Recessive character is expressed in
F0
F1
F2
Never expressed.
Our ancestors knew about the inheritance of characters and variations because-
They selectively breed plants and animals and selected for organisms that possessed desirable characters.
They introduced mutations
They performed natural hybridisation
All of the above
Monohybrid cross can be defined as
Cross between plants differing in one chromosome
Cross between plants differing in one character only
Cross between plants differing in two traits
Types of gametes produced by a homozygous parent
many
single type
depends upon number of genes
depends upon number of chromosomes
If a man consists of an extra copy of chromosome number 18, then the condition is known as
Monosomy
Trisomy
Nullisomy
Polyploidy
Disorder caused by the trisomy of chromosome number 21
Klinefelter’s syndrome
Turner’s syndrome
Down’s syndrome
Phenylketonuria
Down’s syndrome was first described in the year
1962
1866
1856
1863
Gynaecomastia refers to
Masculine development in females
Development of breasts in males
Development of female characters in male
Reduced breasts in the female
In humans karyotype of 47, XXY leads to
Edward’s syndrome
Furrowed tongue and partially open mouth are characteristics of
Klinefelter’s syndrome.
n
Column I
Column II
i. Down’s syndrome
a. Broad palm with characteristic palm crease
ii. Klinefelter’s syndrome
b. Gynaecomastia
iii. Turner’s syndrome
c. rudimentary ovaries
d. XO
e. XXY
f. physical development is retarded.
Choose the correct match:
i-c,d; ii-b,e,f; iii-a
i-e,c; ii-b,f; iii-a,d
i-a; ii-b,e,f; iii-c,d
i-a,c; ii-d,e; iii-b,d
Turner’s syndrome is caused by
Absence of Y chromosome
Absence of one of the ‘X’ chromosome
Trisomy of chromosome number 21
Additional copy of chromosome ‘X’.
What will be the ratio of homozygous dominant, homozygous recessive and pure heterozygous traits in F2 generation in pea plant is
1 : 1 : 8
2 : 3 : 2
1 : 1 : 2
2 : 2 : 6
In the results, F2 generation of Mendelian dihybrid cross in pea plant. The ratio of yellow and wrinkled seeded pea plant to the yellow and round seeded pea plant is
1 : 2
1 : 4
1 : 3
3 : 5
Law of Independent Assortment is not applicable to
Linked genes
Genes on different chromosomes
Distantly located gene
both (2) and (3)
Which of the following statement is correct?
Mendel’s work remained unrecognised till 1920.
Mendel’s work suggested that factors were discrete units.
Mendel provided physical proof of the existence of factors.
He used geographical approaches to solve the problems of biology.
Who rediscovered Mendel’s laws?
de Vries
Correns
Von Tschermak
all of these
Pairing and separation of a pair of chromosomes would lead to segregation of a pair of factors they carried. This conclusion was drawn by
Walter Sutton
Theodore Boveri
both (1) and (2)
Thomas Hunt Morgan
Chromosomal theory of inheritance is a combination of
Knowledge of chromosomal segregation with Mendelian principle
Knowledge of Dihybridcross with motion of chromosome
Knowledge of Law of dominance with chromosomal appearance
Knowledge of classical genetics with modern molecular biology
The behaviour of chromosomes and genes can be compared with each other is best explained by which of the following statement?
occur in nucleus
both segregate at the time of gamete formation leading to transmittance of complete pair to a gamete.
Independent pairs( gene) or pair of chromosomes segregate independently of each other or of other pair.
The two alleles of a gene pair are located on homologous site on homologous chromosomes.
The chromosome movement during meiosis have been worked out
1900
1902
1911
1930
Consider the following statement and find out the incorrect one:
Advancement in Microscopy made the study of chromosomal behaviour possible.
Experimental verification of chromosomal theory of Inheritance was done by T. H. Morgan et. Al.
Morgan Chose Drosophila as an experimental animal because it has variations that can be seen with high power of microscope.
Linkage was described by Morgan in Drosophila. Which of the following combinations are correct?
(i) He hybridised yellow bodied, white-eyed females to brown-bodied, red eyed males and then intercrossed their F1
(ii) The ratio of F2 generation is same as that of 9:3:3:1 in this cross.
(iii) The parental combinations are observed more than recombinants.
(iv) According to Morgan Linkage was observed due to chemical association of genes.
(v) All the genes present on same chromosomes have same efficiency to link.
(ii), (iv), (v)
(i), (iii)
(i), (iii), (v)
(i) and (iv)
Boy born to a physically normal couple has been diagnosed with a genetic disorder, this could be
Y- linked trait.
Autosomal dominant trait
X- linkeddominant trait
X- linked recessive trait
Which of the following disorder is associated with Queen Victoria?
Sickle cell anaemia
Haemophilia
Huntington's Disease
Myotonic dystrophy
Which of the following is least probable?
Female child with Sickle cell anaemia
Male child with haemophilia
Carrier female for haemophilia
Female child with haemophilia
Mendel’s success was largely due to his choice of the garden pea plant for his experiments. The advantages of using this plant included:
I. Presence of easily observable contrasting traits for many characters.II. It was possible to control pollination [and hence mating] between different pea plants.III. A large number of seeds could be produced and statistical analysis was therefore more accurate.IV. A long generation time means expression of all traits completely.V. Many observable traits were controlled by single genes.
Only I, II and III
What was the most significant conclusion that Gregor Mendel drew from his experiments with pea plants?
There is considerable genetic variation in garden peas.
Traits are inherited in discrete units, and are not the results of ʺblending.ʺ
Genes are composed of DNA.
An organism that is homozygous for many recessive traits is at a disadvantage.
An organism with two copies of the same allele is:
Homozygous for that trait
Homologous for the allele
Heterozygous for that trait
Heterologous for the allele
Which of the following about the law of segregation is true?
(1) It states that each of two alleles for a given trait segregate into same gametes.
(3) It cn account for the 3:1 ratio seen in the F2 generation of Mendelʹs crosses.
(2) It can e explained by the segregation of heterologous chromosomes during meiosis.
(4) It is a metho that can be used to determine the number of chromosomes in a plant.
Please disable the adBlock and continue. Thank you.
