Q.63 Identify two CORRECT characteristic features of (P) Autogamy and (Q) Allogamy from the
following statements
1. Plant species usually does not depend on external agents
2. Plant species usually depends on external agents
3. Plant species normally produces progeny that are healthier and better adapted in nature
4. Plant species normally produces weaker progeny in several generations
(A)P-1,3
Q-2,4
(B)P-2,4
Q-1,3
(C)P-1,4
Q-2,3
(D)P-2,3
Q-1,4
Autogamy (self-pollination) does not rely on external agents and leads to weaker progeny over generations due to inbreeding depression, while allogamy (cross-pollination) depends on external agents like pollinators and produces healthier, better-adapted progeny via hybrid vigor. The correct matching is option (C).
Correct Answer
(C) P-1,4 Q-2,3
Autogamy vs Allogamy Features
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Autogamy (P): Self-pollination within the same flower/plant; no external agents needed (statement 1); homozygous progeny suffer inbreeding depression, yielding weaker offspring long-term (statement 4).
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Allogamy (Q): Cross-pollination between plants; requires wind/insects/animals (statement 2); heterosis creates vigorous, adaptable hybrids (statement 3).
Option Analysis
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(A) P-1,3 Q-2,4: Wrong. Autogamy (P) doesn’t produce healthier progeny (3 is allogamy trait); allogamy doesn’t weaken progeny (4 is autogamy).
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(B) P-2,4 Q-1,3: Wrong. Autogamy independent of agents (not 2); allogamy needs agents (not 1).
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(C) P-1,4 Q-2,3: Correct. Matches self-reliance/weak progeny for autogamy; agent-dependence/healthy progeny for allogamy.
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(D) P-2,3 Q-1,4: Wrong. Autogamy lacks agent dependence (not 2) and healthier progeny (not 3).
Introduction to Autogamy Allogamy Features
Autogamy allogamy characteristic features plant reproduction is a GATE Life Sciences staple in Q.63, contrasting self-pollination (P: no agents, inbreeding weakness) vs cross-pollination (Q: pollinators, hybrid vigor). Option (C) perfectly aligns traits for exam success.
Core Differences Table
| Feature | Autogamy (Self) | Allogamy (Cross) |
|---|---|---|
| Agent Dependence | None (1) | Pollinators/wind (2) |
| Progeny Quality | Weaker generations (4) | Healthier/adapted (3) |
| Genetic Outcome | Homozygous, low diversity | Heterozygous vigor |
Q.63 Step-by-Step Matching
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P (Autogamy): 1 (independent), 4 (inbreeding depression).
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Q (Allogamy): 2 (external agents), 3 (better adaptation).
Answer: (C)—avoids distractors mixing traits.
Why These Traits Matter
Autogamy preserves genotypes in isolation (peas); allogamy evolves via recombination (maize). GATE tests: Inbreeding depression = weaker; outbreeding = hybrid vigor.
GATE Plant Reproduction Tips
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Mnemonic: “Auto Alone Weakens (1,4); Allo Agents Advance (2,3).”
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Examples: Autogamy (wheat selfers); Allogamy (sunflowers).
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High-yield: Link to geitonogamy (allogamy subtype).
Master autogamy allogamy characteristic features plant reproduction for top botany scores.
