Question

The organisms shown in figure can be grouped into two separate groups based on their mode of nutrition.
Which of the following options is correct regarding this?

• A. P is an autotroph whereas Q, R and S are heterotrophs.
• B. P show intracellular digestion while Q, R and S show extracellular digestion.
• C. P and Q are autotrophs while R and S are heterotrophs.
• D. P shows intracellular digestion while Q, R and S show extracellular digestion.

Answer 1

Answer: (A)

P is an autotroph whereas Q, R and S are heterotrophs.

Autotrophic green algae e.g., Chlamydomonas (P) are a group of microorganisms that are able to make their own food. It takes inorganic substances and turns them into organic substances that can be broken down. There are two major classes of autotrophs: chemoautotrophs and photoautotrophs. Heterotrophs are organisms that get the carbon necessary for life from organic substrates. They cannot synthesize organic compounds from inorganic sources in the environment like an autotroph can. Heterotrophs are known as consumers in the food chain. Protista like amoeba (R), fungi like a mushroom (Q) and mould (S) are all heterotrophs.