List of top Questions asked in CBSE CLASS XII

Whose skulls ‘A’, ‘B’, and ‘C’ are shown below? Which of the two are more similar to each other?
Mention what does the dotted line in the graph indicate and state its importance also.
Name the (i) ape-like (ii) man-like primates that existed 1.5 million years ago.
Identify the growth curves ‘A’ and ‘B’.
Name and explain the process the RNA molecule transcribed from 8000 nucleotide-long DNA undergoes to be able to translate a polypeptide of 400 amino acids.
Write the number of RNA polymerases involved in the transcription of DNA in a prokaryote and eukaryotes.
Name this RNA product transcribed from the DNA that subsequently translates into a polypeptide of 400 amino acids. Mention the enzyme responsible for transcribing this type of RNA from the DNA.
Studying Diseases:
Name the human body organ affected by the consumption of these drugs.
Production of Biological Products:
Name ‘A’ and ‘B’ fragments.
How are such drugs consumed?
Chemical Safety Testing:
Where does EcoRI cut the palindrome? Write the events followed thereafter to form a recombinant DNA.
Write the ‘palindrome’ recognized by EcoRI.
Differentiate between grazing food chain and detritus food chain.
Name any two hotspots in India.
Name the group of drugs whose skeletal molecule is shown below:
Study the graph given below that represents the changes in the thickening of the uterine wall in women ‘X’ and women ‘Y’ over a period of one month:
What does the graph with respect to women ‘X’ and woman ‘Y’ indicate? Give a suitable reason.
Draw a well-labelled diagram of the sectional view of a male gametophyte/microspore of an angiosperm and write the functions of any two parts labelled. (Any four labels).
Explain Brood parasitism with the help of a suitable example.
Assertion (A): Plasmids are autonomously replicating circular extra-chromosomal DNA.
Reason (R): Plasmids are usually present in eukaryotic cells.
Assertion (A): Some aquatic ecosystems have inverted biomass pyramids.
Reason (R): More energy is required by organisms occupying higher trophic levels.
What is artificial insemination in ART? Under what conditions is the person medically advised to go for it?
Why does a patient of ADA-deficiency require repeated infusions of genetically engineered lymphocytes? Suggest a possible permanent remedy.