The sheath enclosing the radicle and root cap in a monocot embryo is called:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Coleorrhiza
Explanation: At its lower end, the embryonal axis has the radical and root cap enclosed in an undifferentiated sheath called coleorrhiza.
Non-albuminous seeds are found in:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: C
Answer: Pea
Explanation: Non-albuminous seeds have no residual endosperm (e.g., pea, groundnut).
The micropyle in a seed facilitates the entry of:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Oxygen and water
Explanation: The micropyle remains as a small pore in the seed coat. This facilitates entry of oxygen and water into the seed during germination.
The wall of the fruit developed from the ovary wall is called:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: C
Answer: Pericarp
Explanation: The wall of the ovary develops into the wall of fruit called pericarp.
Which of the following is a true fruit?
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: D
Answer: Mango
Explanation: Apple, strawberry, and cashew are false fruits where the thalamus contributes. Most fruits (like Mango) develop only from the ovary and are true fruits.
The 2000-year-old viable seed discovered at King Herod's palace was:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Phoenix dactylifera
Explanation: A recent record of 2000 years old viable seed is of the date palm, Phoenix dactylifera discovered during the archeological excavation at King Herod's palace.
Orchid fruits are characterized by containing:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: C
Answer: Thousands of tiny seeds
Explanation: Orchid fruits are one such category and each fruit contain thousands of tiny seeds.
In apomixis, the diploid egg cell is formed without:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Reduction division (Meiosis)
Explanation: In some species, the diploid egg cell is formed without reduction division and develops into the embryo without fertilization.
Nucellar polyembryony is a characteristic feature of:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: A
Answer: Citrus
Explanation: More often, as in many Citrus and Mango varieties some of the nucellar cells... develop into the embryos.
What is the main advantage of apomictic seeds to farmers?
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: They maintain hybrid characters indefinitely
Explanation: If these hybrids are made into apomicts, there is no segregation of characters in the hybrid progeny. Then the farmers can keep on using the hybrid seeds.