CBSE 12TH BIOLOGY - Online Test
Q1. Why, according to our reading, did Darwin take so long to publish the Origin of Species?
Answer : Option C
Explaination / Solution:
Charles Darwin knew that once he announced his findings, he would become the center of a debate between religion and science. He knew he would shake everything that people had believed for so long. Darwin waited 20 years to present his work to the public.
Q2. Sparrow is
Answer : Option B
Explaination / Solution:
Sparrow feeds on fruits as well insects. Herbivores or plant eaters are primary consumer and carnivores that feed on herbivores are secondary consumer. So, Sparrow occupy both primary and secondary trophic levels.
Q3. alpha endotoxins are formed by
Answer : Option B
Explaination / Solution:
Alpha endotoxins are formed by sporulation. Alpha endotoxins are known to be frequent contaminants in plasmid DNA extracted from bacteria.
Q4. Lactational amenorrhea method of natural contraception is effective up to
Answer : Option C
Explaination / Solution:
Lactational amenorrhea means absence of menstrual cycle during instance lactational period after the parturition. This method is reported to be useful up to six months of parturition.
Q5. The mature seed that do not contain residual endosperm is called
Answer : Option B
Explaination / Solution:
The mature seeds may contain residual endosperm or get endosperm consumed completely during the embryological development. The seeds without endosperm are called non-albuminous seeds.
Q6. A gut parasite will not need
Answer : Option B
Explaination / Solution:
The parasite obtaintheirfood from host body. Gut parasite like round worm and tap worm absorbed digested food from our body. They do not require alimentary canal as they absorb digested food.
Q7. Select the wrong pair of vegetative propoagules from the following pairs?
Answer : Option B
Explaination / Solution:
The wrong pair of vegetative propoagules is rhizome-potato. Potato is grown vegetatively by eyes present on underground modified tubers. Vegetative propagation is a mode of asexual reproduction.
Q8. If you suspect deficiency of antibodies in a person, to which of the following would you look for confirmatory evidence?
Answer : Option A
Explaination / Solution:
One group of gamma globulins is the immunoglobulins, which are also known as antibodies. The serum globulin electrophoresis test measures the levels of proteins called globulins in the fluid part of a blood sample. This fluid is called serum.
Q9. RNA polymerase is only capable of catalyzing the process of
Answer : Option B
Explaination / Solution:
During protein synthesis, elongation of peptide chain is catalyzed by the enzyme RNA polymerase. Elongation continuous until a non-sense or stop codon is reached.
Q10. Purity of seed is guaranteed by
Answer : Option D
Explaination / Solution:
National Seed Corporation is responsible for maintaining purity of seeds of crop plants. This organization checks the purity of gene from pathogens as well as harmful effect of the contents present in it.
