Principle of inheritance and variation practice · Hard

Sickle cell anaemia is an example of?

Assertion (A): An X-linked recessive trait shows transmission from carrier male to female progeny.

Reason (R): X-linked recessive trait shows non-crisscross inheritance.

In dihybrid experiment on garden peas worked by mendel. What is the $\%$ of yellow round seed:

I. 100% parental combinations are found in ${\mathrm{F}_2}$-generation
II. ${\mathrm{F}_2}$ phenotypic ratio is 3 : 1 in dihybrid cross
III. Dihybrid test cross ratio is 1 : 1 in ${\mathrm{F}_2}$-generation
IV. Linked genes tends to separate frequently
Choose the correct options from the above given statements

$\frac{1}{4}:\frac{1}{2}:\frac{1}{4}$ ratio of TT : Tt : tt can be depicted mathematically binomial expression as (ideally)

Consider a gene that has two alleles and shows complete dominance. When two heterozygotes for this gene breed, they have a $25 \%$ chance of producing a homozygous recessive offspring. The next time they breed, what are the chances that they will once again have a homozygous recessive progeny?

XXY genotype shows:

Genes A, B and C are linked. Genes A and B are more close than A and C. Find out the correct option for the given statements
I. A might be before B and C
II. B might be between A and C
III. C might be between A and B
IV. More crosses has occurred between A and C than A and B

How many gametes can be produced by a diploid organism, if it is heterozygous for 4 loci?

Assertion (A): Multiple alleles can be found only when population studies are made.

Reason (R): Occasionally, a single gene product may produce more than one effect.

How many matching are corrects:

a. Haemophilia - Queen victoria pedigree

b. Phenylketonuria - Inborn error of metabolism

c. Colour blindness - More appears in female than male

d. Sickel cell anaemia - Shape of RBC is biconvex disc

In a mutational event, when adenine is replaced by guanine, it is the case of

Assertion (A): Male and female ratio is almost equal in this world.

Reason (R): Male and female genotype is XX and XY respectively.

A common test to find the genotype of hybrid is by;

Failure of cytokinesis after telophase stage of cell division results in an increase in whole set of chromosomes in an organism__________ phenomenon is

If haploid chromosomal number in a mammal is 24, the monosomic number will be

Consider the following statements about the $A B O$ blood grouping in human beings and select the incorrect pair from the given options

a. ABO blood groups are controlled by gene I, having three alleles $I^A, I^B$ and $i$.

b. $I^A$ and $I^B$ are completely dominant over i but $I^A$ and $I^{\mathrm{B}}$ show incomplete dominance when they are present together

c. The alleles $\mathbf{I}^{\mathrm{A}}$ and $\mathbf{I}^{\mathrm{B}}$ produce almost similar form of sugar but the $\mathrm{i}$ allele produce a completely different sugar

d. A total of six different genotypes and four phenotypes are possible

In a pea plants, yellow seeds are dominant to green. If a heterozygous yellow seeded plant is crossed with a green seeded plant, what ratio of green and yellow seeded plants would you except progeny.

Assertion (A): There are six different combinations or genotypes of the human ABO blood types.

Reason (R): The gene $(I)$ has three alleles $I^A, I^B$ and $I^{O}.$

In rabbit, two recessive genes produce a solid body colour and long hair in contrast to dominant spotted body colour and short hair. The result of a cross between heterozygous spotted short haired rabbit to solid long haired rabbit gives spotted, short haired 48, spotted long haired 5, solid short haired 7, solid long haired 40, total 100. In terms of cross over units, how far are these two genes on the chromosome?

Number of Barr body which will found in case of Turner's
syndrome will be

The reason why some mutations which are harmful do not get eliminated from gene pool is that:

The phenotype of an individual may be affected if the modified allele produces

A. The normal / less efficient enzyme

B. No enzyme at all

C. A non-functional enzyme

Assertion (A): In co-dominance and incomplete dominance, the genotypic & phenotypic ratios are same.

Reason (R): In case of co-dominance the $F_1$ generation resembles both parents.

In Down syndrome:

Assertion: To study mutation, haploids are used.

Reason: Most of the mutations are recessive.

Genetic variation cannot be effectively brought about by

Assertion (A): Gynacomastia is observed in Turner's syndrome.

Reason (R): Such a disorder is caused due to the presence of extra copy of X-chromosome.

Mendel work later formulated into laws of
I. Linkage
II. Segregation
III. Incomplete dominance
IV. Independent assortment
Choose the correct option

What is the probability of production of dwarf offsprings in a cross between two heterozygous tall pea plants.