CBSE 12TH BIOLOGY - Online Test
Q1. In nature, the process by which different organisms evolve similar traits is called
Answer : Option C
Explaination / Solution:
convergent evolution is the process whereby organisms not closely related (not monophyletic), independently evolve similar traits as a result of having to adapt to similar environments or ecological niches.
Analogous organs are example of convergent evolution.
Q2. The average number of children which an average couple has or would have during their life time is called as
Answer : Option B
Explaination / Solution:
Total fertility rate is the average number of children which an average couple has or would have during their life time. It is different form reproductive potential of a healthy female.
Q3. Autoradiogram of VNTR probe gives many band of different size. It differ from individual to individual except
Answer : Option B
Explaination / Solution:
Autoradiogram of VNTR probe gives many band of different size. It differs from individual to individual except monozygotic twins or identical twins Because MZ twins share the same genetic makeup (DNA) because they are formed from a single zygote (fertilized egg).
Q4. What happen during fertilisation after all the sperm reach close to ovum?
Answer : Option A
Explaination / Solution:
Millions of sperms are released during insemination that reaches to ovum for fertilisation. Only one sperm enter the ovum by penetrating the zona pellucida layer of ovum using the enzyme present in its acrosome.
Q5. In the case of peppered moth (Bistonbetularia) the black-coloured form became dominant over the light-coloured form in England during industrial revolution. This is an example of
Answer : Option C
Explaination / Solution:
In England, the places where industrialization is more, peppered moth which was originally white coloured have become dark coloured as dominant due inheritance of darker color character acquired due to the darker environment.
Q6. Now a day, there is less childless couple. This is due to
Answer : Option A
Explaination / Solution:
Some couples are not able to reproduce normally due to malfunctioning of reproductive system. Assisted reproductive technologies can assist them in different way depending upon the need of couple such as IVF, GIFT, ICSI,IUI etc.
Q7. Human genome project can leads to revolutionary new ways to
Answer : Option A
Explaination / Solution:
The Human Genome Project (HGP) is an international thirteen-year project that began on October 1990. It is important because it uses information from DNA to develop new ways to diagnose, treat, cure, or even prevent the thousands of diseases that afflict humankind.
Q8. A Human female reaches menopause around the age of
Answer : Option A
Explaination / Solution:
The stoppage of menstrual cycle in human female is called menopause. This indicates the end of reproductive phase of female at the age of about 50 years.
Q9. Links between organisms that show branching pattern of evolutionary relationships are shown by
Answer : Option B
Explaination / Solution:
Phylogenetic trees shows links between organisms that show branching pattern of evolutionary relationship. In this pattern, the organism that evolves earlier is shown below and further sub branching represent newly evolved organisms.
Q10. High increase in human population is due to
Answer : Option C
Explaination / Solution:
High increase in human population is due to availability of better medical facilities to increase IMR and decrease MMR.
