Multiple Choice Questions (MCQs)
1. The gynoecium represents:
A. Male reproductive part
B. Female reproductive part
C. Sterile part
D. Accessory organ
Answer: B
2. A flower with fused carpels is called:
A. Apocarpous
B. Syncarpous
C. Monocarpellary
D. Bisexual
Answer: B
3. The part of pistil that receives pollen grains is:
A. Style
B. Ovary
C. Stigma
D. Placenta
Answer: C
4. The ovules are attached to:
A. Style
B. Stigma
C. Placenta
D. Micropyle
Answer: C
5. The opening in the ovule through which pollen tube enters is:
A. Hilum
B. Chalaza
C. Micropyle
D. Nucellus
Answer: C
6. Megasporogenesis involves:
A. Mitosis
B. Meiosis
C. Fertilization
D. Pollination
Answer: B
7. Number of megaspores formed after meiosis of MMC:
A. 2
B. 3
C. 4
D. 8
Answer: C
8. Typical angiosperm embryo sac is:
A. 8-celled, 7-nucleate
B. 7-celled, 8-nucleate
C. 6-celled, 8-nucleate
D. 8-celled, 8-nucleate
Answer: B
9. The synergids are located at:
A. Chalazal end
B. Micropylar end
C. Center
D. Nucellus
Answer: B
10. Cells present at chalazal end are:
A. Synergids
B. Egg cell
C. Antipodals
D. Polar nuclei
Answer: C
11. During monosporic development, the embryo sac develops from:
A. All four megaspores
B. Two megaspores
C. One functional megaspore
D. Megaspore mother cell directly
Answer: C
12. Free nuclear divisions in embryo sac formation imply:
A. Cytokinesis occurs before mitosis
B. Nuclear division without cell wall formation
C. Only one nucleus divides
D. Meiosis without cytokinesis
Answer: B
13. Which structure is directly responsible for guiding pollen tube?
A. Egg cell
B. Antipodals
C. Synergids
D. Polar nuclei
Answer: C
14. If the MMC fails to undergo meiosis, the resulting embryo sac would be:
A. Haploid
B. Diploid
C. Triploid
D. Sterile only
Answer: B
15. Which of the following correctly represents the sequence?
A. MMC → Megaspore → Embryo sac → Ovule
B. Ovule → MMC → Megaspore → Embryo sac
C. MMC → Ovule → Embryo sac → Megaspore
D. Megaspore → MMC → Ovule → Embryo sac
Answer: B
16. The central cell becomes triploid after:
A. Syngamy
B. Double fertilization
C. Triple fusion
D. Pollination
Answer: C
17. Which of the following is NOT haploid?
A. Egg cell
B. Synergids
C. Antipodals
D. Nucellus
Answer: D
Reasoning Questions (Answer briefly)
1. Why is meiosis important in megaspore mother cell (MMC)?
Answer: It reduces chromosome number to haploid and produces genetic variation.
2. Why is only one megaspore functional?
Answer: The other three degenerate to provide nourishment to the functional megaspore.
3. Why are synergids important?
Answer: They guide the pollen tube into the embryo sac using the filiform apparatus.
4. Why is the embryo sac called female gametophyte?
Answer: Because it produces female gametes (egg cell) and is haploid.
5. Why is nucellus rich in food materials?
Answer: It nourishes the developing embryo sac.
Assertion–Reason Questions
1.
Assertion (A): The embryo sac is 8-nucleate and 7-celled.
Reason (R): Two nuclei remain free in the central cell.
Answer: Both A and R are true, and R is the correct explanation
2.
Assertion (A): Meiosis occurs in MMC.
Reason (R): It helps maintain chromosome number across generations.
Answer: Both A and R are true, and R is correct
3.
Assertion (A): Synergids help in fertilization.
Reason (R): They possess filiform apparatus.
Answer: Both A and R are true, and R is correct
4.
Assertion (A): All four megaspores develop into embryo sacs.
Reason (R): Megasporogenesis produces four megaspores.
Answer: A is false, R is true
5.
Assertion (A): The ovule is attached to placenta.
Reason (R): Placenta is present inside ovary.
Answer: Both A and R are true, but R is not the correct explanation
6.
Assertion (A): Embryo sac is called female gametophyte.
Reason (R): It produces egg cell and is haploid.
Answer: Both A and R are true, and R is correct
7.
Assertion (A): All megaspores are functional in angiosperms.
Reason (R): Meiosis produces four megaspores.
Answer: A is false, R is true
8.
Assertion (A): Synergids degenerate after fertilization.
Reason (R): They help in pollen tube entry.
Answer: Both A and R are true, but R is not the correct explanation
9.
Assertion (A): Embryo sac is 8-nucleate but 7-celled.
Reason (R): Two polar nuclei are present in one central cell.
Answer: Both A and R are true, and R is correct
10.
Assertion (A): Nucellus is haploid.
Reason (R): It surrounds the embryo sac.
Answer: A is false, R is true
Exam Tip (Very Important)
Remember these high-yield points:
7-celled, 8-nucleate embryo sac
Monosporic development
MMC → meiosis → 4 megaspores → 1 functional
Synergids + filiform apparatus = pollen tube guidance
Triple fusion → triploid endosperm
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