CBSE 12TH BIOLOGY - Online Test
Q1. Primary consumer category in aquatic &/or terrestrial ecosystem will include :
Answer : Option D
Explaination / Solution:
Primary consumers obtain food from producers or autotrophs. In aquatic ecosystem phytoplankton are main prouder and zooplankton are primary consumers along with frog tadpole , snail and tortoise.
Q2. A company has developed a GM maize plant which produces high amount of sugar. The right granted to the company because of which others cannot use it is
Answer : Option D
Explaination / Solution:
The right granted to the company or organization of which others cannot use it is called biopatent.
A biological patent is a patent on an invention in the field of biology that by law allows the patent holder to exclude others from making, using, selling, or importing the protected invention for a limited period of time.
This right is given as intellectual right to the company.
Q3. Study of human population is called as
Answer : Option A
Explaination / Solution:
The study of human population in a particular area is called demography. It includes the population density, number of male and female individuals and age group of population.
Q4. Main function of pollen tube is to
Answer : Option B
Explaination / Solution:
Pollen tube is formed by germination of pollen grain on stigma of flower. Pollen grain is transferred from stigma to receptive female gametes by pollen tube formed in the style of the pistil.
Q5. Antagonistic interactions will include
Answer : Option D
Explaination / Solution:
Antagonistic interaction will include predation and parasitism in which one species is benefited and other is harmed.
Q6. Heroine is commonly called smack is chemically
Answer : Option A
Explaination / Solution:
Heroine or smack is chemically Diacetylmorphine which is a semi-synthetic opioid. It is the 3,6-diacetyl derivative of morphine (hence diacetylmorphine) and is synthesised from it by acetylation. The white, odourless, bitter crystalline form is commonly the hydrochloride salt, diacetylmorphine hydrochloride. It has a high addiction potential.
Q7. The region of t-RNA which consists of three bases complementary to a mRNA codon is
Answer : Option B
Explaination / Solution:
An anticodon is a unit made up of three nucleotides that correspond to the three bases of the codon on the mRNA. Each tRNA contains a distinct anticodon triplet sequence that can base-pair to one or more codons for an amino acid.
Q8. Agricultural practices of breeding and raising live stock is called
Answer : Option B
Explaination / Solution:
Animal husbandry is the agricultural practice of breeding, feeding and raring of livestock to obtain animals products like milk, eggs etc.
Q9. UNESCO launched biosphere reserve programme under its MAB in :
Answer : Option A
Explaination / Solution:
Launched in 1971, UNESCO's Man and the Biosphere Programme (MAB) is an intergovernmental scientific programme that aims to establish a scientific basis for the improvement of relationships between people and their environment and to protects the endangered species in natural habitat.
Q10. The tissues that allow the penis to fill with blood and become erect is called
Answer : Option D
Explaination / Solution:
Large pockets of erectile tissue in the penis allow it to fill with blood and become erect to increase in size and become turgid during copulation.
