List of top Questions asked in Maharashtra Board Class XII Exam

Explain the greenhouse effect with reference to gases responsible for it and their sources.
What are the limitations of the root pressure theory?

Identify A, B, and C from the above diagrams and give their functions. 


 

Explain different steps involved in the PCR technique.
Name and describe hormones secreted by ovaries.
Explain unique features of acquired immunity.
What is reproductive isolation? Describe any two types each of pre-mating and post-mating isolating mechanisms.
Give the different steps involved in the formation of mRNA from hnRNA.
Explain the steps involved in the preliminary treatment of sewage.

Select and rewrite the appropriate disorder of the respiratory system based on the given symptoms: 
Given disorders: \[ {[ Sinusitis, Emphysema, Silicosis and Asbestosis, Laryngitis ]} \]
(a) Breakdown of alveoli, shortness of breath.
(b) Inflammation of the sinuses, mucous discharge.
(c) Inflammation of larynx, vocal cords, sore throat, hoarseness of voice, mucous build-up,
and cough.
(d) Inflammation of fibrosis, lung damage.

What is differentiation and redifferentiation?
Explain factors affecting water absorption.
Describe mutualism.

Identify and define ‘A’ and ‘B’ in relation to the uptake of water by the root: 

What are the significances of double fertilization?

Define the following terms: 
(a) Gene Flow 
(b) Chromosomal Aberrations

Enlist the uses of gene therapy.
Distinguish between human sperm and ovum.

Observe the graph and select the correct option: 

Arrange the following steps of DNA fingerprinting in correct sequence: 
(a) Gel electrophoresis (b) Isolation of DNA (c) Southern blotting (d) Restriction digestion

What are the reasons for the success of Mendel?
Explain the term Emigration.
How many meiotic divisions are required for the formation of 300 seeds in angiosperm?
Which cells of islets of Langerhans produce the hormone insulin?
Give the name of the microbial source of the antibiotic chloromycetin.