 1990, 02; MP PMT 1990, 95, 2000, 03; AIEEE 2003]

\[R{{h}^{+}}\]male and \[R{{h}^{+}}\] female

\[R{{h}^{+}}\]male and \[R{{h}^{-}}\]female

\[R{{h}^{+}}\]male and \[R{{h}^{+}}\] female

\[R{{h}^{-}}\]male and \[R{{h}^{+}}\] female

\[R{{h}^{-}}\]male and \[R{{h}^{-}}\] female

A recessive gene is one which

Occurs less frequently than a dominant one

In man sexlinked characters are mainly transmitted through [MP PMT 2004]

X-chromosome, Y-chromosome and Autosomes

Whereas the number of chromosomes is reduced to half in first reduction division of meiosis, then what is the need for second mitotic division[MP PMT 2001]

For equal distribution of haploid chromosomes

For the segregation of replicated chromosomes

For equal distribution of haploid chromosomes

For the formation of four gametes

For equal distribution of genes on chromosomes

Tizo and Levan's contribution is very significant because they [CBSE PMT 1993]

Gave the number of human chromosomes

The salivary gland chromosomes in the dipteran larvae, are useful in gene mapping because [CBSE PMT 2005]

They have endoreduplicated chromosomes

Diameter of each nucleosome is about

\[200\overset{\text{o}}{\mathop{\text{A}}}\,\]

\[50\overset{\text{o}}{\mathop{\text{A}}}\,\]

\[110\overset{\text{o}}{\mathop{\text{A}}}\,\]

\[200\overset{\text{o}}{\mathop{\text{A}}}\,\]

\[400\overset{\text{o}}{\mathop{\text{A}}}\,\]

Assertion : Agrobacterium tumefaciens is popular in genetic engineering because this bacterium is associated with the roots of all cereal and pulse crops. [AIIMS 2005] Reason : A gene incorporated in the bacterial chromosomal genome gets automatically transferred to the crop with which the bacterium is associated.

If the assertion is false but reason is true

If both the assertion and the reason are true and the reason is a correct explanation of the assertion

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

If the assertion is true but the reason is false

If both the assertion and reason are false

If the assertion is false but reason is true

Assertion : If pollen mother cells has 42 chromosomes. The pollen has only 21 chromosomes. Reason : Pollens are formed after meiosis in pollen mother cell. [AIIMS 1997]

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

If both the assertion and the reason are true and the reason is a correct explanation of the assertion

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

If the assertion is true but the reason is false

If both the assertion and reason are false

If the assertion is false but reason is true

Assertion : Haemophilia never occurs in women. Reason : Gene for haemophilia is located on X chromosome. [AIIMS 1994, 96]

If both the assertion and reason are false

If both the assertion and the reason are true and the reason is a correct explanation of the assertion

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

If the assertion is true but the reason is false

If both the assertion and reason are false

If the assertion is false but reason is true

Assertion : Translocations may not involve a loss or an addition of chromosome. Reason : During translocation a part of a chromosome becomes detached and joins a part of a nonhomologous chromosome.

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

If both the assertion and the reason are true and the reason is a correct explanation of the assertion

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

If the assertion is true but the reason is false

If both the assertion and reason are false

If the assertion is false but reason is true

Assertion : Human chromosomes have been studied through banding technique. Reason : Banding technique is useful in studying chromosomal aberrations.

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

If both the assertion and the reason are true and the reason is a correct explanation of the assertion

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

If the assertion is true but the reason is false

If both the assertion and reason are false

If the assertion is false but reason is true

Assertion : Cytoplasmic inheritance occurs only due to plasmagenes. Reason : Plasmagenes are restricted to only two cell organelles i.e., mitochondria and chloroplast.

If both the assertion and reason are false

If both the assertion and the reason are true and the reason is a correct explanation of the assertion

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

If the assertion is true but the reason is false

If both the assertion and reason are false

If the assertion is false but reason is true

Assertion : Allosomes determine sex of individual. Reason : Androsomes are responsible for female sex.

