Biology Circulation / Transport NUMS 2024
PMDC Verified Question 8 of 54
The presence of which molecules distinguish blood from interstitial fluid?
A
Large proteins and electrolytes
B
Glucose and RBCs
C
Antibodies and electrolytes
D
RBCs and large proteins
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option D: RBCs and large proteins
Concept:

Capillary walls act as biological sieves, allowing small molecules to exit into the tissues while retaining massive structures.

Formula:

None

Solution:

  • Interstitial fluid is formed when hydrostatic pressure pushes blood plasma out of the capillaries.


  • Water, glucose, amino acids, and electrolytes easily pass through the endothelial clefts.


  • However, formed cellular elements like Red Blood Cells (RBCs) and massive molecules like large plasma proteins (albumin, fibrinogen) are physically too large to escape. Thus, their presence strictly distinguishes whole blood from the fluid bathing the tissues.


Why other options are incorrect:

  • Electrolytes, glucose, and even some smaller antibodies easily cross into the interstitial fluid.

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.

Previous Question All Circulation / Transport MCQs Next Question

Want to solve full-length papers under timed exam conditions?

Practice with zero-scroll lockdown sprints, dynamic latency zone timers, live peer selection telemetry, and the automated Amber mistake recovery loop.

Enter Arena Sprint iOS App Android App