Principles of Inheritance and Variation PYQ — Page 8

Nicotiana sylvestris flowers only during long days and N.tabacum flowers only during short days. If raised in the laboratory under different photoperiods, they can be indued to flower at the same time and can be cross-fertilized to produce self-fertile offspring. What is the best reason considering $N$. sylvestris and N.tabocum to be separate species ?

In Drosophila, the sex is determined by,

When a cluster of genes show linkage behaviour they:

Which one of the following conditions though harmful in itself, is also potential saviour from a mosquito borne infectious disease?

Two crosses between the same pair of genotypes or phenotypes in which the sources of the gametes arc reversed in one cross, is known as:

Pattern baldness, moustaches and beard in human males are examples of:

What would happen if in a gene encoding a polypeptide of 50 amino acids, $25^{\text {th }}$ codon (UAU) is mutated to UAA?

Christmas disease is another name for

Which one of the following traits of garden pea studied by Mendel was a recessive feature?

The genes controlling the seven pea characters studied by Mendel are now known to the located on how many different chromosomes?

Which one of the following discoveries resulted in a Nobel Prize?

Down's syndrome is caused by an extra copy of chromosome number 21. What percentage of offspring produced by an affected mother and a normal father would be affected by this disorder?

The linkage map of $\mathrm{X}$-chromosome of fruitfly 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:

Genes for cytoplasmic male sterility in plants are generally located in:

A plant is of $F_1$ generation with genotype "AABbCC". On selfing of this plant what is the phenotypic ratio in $\mathrm{F}_2$ generation?

Change in the sequence of nucleotide in DNA is called as:

Which of the following is the example of sex-linked disease?

Reason of fast speciation in present-day crop plants is:

Sequence of which of the following is used to know the phylogeny?

Which of the following is a correct match?

There are three genes $\mathrm{a}, \mathrm{b}$ and $\mathrm{c}$. The percentage of crossing over between $a$ and $b$ is $20 \%, b$ and $c$ is $28 \%$ and $a$ and $c$ is $8 \%$. What is the sequence of genes on chromosome?

A diseased man marries a normal woman. They get three daughter and five sons. All the daughter were diseased and sons were normal. The gene of this disease is:

A gene is said to be dominant if:

Which of the following is the example of pleiotropic gene?