Question

Lichens exhibit a symbiotic relationship between...............

• A. Bacteria and fungus
• B. Virus and fungus
• C. Alga and fungus
• D. Amoeba and fungus

Hint:

A useful mnemonic to remember the roles in a lichen is: "Alice Alga and Freddie Fungus took a LICHEN to each other." Alice (the alga) is a good cook (photosynthesis), and Freddie (the fungus) provides a strong house (structure and protection).

Answer 1

The Correct Option is C

Step 1: Understanding the Concept
The question asks to identify the two types of organisms that form the composite organism known as a lichen through a symbiotic relationship. A symbiotic relationship is a close and long-term interaction between two different biological species.

Step 2: Defining Lichen Symbiosis


Lichens are a classic example of mutualism, a type of symbiosis where both partners benefit.

A lichen consists of a fungal partner (the mycobiont) and one or more photosynthetic partners (the photobiont).
\t- The fungus provides the structure, protection, water, and minerals.
\t- The photosynthetic partner, which is usually a green alga or a cyanobacterium (formerly called blue-green alga), produces food (carbohydrates) through photosynthesis.


Step 3: Evaluating the Options


(A) Bacteria and fungus: This is partially correct as cyanobacteria can be a partner, but "Alga" is the more common and specific partner type listed.

(B) Virus and fungus: This is incorrect.

(C) Alga and fungus: This is the correct and classic definition of the symbiotic relationship in lichens.

(D) Amoeba and fungus: This is incorrect.


Step 4: Final Answer
Lichens are a symbiotic partnership between a fungus and an alga (or cyanobacterium). Therefore, option (C) is the correct answer.