Reproduction in Organisms (PYQs)

Correct Answer: (b)
An offset is a vegetative structure formed by mitotic cell divisions. Since vegetative propagation is a form of asexual reproduction, the progeny are genetically identical clones of the parent plant.

Correct Answer: (c)
The quantity and spatial distribution of yolk within an egg dictate the pattern and rate of cleavage (e.g., holoblastic vs. meroblastic).

Correct Answer: (c)
Groundnut (Arachis hypogaea) produces geocarpic fruits; after fertilization, the peg elongates downward pushing the ovary below ground to mature into a pod.

Correct Answer: (c)
Mint reproduces vegetatively via sub-aerial stem modifications called suckers.

Correct Answer: (c)
In the monoecious alga Chara, the female sex organ (oogonium/nucule) is situated at the top, and the male sex organ (antheridium/globule) is located below it on the same node.

Correct Answer: (c)
Most algae undergo external fertilization (syngamy outside the parental body) in an aqueous medium.

Correct Answer: (a)
Onion reproduces vegetatively via an underground bulb stem modification. Ginger propagates through rhizomes, Chlamydomonas produces motile zoospores, and Yeast reproduces through budding/ascospores.

Correct Answer: (b)
In Oomycetes (and oogamous reproduction in general), the female gamete is large and non-motile, while the male gamete is smaller and motile.

Correct Answer: (b)
Water hyacinth (Eichhornia crassipes) propagates vegetatively through offsets, not runners.

Correct Answer: (b)
Epimorphosis is the type of regeneration involving active cell proliferation (blastema formation) to replace a lost organ or body part.

Correct Answer: (c)
Fertilization involves fusion of two haploid gametic genomes ( + n$), doubling the cellular DNA content back to the diploid state ($2n$).

Correct Answer: (d)
Vegetative propagation in ginger occurs through an underground modified stem called a rhizome.

Correct Answer: (b)
Cleavage involves rapid, repeated mitotic divisions of the zygote without growth phases between divisions; hence, the total embryo size remains constant while individual cell (blastomere) size decreases.

Correct Answer: (d)
Perennial plants live for several years and continue to flower/fruit seasonally without dying, whereas biennials complete their entire lifecycle and die after flowering in their second year.

Correct Answer: (b)
Leaves of both Bryophyllum and Kalanchoe possess adventitious buds along their leaf margins capable of vegetative propagation.

Correct Answer: (d)
Apomixis is a form of asexual reproduction in plants that mimics sexual reproduction by producing seeds without fertilization/syngamy.

Correct Answer: (d)
Meiocytes are specialized diploid precursor cells ($2n$) that undergo meiotic division to produce haploid gametes or spores.

Correct Answer: (a)
Bamboo is a monocarpic plant that flowers only once in its lifetime (usually after 50–100 years), sets seed, and then dies.

Correct Answer: (b)
A clone is a group or population of genetically identical individuals derived through asexual reproduction.

Correct Answer: (c)
Agave reproduces vegetatively by means of bulbils, which are modified floral buds that drop to the ground and grow into new plants.

Correct Answer: (d)
Vegetative propagation and apomixis are both asexual modes of reproduction that bypass meiotic syngamy, producing progeny genetically identical to the parent (clones).

Correct Answer: (b)
Binary fission is characteristic of unicellular organisms like Amoeba and Paramecium. Sargassum is a multicellular brown alga that reproduces vegetatively through fragmentation, not binary fission.

Correct Answer: (d)
The 'eyes' of a potato tuber are axillary buds located at the nodes of the modified underground stem.

Correct Answer: (d)
Development of an unfertilized female gamete directly into an embryo/organism is called parthenogenesis.

Correct Answer: (a)
Differentiation is the developmental process where unspecialized embryonic cells acquire distinct structural and functional identities.