Difficulty: Easy
Correct Answer: Plant cells are less sensitive to shear than microbial cells
Explanation:
Introduction / Context:
Plant cell and tissue cultures are key to micropropagation, metabolite production, and genetic engineering. Their physical and physiological characteristics differ markedly from microbial cultures, impacting reactor design, agitation, and process yields.
Given Data / Assumptions:
Concept / Approach:
Due to large size, fragile cell walls, and vacuolation, plant cells are typically more shear sensitive than bacteria or fungi. They require gentler mixing (low tip speeds) and specialized impellers. Clumping is common, affecting oxygen/nutrient gradients and complicating homogeneous growth. Hormone balance (auxins/cytokinins) controls morphogenesis. Therefore, any statement claiming plant cells are “less shear sensitive” than microbes is incorrect.
Step-by-Step Solution:
List known traits: large size, aggregation, hormone dependence.Contrast shear tolerance: microbes > plant cells for typical agitation regimes.Identify the incorrect option as the one stating “less sensitive to shear.”
Verification / Alternative check:
Bioreactor guidelines recommend gentle agitation, bubble-free aeration (membrane sparging), and shear protectants (e.g., Pluronic F-68) for plant cells, confirming higher shear sensitivity.
Why Other Options Are Wrong:
Common Pitfalls:
Applying microbial agitation/aeration parameters to plant cultures; ignoring aggregate size control.
Final Answer:
Plant cells are less sensitive to shear than microbial cells.
Discussion & Comments