If both the assertion and reason are false

If both the assertion and the reason are true and the reason is a correct explanation of the assertion

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

If the assertion is true but the reason is false

If both the assertion and reason are false

If the assertion is false but reason is true

Assertion : In prokaryotes, there are three initiation factors used for protein synthesis. Reason : All the initiation factors have their own functions.

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

If both the assertion and the reason are true and the reason is a correct explanation of the assertion

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

If the assertion is true but the reason is false

If both the assertion and reason are false

If the assertion is false but reason is true

Assertion : The genetic codes are commaless. Reason : Genetic codes are overlapping.

If both the assertion and reason are false

If both the assertion and the reason are true and the reason is a correct explanation of the assertion

If both the assertion and reason are true but the reason is not a correct explanation of the assertion

If the assertion is true but the reason is false

If both the assertion and reason are false

If the assertion is false but reason is true

302 + Mcqs in Genetics in Biology Page 6 McqOptions

251.	The regulatory genes are located [Kerala CET 2003]
A.	Along with the structural genes
B.	In between operator and the structural genes
C.	In the middle of structural genes
D.	At the end of structural genes
Answer» E.

Discussion

252.	Functioning of structural genes is controlled by [MP PMT 2001]
A.	Operator
B.	Promoter
C.	Ligase
D.	Regulatory gene
Answer» B. Promoter

Discussion

253.	In Operon concept, the regulator gene regulates chemical reactions in the cell by [AIIMS 1985]
A.	Inactivating enzymes in the reaction
B.	Inhibiting transcription of mRNA
C.	Inhibiting migration of mRNA into cytoplasm
D.	Inhibiting the substrate in the reaction
Answer» B. Inhibiting transcription of mRNA

Discussion

254.	A husband and wife have normal vision but fathers of both of them were colour blind. Probability of their first daughter to be colour blind is [CBSE PMT 1990]
A.	0.25
B.	0.5
C.	0.75
D.	0
Answer» E.

Discussion

255.	How many different types of gametes canbe formed by \[{{F}_{1}}\] progeny, resulting from the following cross: AA BB CC × aa bb cc [AIIMS 2004]
A.	3
B.	8
C.	27
D.	64
Answer» C. 27

Discussion

256.	Pure homozygous offsprings in a dihybrid cross in the generation will be
A.	1/2
B.	1/4
C.	1/8
D.	1/16
Answer» D. 1/16

Discussion

257.	Each chromosoxme at the anaphase stage of a bone marrow cell in our body has [CBSE PMT 1995]
A.	Two chromatids
B.	No chromatids
C.	Only one chromatid
D.	Several chromatids
Answer» B. No chromatids

Discussion

258.	In Drosophila melanogaster, 3 pairs of autosomes and sex chromosomes of XO type give rise to a normal male in appearance. In man, 22 pairs of autosomes and XO type of sex chromosomes form [MP PMT 1994]
A.	Normal female
B.	Normal male
C.	Klinefelter's syndrome
D.	Turner's syndrome
Answer» E.

Discussion

259.	In man the mutation disease, aniridia (congenital absence of iris) occurs due to [BHU 1988]
A.	Dominant mutation
B.	Recessive mutation
C.	Lethal mutation
D.	Iso-alleles
Answer» B. Recessive mutation

Discussion

260.	Between persons of which two blood groups is the blood transfusion not possible [MP PMT 1992]
A.	O and AB (AB recipient)
B.	O and A (O donor)
C.	O and B (O donor)
D.	O and AB (AB donor)
Answer» E.

