CBSE 12TH BIOLOGY - Online Test
Q1. Gel electrophoresis is used for
Answer : Option A
Explaination / Solution:
Gel electrophoresis is used to separate macromolecules like DNA, RNA and proteins. DNA fragments are separated according to their size and proteins can be separated according to their size and their charge (different proteins have different charges) to study the genome of individual organism.
Q2. The embryo development from the somatic cells is called
Answer : Option A
Explaination / Solution:
Embryo develops from the fusion of sperm and ovum. The zygote divides mitotically to form embryo. Sometimes other somatic diploid cells act as embryo. They are called embryoid.
Q3. Assertion: When migration of a section of population to another occurs, gene frequencies change in the original as well as in the population.
Reason: There would be a gene flow if this gene migration happens multiple times.
Reason: There would be a gene flow if this gene migration happens multiple times.
Answer : Option C
Explaination / Solution:
gene flow (also known as gene migration) is the transfer of genetic variation from one population to another. If the rate of gene flow is high enough, then two populations are considered to have equivalent genetic diversity and therefore effectively a single population.
Q4. Female hired to develop the in-vitro fertilized egg of another female to maturity is called
Answer : Option A
Explaination / Solution:
Sometimes egg of female and sperm of male are able to produce but fallopian tube is either blocked or uterus is not capable of implantation. In this case, ovum collected from female and sperm collected from male is fertilized and transferred to another female called surrogate mother for further development.
Q5. For DNA finger printing, the DNA is obtained from
Answer : Option B
Explaination / Solution:
DNA fingerprinting is a method used to identify an individual from a sample of DNA by looking at unique patterns in their DNA.
DNA is extracted from a biological sample. STR analysis is incredibly sensitive so it only needs a tiny amount of someone’s DNA to produce an accurate result. As a result the DNA can be extracted from a wider range of biological samples, including blood, saliva and hair and body secretion etc.
Q6. Which one is not correct about the function of placenta?
Answer : Option A
Explaination / Solution:
Placenta is a tubular structure through which foetus and uterus of mother is connected. It help in transport of nutrition, respiratory gases and release HCG hormones.
Q7. Human being belongs to the species of
Answer : Option A
Explaination / Solution:
Human belongs to a species of Homo sapiens, where Homo represents genus and sapiens represent specific epithet under the class Mammalia.
Q8. The specialized procedure to form an embryo in laboratory in which a sperm is directly injected into the ovum is called
Answer : Option A
Explaination / Solution:
Intra cytoplasmic sperm injection is a specialized procedure to form embryo in laboratory in which a sperm is directly injected into ovum for fertilisation to form zygote.
Q9. Best method to determine paternity is
Answer : Option B
Explaination / Solution:
DNA paternity testing is the most accurate form of paternity testing possible. If DNA patterns between the child and the alleged father do not match on two or more DNA probes, then the alleged father can be totally ruled out. If the DNA patterns between mother, child, and the alleged father match on every DNA probe, the likelihood of paternity is 99.9 percent.
Q10. The type of placenta found in human beings is
Answer : Option B
Explaination / Solution:
Foetus is attached to uterine wall by placenta. It is a disc-shaped having a number of finger-like chorionic villi. This kind of placenta is called discoidal placenta.
