Biology Homeostasis PMDC Conceptual Practice
PMDC Verified Question 91 of 99
Excretion and osmoregulation in flatworms such as Planaria are mediated by a tubular network of:
A
Malpighian tubules
B
Protonephridia equipped with flame cells
C
Metanephridia
D
Glomerular nephrons
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option B: Protonephridia equipped with flame cells
Concept: Protonephridial excretory system.

Solution: Flatworms (Planaria) possess protonephridia—a network of dead-end tubules driven by ciliated flame cells that propel fluid out through excretory pores.

Why other options are incorrect:
  • Option A: Malpighian tubules are found in insects.

  • Option C: Metanephridia open into coelomic cavities in annelids.

  • Option D: Nephrons are functional units of vertebrate kidneys.

Quality & Fidelity Assurance: Every question on BeambePrep is rigorously curated against the official PMDC syllabus with zero filler, zero out-of-syllabus content, and zero typos. When an authentic past paper originally contained a historical mistake or ambiguity from the examining board (such as UHS or NUMS), BeambePrep faithfully reflects the original paper while detailing the nuance and scientific consensus in the autopsy above.

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