Discussion

261.	Biological marriage of one of the following should be avoided [BHU 1982, 84, 85; AFMC 1984, 95, 2001; CPMT 1976, 84, 85, 90;] or After examining the blood groups of a couple, the doctor advised them not to have more than one child. The blood group of the couple are likely to be [AIIMS 1983; CBSE PMT 1990, 02; MP PMT 1990, 95, 2000, 03; AIEEE 2003]
A.	\[R{{h}^{+}}\]male and \[R{{h}^{-}}\]female
B.	\[R{{h}^{+}}\]male and \[R{{h}^{+}}\] female
C.	\[R{{h}^{-}}\]male and \[R{{h}^{+}}\] female
D.	\[R{{h}^{-}}\]male and \[R{{h}^{-}}\] female
Answer» B. \[R{{h}^{+}}\]male and \[R{{h}^{+}}\] female

Discussion

262.	During transcription holoenzyme RNA polymerase binds to a DNA sequence and the DNA assumes a saddle like structure at the point. What is that sequence called [CBSE PMT 2005]
A.	CAAT box
B.	GGTT box
C.	AAAT box
D.	TATA box
Answer» E.

Discussion

263.	RNA polymerase is involved in [CPMT 2003]
A.	Translation
B.	Transcription
C.	Translocation
D.	Replication
Answer» C. Translocation

Discussion

264.	RR (Red) is crossed with ww (white), all the Rw offsprings are pink. This is an indication that R gene is [CPMT 1974, 76, 81]
A.	Hybrid
B.	Recessive
C.	Incompletely dominant
D.	Mutant
Answer» D. Mutant

Discussion

265.	A recessive gene is one which
A.	Occurs less frequently than a dominant one
B.	Occurs only in heterozygotes
C.	Produces large amounts of RNA
D.	Produces very less or no mRNA
Answer» E.

Discussion

266.	Mendel's law were first published in the year
A.	1875
B.	1890
C.	1928
D.	1866
Answer» E.

Discussion

267.	"Nu body'' was shown by [BVP 2003]
A.	Darlington
B.	Johanssen
C.	Woodcock
D.	Temin and Baltimore
Answer» D. Temin and Baltimore

Discussion

268.	Percentage of recombination between A and B is 9% and C is 17%, B and C is 26%, then the arrangement of genes is [Orissa JEE 2004]
A.	ABC
B.	ACB
C.	BCA
D.	BAC.
Answer» E.

Discussion

269.	Number of autosomes in human sperm is [CPMT 1983, 84; DPMT 1985; MP PMT 2003]
A.	11
B.	22
C.	44
D.	45
Answer» C. 44

Discussion

270.	At a particular locus, frequency of 'A' allele is 0.6 and that of 'a' is 0.4. What would be the frequency of heterozygotes in a random mating population of equilibrium [CBSE PMT 2005]
A.	0.16
B.	0.48
C.	0.36
D.	0.24
Answer» E.

Discussion

271.	In man sexlinked characters are mainly transmitted through [MP PMT 2004]
A.	Y-chromosome
B.	Autosomes
C.	X-chromosome
D.	X-chromosome, Y-chromosome and Autosomes
Answer» D. X-chromosome, Y-chromosome and Autosomes

Discussion

272.	The linkage map of X-chromosome of fruit fly has 66 units with yellow body gene (y) at one end and bobbed hair (b) gene at the other end. The recombination frequency between these two genes (y and b) should be [CBSE PMT 2003]
A.	1
B.	0.66
C.	0.5
D.	0.055
Answer» C. 0.5

Discussion

273.	Whereas the number of chromosomes is reduced to half in first reduction division of meiosis, then what is the need for second mitotic division[MP PMT 2001]
A.	For the segregation of replicated chromosomes
B.	For equal distribution of haploid chromosomes
C.	For the formation of four gametes
D.	For equal distribution of genes on chromosomes
Answer» B. For equal distribution of haploid chromosomes

Discussion

274.	Lampbrush chromosomes are found inside [CPMT 1999; MP PMT 2002]
A.	Salivary glands of Drosophila
B.	Salivary glands of silk moth
C.	Oocytes of frog
D.	Nucleus of man
Answer» D. Nucleus of man

Discussion

275.	Number of autosomes in a normal female is [CPMT 1995]
A.	21
B.	22
C.	23
D.	44
Answer» E.

Discussion

276.	The sum of genes in a population is called [CPMT 1993]
A.	Genotype
B.	Karyotype
C.	Gene pool
D.	Lethal gene
Answer» D. Lethal gene

