Chapter 2, Problem 22A

Summary Introduction

Introduction: 

A detritivore is an organism that feeds on dead and decaying matter present in the ecosystem. These organisms play an important role in returning nutrients to their original sources like soil, water, and air. Detritivore organisms include many insects that live at bottoms of aquatic environments and worms. 

Answer to Problem 22A

Correct answer:

The correct answer is option (D) crayfish.

Explanation of Solution

Explanation/justification for the correct answer:

Option (D) crayfish. Crayfishes are the freshwater organisms that resemble the lobster-like body structure. These organisms belong to the phylum Arthropoda and class Crustacea. Crayfishes feed on decaying vegetation or animal matter. So, the correct answer is option (D).

Explanation for incorrect answer: 

Option (A) cat. Cats are the mammals that are unable to produce their own food and thus depend on others for their energy and nutrient requirements. Cats are omnivores that can feed on live animals or plants. So, this is an incorrect option.

Option (B) mouse. A mouse is also a mammal that is unable to produce their own food and thus depends on others for their energy and nutrient requirements. Mouse are omnivores that can feed on live animals or plants. So, this is an incorrect answer.

Option (C) sunflower. Sunflower is a plant that is capable of preparing their own food. Plants perform photosynthesis to convert inorganic molecules into organic ones using energy from the sun. Thus they are autotrophs. So, this is an incorrect answer.