Storage products — Starch as the primary energy reserve is characteristic of which algal division?
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Achlorophyta
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Bchrysophyta
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Cphaeophyta
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Drhodophyta
Answer
Correct Answer: chlorophyta
Explanation
Introduction / Context:Energy storage compounds are central to algal systematics. Different divisions store photosynthate in distinct forms, and this biochemical fingerprint helps separate major groups.
Given Data / Assumptions:
- Chlorophyta (green algae) store as starch within chloroplasts, similar to land plants.
- Chrysophyta sensu lato (including diatoms, golden algae) store as chrysolaminarin or oils.
- Phaeophyta (brown algae) store laminarin and mannitol.
- Rhodophyta (red algae) store floridean starch (distinct from plant starch).
Concept / Approach:Among the options, classic “starch” as in green lineages is associated with Chlorophyta. Though Rhodophyta have floridean starch, the conventional match for “starch” in basic MCQs is Chlorophyta.
Step-by-Step Solution:
Map each division to its storage product.Identify “starch” with Chlorophyta in standard teaching.Choose Chlorophyta.Verification / Alternative check:Biochemistry texts and phycology keys list starch for green algae and laminarin/mannitol for brown algae.
Why Other Options Are Wrong:
- Chrysophyta: chrysolaminarin/oils.
- Phaeophyta: laminarin/mannitol.
- Rhodophyta: floridean starch (chemically distinct from plant starch).
Common Pitfalls:Confusing floridean starch with plant-like starch; exam convention points to Chlorophyta.
Final Answer:chlorophyta