Discussion

277.	A study of heredity and hereditary character is called as [CPMT 1978]
A.	Genetics
B.	Eugenics
C.	Euthenics
D.	Cytology
Answer» B. Eugenics

Discussion

278.	Tizo and Levan's contribution is very significant because they [CBSE PMT 1993]
A.	Gave the number of human chromosomes
B.	Pointed out mutational changes
C.	Identified Barr bodies
D.	Detected sex linkage
Answer» B. Pointed out mutational changes

Discussion

279.	Gene can be defined as [AFMC 1991]
A.	Unit of segregation
B.	Unit of physiological activity
C.	Unit of recombination
D.	Unit of function
Answer» D. Unit of function

Discussion

280.	The genes, which are confined to differential region of Y chromosome only, are called [AIIMS 1998; MP PMT 2000; CBSE PMT 1994; CPMT 2003]
A.	Mutant
B.	Autosomal
C.	Holandric
D.	Completely sex-linked
Answer» D. Completely sex-linked

Discussion

281.	The human chromosomes are divided into 7 groups, B-chromosomes are
A.	6-12
B.	1-2
C.	13-15
D.	4-5
Answer» E.

Discussion

282.	The salivary gland chromosomes in the dipteran larvae, are useful in gene mapping because [CBSE PMT 2005]
A.	These are fused
B.	These are much longer in size
C.	These are easy to stain
D.	They have endoreduplicated chromosomes
Answer» E.

Discussion

283.	Which organism was used by Beadle and Tatum to proposed one gene-one enzyme hypothesis [CPMT 2004]
A.	E.coli
B.	Nostoc
C.	Drosophila
D.	Neurospora
Answer» E.

Discussion

284.	Octamer which form complex unit with DNA is called
A.	Nucleosome
B.	Centrosome
C.	Chromosome
D.	Endosome
Answer» B. Centrosome

Discussion

285.	Genetically active area of chromosome is called [BVP 2000]
A.	Euchromatin
B.	Heterochroatin
C.	Heptan
D.	Cistron
Answer» B. Heterochroatin

Discussion

286.	Different types of chromosomes can be recognised by the position of the following separating the two arms [KCET 1994]
A.	Centromere
B.	Genes
C.	Spindle
D.	Nucleus
Answer» B. Genes

Discussion

287.	Genes are [MP PMT 2005]
A.	Morphological units
B.	Hereditary units
C.	Functional units
D.	All units
Answer» C. Functional units

Discussion

288.	An unfertilized human egg contains [CPMT 1979, 93; Manipal 1995; MP PMT 2000]
A.	Two X chromosomes
B.	One X and Y chromosome
C.	One Y chromosome only
D.	One X chromosome only
Answer» E.

Discussion

289.	In which bacteria insulin gene was cloned
A.	Klebsiella
B.	E. coli
C.	Shigella
D.	Clostridium
Answer» C. Shigella

Discussion

290.	Diameter of each nucleosome is about
A.	\[50\overset{\text{o}}{\mathop{\text{A}}}\,\]
B.	\[110\overset{\text{o}}{\mathop{\text{A}}}\,\]
C.	\[200\overset{\text{o}}{\mathop{\text{A}}}\,\]
D.	\[400\overset{\text{o}}{\mathop{\text{A}}}\,\]
Answer» C. \[200\overset{\text{o}}{\mathop{\text{A}}}\,\]

Discussion

291.	The haploid condition is found in [NCERT 1982; CPMT 1984]
A.	Amoeba
B.	Bacteria
C.	Ovum
D.	Zygote
Answer» D. Zygote

Discussion

292.	Assertion : Agrobacterium tumefaciens is popular in genetic engineering because this bacterium is associated with the roots of all cereal and pulse crops. [AIIMS 2005] Reason : A gene incorporated in the bacterial chromosomal genome gets automatically transferred to the crop with which the bacterium is associated.
A.	If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B.	If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C.	If the assertion is true but the reason is false
D.	If both the assertion and reason are false
E.	If the assertion is false but reason is true
Answer» E. If the assertion is false but reason is true

