Slime molds versus true molds: In what main way do slime molds differ from filamentous (moldy) fungi?

Introduction / Context:
Slime molds (mycetozoans) are fungus-like protists that resemble fungi superficially but differ markedly in nutrition and life cycles. Distinguishing them from true molds is a common exam theme.

Given Data / Assumptions:

• Slime molds exhibit amoeboid cells or plasmodia lacking rigid fungal cell walls.
• True molds (fungi) have chitinous walls and absorb nutrients after extracellular digestion.
• Nutrition mechanism is the key distinction.

Concept / Approach:
Slime molds ingest particulate food by phagocytosis, similar to amoebae. Moldy fungi secrete enzymes and absorb soluble products (absorptive heterotrophy). Furthermore, slime molds produce amoeboid or flagellated cells, not molds; the inverse statement is incorrect.

Step-by-Step Solution:
Focus on nutrition: phagocytosis (slime molds) vs. absorption (fungi). Check statements about cell types: slime molds do produce amoeboid/flagellated stages; molds do not. Accept option (a) and reject option (b), therefore not “both.” Select the single correct distinction: option (a).

Verification / Alternative check:
Cell wall chemistry: fungi have chitin; many slime mold stages lack chitinous walls, supporting their protistan nature.

Why Other Options Are Wrong:

• (b): Reversed; slime molds (not molds) have amoeboid/flagellated cells.
• (c): Includes incorrect (b).
• (d): There is a correct statement (a).
• (e): Slime molds do not share identical chitinous walls with true fungi across their life cycle.

Common Pitfalls:
Equating superficial “moldy” appearance with fungal biology and ignoring nutrition mode.

Final Answer:
in their mode of nutrition: phagocytosis for the slime molds; absorptive heterotrophy for moldy fungi.