CBSE 12TH BIOLOGY - Online Test
Q1. Five oogonia yield 10 primary oocytes, then how many ova are produced on completion of oogenesis?
Answer : Option B
Explaination / Solution:
Each oogonium produces one ovum at the end of oogenesis process and three polar bodies. Thus, five oogonia will produce five ova at the completion of oogenesis process.
Q2. Jhum cultivation refers to
Answer : Option A
Explaination / Solution:
Jhum cultivation refers to tribal method of shifting cultivation by clearing forest for agriculture again and again. It is an act of deforestation.
Q3. In which condition gene ratio remains constant in a species?
Answer : Option A
Explaination / Solution:
Gene ratio remains constant in species having random mating. Gene flow, mutation and sexual selection are the factors that change the gene ratio of the population.
Q4. Birth control measure should be
Answer : Option D
Explaination / Solution:
Good birth control measure should be easily available and cheaper. There should be not interference with sexual desire without any side effect.
Q5. Production of a human protein in bacteria by genetic engineering is possible because
Answer : Option C
Explaination / Solution:
Human protein can be produced in bacteria by genetic engineering because genetic code is universal i.e. same codon in different organism’s code for same amino acids.
Q6. Identify the false statement out of the following
Answer : Option C
Explaination / Solution:
Androgen hormone is produced from leydig cells. Sertoli cells provide nutrition to spermatozoa or sperm and menstrual cycle get stopped during pregnancy.
Q7. Which one represents regulative function of forests
Answer : Option B
Explaination / Solution:
The regulative function of forest is storage and release of gases. Plants in forests converts carbon dioxide gas into oxygen during photosynthesis.
Q8. Two geographical regions, separated by high mountain ranges are
Answer : Option C
Explaination / Solution:
The geographical region Palarctic and Oriental are separated by high mountain ranges. The geographical separation do not allow the gene flow as mating is not possible between member of species.
Q9. Name the female condom introduced by Hindustan Latex and female health company of England in India.
Answer : Option A
Explaination / Solution:
Femidom is a female condom introduced by Hindustan latex and female health company of England in India. It is quite effective and prevents unwanted pregnancy along with sexually transmitted disease.
Q10. What does X replesent in the followwing diagram:
Answer : Option C
Explaination / Solution:
Figure shown above represent translation process in which protein is produced. Ribosome provide site for protein synthesis and t-RNA brings the amino acids. The ‘x’ is the polypeptide chain produced.