Discussion

293.	Assertion : If pollen mother cells has 42 chromosomes. The pollen has only 21 chromosomes. Reason : Pollens are formed after meiosis in pollen mother cell. [AIIMS 1997]
A.	If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B.	If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C.	If the assertion is true but the reason is false
D.	If both the assertion and reason are false
E.	If the assertion is false but reason is true
Answer» B. If both the assertion and reason are true but the reason is not a correct explanation of the assertion

Discussion

294.	Assertion : Haemophilia never occurs in women. Reason : Gene for haemophilia is located on X chromosome. [AIIMS 1994, 96]
A.	If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B.	If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C.	If the assertion is true but the reason is false
D.	If both the assertion and reason are false
E.	If the assertion is false but reason is true
Answer» D. If both the assertion and reason are false

Discussion

295.	Assertion : Translocations may not involve a loss or an addition of chromosome. Reason : During translocation a part of a chromosome becomes detached and joins a part of a nonhomologous chromosome.
A.	If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B.	If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C.	If the assertion is true but the reason is false
D.	If both the assertion and reason are false
E.	If the assertion is false but reason is true
Answer» B. If both the assertion and reason are true but the reason is not a correct explanation of the assertion

Discussion

296.	Assertion : Human chromosomes have been studied through banding technique. Reason : Banding technique is useful in studying chromosomal aberrations.
A.	If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B.	If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C.	If the assertion is true but the reason is false
D.	If both the assertion and reason are false
E.	If the assertion is false but reason is true
Answer» B. If both the assertion and reason are true but the reason is not a correct explanation of the assertion

Discussion

297.	Assertion : Cytoplasmic inheritance occurs only due to plasmagenes. Reason : Plasmagenes are restricted to only two cell organelles i.e., mitochondria and chloroplast.
A.	If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B.	If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C.	If the assertion is true but the reason is false
D.	If both the assertion and reason are false
E.	If the assertion is false but reason is true
Answer» D. If both the assertion and reason are false

Discussion

298.	Assertion : Allosomes determine sex of individual. Reason : Androsomes are responsible for female sex.
A.	If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B.	If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C.	If the assertion is true but the reason is false
D.	If both the assertion and reason are false
E.	If the assertion is false but reason is true
Answer» D. If both the assertion and reason are false

Discussion

299.	Assertion : In prokaryotes, there are three initiation factors used for protein synthesis. Reason : All the initiation factors have their own functions.
A.	If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B.	If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C.	If the assertion is true but the reason is false
D.	If both the assertion and reason are false
E.	If the assertion is false but reason is true
Answer» B. If both the assertion and reason are true but the reason is not a correct explanation of the assertion

Discussion

300.	Assertion : The genetic codes are commaless. Reason : Genetic codes are overlapping.
A.	If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B.	If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C.	If the assertion is true but the reason is false
D.	If both the assertion and reason are false
E.	If the assertion is false but reason is true
Answer» D. If both the assertion and reason are false

Discussion

Explore topic-wise MCQs in Biology.

The regulatory genes are located [Kerala CET 2003]

Functioning of structural genes is controlled by [MP PMT 2001]

In Operon concept, the regulator gene regulates chemical reactions in the cell by [AIIMS 1985]

A husband and wife have normal vision but fathers of both of them were colour blind. Probability of their first daughter to be colour blind is [CBSE PMT 1990]

How many different types of gametes canbe formed by \[{{F}_{1}}\] progeny, resulting from the following cross: AA BB CC × aa bb cc [AIIMS 2004]

Pure homozygous offsprings in a dihybrid cross in the generation will be

Each chromosoxme at the anaphase stage of a bone marrow cell in our body has [CBSE PMT 1995]

