SECTION A
Questions Marks
1. Why does endosperm development precede embryo development?
2. How many meiotic divisions are required to produce 76 seeds in a Guava fruit?
3. How does pollination take place in water hyacinth and water lily?
4. Name the glands that contribute to human seminal plasma.
5. A snapdragon plant with violet flowers was crossed with another such plant with white flowers. The F1 progeny obtained had pink flowers. Explain, in brief, the inheritance pattern seen in offsprings of F1 generation?
6. Differentiate between aneuploidy and polyploidy.
7. Predict the effect if, the codon UAU coding for an amino acid at the 25th position
of a polypeptide of 50 amino acids, is mutated to UAA.
8. Differentiate between pro-insulin and mature insulin.
9. Name the commonly used vector for cloning genes into higher organisms.
10. Which of the three forests- Temperate, Mangroves and Tropical Evergreen is more vulnerable to invasion by outside animals and plants?
11. Assertion: Primary transcripts in eukaryotes are nonfunctional.
Reason: Methyl guanosine triphosphate is attached to 5’ – end of hnRNA.
a. Both assertion and reason are true, and reason is the correct explanation of assertion.
b. Both assertion and reason are true, but reason is not the correct explanation of assertion.
c. Assertion is true but reason is false.
d. Both assertion and reason are false.
OR
Assertion: An organism with lethal mutation may not even develop beyond the zygote stage.
Reason: All types of gene mutations are lethal.
a. Both assertion and reason are true, and the reason is the correct explanation of the assertion.
b. Both assertion and reason are true, but the reason is not the correct explanation of the assertion.
c. Assertion is true but reason is false.
d. Both assertion and reason are false
12. Assertion: E. coli having pBR322 with DNA insert at BamHI site cannot grow in medium containing tetracycline.
Reason: Recognition site for Bam HI is present in tetR region of pBR322.
a. Both assertion and reason are true, and the reason is the correct explanation of the assertion.
b. Both assertion and reason are true, but the reason is not the correct explanation of the assertion.
c. Assertion is true but reason is false.
d. Both assertion and reason are false
13. Assertion: A community with more species is more stable than that with less species.
Reason: More the number of species, lesser the variation in the total biomass production year after year.
a. Both assertion and reason are true, and the reason is the correct explanation of the assertion.
b. Both assertion and reason are true, but the reason is not the correct explanation of the assertion.
c. Assertion is true but reason is false.
d. Both assertion and reason are false
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