Examkin

Question

Difficulty: MediumKingdom Fungi: Moulds, Yeasts, and Mushrooms

During a field study on forest soil decomposition, a student observes a mushroom (*Agaricus*) releasing digestive enzymes onto decaying plant litter before absorbing the dissolved organic nutrients. Which mode of nutrition and cell wall composition are characteristic of this organism?

  1. Saprophytic nutrition and a chitin cell wallAnswer
  2. B
    Holozoic nutrition and a cellulose cell wall
  3. C
    Autotrophic nutrition and a peptidoglycan cell wall
  4. D
    Holozoic nutrition and a chitin cell wall

Answer

Saprophytic nutrition and a chitin cell wall
Fungi are heterotrophic organisms that feed saprophytically by secreting digestive enzymes directly onto dead or decaying organic substrate and subsequently absorbing the simple dissolved nutrients through their chitinous cell walls.

Step-by-Step Solution

1
Determine the mode of nutrition from the biological description
Secreting enzymes outside the body onto dead substrate and absorbing dissolved products constitutes extracellular saprophytic nutrition
Fungi are non-photosynthetic heterotrophs that cannot ingest solid food holozoically due to rigid cell walls
2
Identify the structural polysaccharide of fungal cell walls
The cell walls of fungi are composed of chitin
Chitin provides structural strength to fungal hyphae, distinguishing Kingdom Fungi from plants (cellulose) and bacteria (peptidoglycan)

Key Concept

Fungal Saprophytism and Chitinous Cell Wall
Rate this question

Topics

Kingdom Fungi: Moulds, Yeasts, and Mushrooms

More questions from this topic