In Drosophila melanogaster, 3 pairs of autosomes and sex chromosomes of XO type give rise to a normal male in appearance. In man, 22 pairs of autosomes and XO type of sex chromosomes form [MP PMT 1994]

In man the mutation disease, aniridia (congenital absence of iris) occurs due to [BHU 1988]

Between persons of which two blood groups is the blood transfusion not possible [MP PMT 1992]

During transcription holoenzyme RNA polymerase binds to a DNA sequence and the DNA assumes a saddle like structure at the point. What is that sequence called [CBSE PMT 2005]

RNA polymerase is involved in [CPMT 2003]

RR (Red) is crossed with ww (white), all the Rw offsprings are pink. This is an indication that R gene is [CPMT 1974, 76, 81]

A recessive gene is one which

Mendel's law were first published in the year

"Nu body'' was shown by [BVP 2003]

Percentage of recombination between A and B is 9% and C is 17%, B and C is 26%, then the arrangement of genes is [Orissa JEE 2004]

Number of autosomes in human sperm is [CPMT 1983, 84; DPMT 1985; MP PMT 2003]

At a particular locus, frequency of 'A' allele is 0.6 and that of 'a' is 0.4. What would be the frequency of heterozygotes in a random mating population of equilibrium [CBSE PMT 2005]

In man sexlinked characters are mainly transmitted through [MP PMT 2004]

The linkage map of X-chromosome of fruit fly has 66 units with yellow body gene (y) at one end and bobbed hair (b) gene at the other end. The recombination frequency between these two genes (y and b) should be [CBSE PMT 2003]

Whereas the number of chromosomes is reduced to half in first reduction division of meiosis, then what is the need for second mitotic division[MP PMT 2001]

Lampbrush chromosomes are found inside [CPMT 1999; MP PMT 2002]

Number of autosomes in a normal female is [CPMT 1995]

The sum of genes in a population is called [CPMT 1993]

A study of heredity and hereditary character is called as [CPMT 1978]

Tizo and Levan's contribution is very significant because they [CBSE PMT 1993]

Gene can be defined as [AFMC 1991]

The genes, which are confined to differential region of Y chromosome only, are called [AIIMS 1998; MP PMT 2000; CBSE PMT 1994; CPMT 2003]

The human chromosomes are divided into 7 groups, B-chromosomes are

The salivary gland chromosomes in the dipteran larvae, are useful in gene mapping because [CBSE PMT 2005]

Which organism was used by Beadle and Tatum to proposed one gene-one enzyme hypothesis [CPMT 2004]

Octamer which form complex unit with DNA is called

Genetically active area of chromosome is called [BVP 2000]

Different types of chromosomes can be recognised by the position of the following separating the two arms [KCET 1994]

Genes are [MP PMT 2005]

An unfertilized human egg contains [CPMT 1979, 93; Manipal 1995; MP PMT 2000]

In which bacteria insulin gene was cloned

Diameter of each nucleosome is about

The haploid condition is found in [NCERT 1982; CPMT 1984]

Assertion : If pollen mother cells has 42 chromosomes. The pollen has only 21 chromosomes. Reason : Pollens are formed after meiosis in pollen mother cell. [AIIMS 1997]

Assertion : Haemophilia never occurs in women. Reason : Gene for haemophilia is located on X chromosome. [AIIMS 1994, 96]

Assertion : Translocations may not involve a loss or an addition of chromosome. Reason : During translocation a part of a chromosome becomes detached and joins a part of a nonhomologous chromosome.

Assertion : Human chromosomes have been studied through banding technique. Reason : Banding technique is useful in studying chromosomal aberrations.

Assertion : Cytoplasmic inheritance occurs only due to plasmagenes. Reason : Plasmagenes are restricted to only two cell organelles i.e., mitochondria and chloroplast.

Assertion : Allosomes determine sex of individual. Reason : Androsomes are responsible for female sex.

Assertion : In prokaryotes, there are three initiation factors used for protein synthesis. Reason : All the initiation factors have their own functions.

Assertion : The genetic codes are commaless. Reason : Genetic codes are overlapping.