Question

VAM is
A. Symbiotic bacteria
B. Saprophytic bacteria
C. Saprophytic fungi
D. Symbiotic fungi

Answer 1

Here the VAM stands for Vesicular-arbuscular Mycorrhiza. If we break down the word into four pieces as vesicular (related to vesicle), arbuscular (little tree – Latin word), myco (the Latin word for fungi), and rhiza (Latin word for root). Prokaryotes or unicellular organisms are widely dependent on others to get nutrients.

Complete answer:
Let’s understand the definition of Saprophyte and Symbiote. Microorganisms such as fungi or bacteria, which grow on decaying organic matter and absorb nutrition from it are known as saprophytes. While symbiote is the organism that has a partnership with other living organisms to profit each other. As stated in a hint, VAM includes the relation between root and fungi. Mycorrhizal association shows symbiotic relations between fungi and root. Both fungi and roots help each other to proliferate. Fungi helps plants to absorb nutrients such as phosphorus, sulfur, nitrogen and water from soil and in return plants provide food which is produced by photosynthesis.

So, the correct answer is D which is symbiotic fungi.

Additional information:
Arbuscular mycorrhizas have unique structures, arbuscules, and vesicles produced by fungi of the phylum Glomeromycota. These mycorrhizas work such as fungi that help roots to absorb nutrients such from the soil. VAM is found in 80% of vascular plant families that exist today. There are two hypotheses that state how VAM has become a symbiote. From which one states that it has evolved from a parasite interaction that developed into this beneficial relationship. Another hypothesis states that it could have developed from saprobic fungi that became endosymbiotic.

Note: There are two kinds of mycorrhiza can be seen such as ectomycorrhizae and endomycorrhizae. Vesicular-arbuscular Mycorrhiza (VAM) is being used as a biofertilizer for horticulture plants in developing countries. The VAM acts as a tool to the root hairs while absorbing nutrients from the soil. It also helps root to absorb water to overcome drought.