Question
Choose the correct option for the Assertion (A) and Reason (R) given below:
Assertion (A): In many pteridophytes, the transition from protostele to more complex stelar systems such as siphonostele is associated with increasing structural complexity and leaf evolution.
Reason (R): The development of leaf gaps in the vascular cylinder is linked to the origin of megaphyllous leaves and contributes to the formation of siphonostelic conditions.
Asked in UP PGT (Biology) · 2026
Tissues and Tissue System · Biology
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Transpiration is the loss of water vapour, mainly through leaf stomata.
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Questions Asked from Algae: Types, Structure & Economic Importance in Previous Exams
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Algae: Types, Structure & Economic Importance has appeared in 42 previous-year exam questions, most frequently in State PSC, UPSC and SSC.
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