Which kingdom includes multicellular organisms with cell walls made of chitin and obtain energy by decomposing or digesting organic material?

Which kingdom includes multicellular organisms with cell walls made of chitin and obtain energy by decomposing or digesting organic material?

• A. Protista
• B. Animalia
• C. Fungi
• D. Plantae

Answer: (C)

The key idea is organisms that have cell walls made of chitin and obtain energy by breaking down external organic material and then absorbing nutrients. This describes fungi, which are typically multicellular and grow as networks of hyphae. They secrete enzymes to digest complex organic matter outside their bodies and then absorb the resulting nutrients. That absorptive, decomposing mode of nutrition is distinct from plants, which use photosynthesis and have cellulose cell walls, and from animals, which generally lack cell walls altogether and digest food internally. Protists are diverse, but chitin-containing cell walls are a hallmark most associated with fungi. Therefore, the kingdom is fungi.

The key idea is organisms that have cell walls made of chitin and obtain energy by breaking down external organic material and then absorbing nutrients. This describes fungi, which are typically multicellular and grow as networks of hyphae. They secrete enzymes to digest complex organic matter outside their bodies and then absorb the resulting nutrients. That absorptive, decomposing mode of nutrition is distinct from plants, which use photosynthesis and have cellulose cell walls, and from animals, which generally lack cell walls altogether and digest food internally. Protists are diverse, but chitin-containing cell walls are a hallmark most associated with fungi. Therefore, the kingdom is fungi.