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

How does a degenerate code differ from an unambiguous one?

Write the scientific name of the source plant and the part from which opiods are extracted. What is it commonly and chemically called?

Where in the human body are its specific receptors located ? How do opioids affect the human body ?

Answer the following question.
Describe the structure and function of a t-RNA molecule. Why is it referred to as an adapter molecule?

Anticodon is an unpaired triplet of bases in an exposed position of ______.

Amino acid acceptor end of tRNA lies at ______.

Which RNA carries the amino acids from the amino acid pool to mRNA during protein synthesis?

Enumerate four most common warning signs of drug and alcohol abuse amongst the youth.

Which one of the following is a stop codon?

(a) UAG

(b) UAC

(c) AUG

(d) UCA

What is apomixis?

List two essential roles of ribosomes during translation.

Briefly describe the following:

Translation

Do you think that friends can influence one to take alcohol/drugs? If yes, how may one protect himself/herself from such an influence?

In your view, what motivates youngsters to take to alcohol or drugs and how can this be avoided?

Under polio prevention programme, infants in India were given polio vaccines on a large scale at regular intervals to eradicate polio from the country.

(a) What is a vaccine? Explain how does it impart immunity to the child against the disease.
(b) With the help of an example each, differentiate between active and passive immunity.

Name the pattern of inheritance where F₁ phenotype

resembles only one of the two parents.

The process of translation is ______.

The translation termination triplet is ______.

The three codons which result in the termination of polypeptide chain synthesis are ______.

During translation, activated amino acids get linked to tRNA. This process is commonly called as ______.