Science (English Medium) इयत्ता १२ - CBSE Question Bank Solutions for Biology

A fruit fly exhibiting both male and female traits is ______.

In a dihybrid cross AABB x aabb, F2 progeny of AABB, AABb, AaBB and AaBb occurs in the ratio of ______.

In a dihybrid cross, F₂ phenotypic ratio is 13 : 3. It is case of ______.

Mendel’s Law of independent assortment holds good for genes situated on the ______.

Two genes ‘A’ and ‘B’ are linked. In a dihybrid cross involving these two genes, the F₁ heterozygote is crossed with homozygous recessive parental type (aa bb). What would be the ratio of offspring in the next generation?

Chargaff’s rules are applicable to ______.

One turn of DNA possesses ______.

If a double stranded DNA has 20% of cytosine, what will be the percentage of adenine in it?

In some viruses, RNA is present instead of DNA indicating that ______.

In a DNA strand the nucleotides are linked together by ______.

A nucleoside differs from a nucleotide. It lacks the ______.

Both deoxyribose and ribose belong to a class of sugars called ______.

The fact that a purine base always paired through hydrogen bonds with a pyrimidine base leads to, in the DNA double helix ______.

Who amongst the following scientists had no contribution in the development of the double helix model for the structure of DNA?

While analysing the DNA of an organism a total number of 5386 nucleotides were found out of which the proportion of different bases were: Adenine = 29%, Guanine = 17%, Cytosine = 32%, Thymine = 17%. Considering the Chargaff’s rule it can be concluded that ______.

What is the nature of the strands of the DNA duplex?

Protein helping in opening of DNA double helix in front of replications fork is ______.

In the F₂ generation of a Mendelian dihybrid cross the number of phenotypes and genotypes are ______.

How far is each base pair from the next one in DNA double helix model?

Synthesis of DNA from RNA is explained by ______.