CBSE 12TH BIOLOGY - Online Test
Q1. Breakdown of detritus by microbial enzymes into simple forms is called
Answer : Option D
Explaination / Solution:
Catabolism is the metabolic process due to which mass of the organism reduces. Detritus release microbial enzymes that breakdown the dead or decaying organisms into simpler form.
Q2. Soma clones are obtained by
Answer : Option B
Explaination / Solution:
Genetic engineering is the technique of manipulating the genome of an organism.
The plants produced through genetic engineering technique that are genetically identical to the original plant from which they are produced are called soma clones.
Q3. NWCP stands for
Answer : Option B
Explaination / Solution:
< The Government of India has been implementing the National Wetlands Conservation Programme (NWCP) in close collaboration with the State/UT Governments since the year 1985-86. Under the programme, 115 wetlands have been identified till now by the Ministry which require urgent conservation and management interventions.
The objective of this programme is the conservation of wetlands in the country so as to prevent their further degradation and ensuring their wise use for the benefit of local communities and overall conservation of biodiversity
Q4. The alternation of two different phases of the life cycle involving haploid and diploid stage is called
Answer : Option C
Explaination / Solution:
Alternation of generation is the cyclic change in organisms involving haploid and diploid stages. Meiotic division results into haploid stage and fusion of haploid gametes results into diploid stage.
Q5. Which one is unpaired gland in male reproductive system
Answer : Option D
Explaination / Solution:
Only one Prostate gland is present in male reproductive gland. They release fluid medium in which sperms can move and also provide nutrition to sperms.
Q6. In Mirabilis jalapa when two F1 pink flowered plants were crossed with each other, the F2 generation produced 40 red, 80 pink and 40 white flowering plants. This a case of
Answer : Option D
Explaination / Solution:
F1pink flowered plants are heterozygous. When selfing is done the genotype and phenotype develops as 1:2:1 as 40 red, 80 pink and 40 white flowering plants.
Q7. Which of the followings is mainly produced by the activity of anaerobic bacteria on sewage?
Answer : Option D
Explaination / Solution:
Anaerobic bacteria are used in water treatment process during which marsh gas is produced. This gas have pungent smell and highly flammable.
Q8.
Read the following statements:
i. Based on emission, there are point and diffusion sources of water pollution.
ii. Fertilisers are example of point sources of water pollution.
iii. Industrial discharge pipes are examples of diffusion sources of water pollution.
Answer : Option B
Explaination / Solution:
On the basis of emission of pollutants in water bodies, there are point and diffusion sources of water pollution. Fertilizers are example of diffusion sources of water and industrial discharge pipes are example of point source of water pollution.
Q9. The extraction of DNA from the agrose gel is called as
Answer : Option C
Explaination / Solution:
The extraction of specific bands of DNA from agarose gels in which they are separated through electrophoresis is known as elution. There are many methods for eluting DNA from a piece of agrose.
Q10. According to early Greek thinker unit of life called
Answer : Option D
Explaination / Solution:
According to early Greek thinker units of life called spores. These spores were transferred to different planets including earth.
