Which biological agents are non-living substances, produced by living plants, animals, or bacteria, and are some of the most lethal substances known.

the answer is:

carbon dioxide

some fungi obtain their nutrients from a living host (plant or animal) and are called most biotrophic fungi have fairly narrow host ranges—they are specialized on a limited called rhizomorphs that allow the fungus to grow from one tree to another. ascospores are formed inside a sac-like structure called an ascus. so your answer is a

the tricuspid valve is present between right atrium and right ventricle