Questions: Microbes that are pathogenic to humans and animals are in their requirement for pre-formed organic matter. heterotrophic autotrophic phototrophic

The answer is the first one: heterotrophic.

Explanation for each option:

1. Heterotrophic: This is correct. Pathogenic microbes, which cause diseases in humans and animals, require pre-formed organic matter for their growth and energy. They obtain their nutrients by consuming organic compounds, which makes them heterotrophic.

2. Autotrophic: This is incorrect. Autotrophic organisms can produce their own food from inorganic substances like carbon dioxide and water, using light (photosynthesis) or chemical energy (chemosynthesis). Pathogenic microbes do not typically have this capability.

3. Phototrophic: This is incorrect. Phototrophic organisms obtain their energy from light. While some microbes are phototrophic, pathogenic microbes that infect humans and animals are not typically phototrophic.

Summary: Pathogenic microbes that infect humans and animals are heterotrophic because they require pre-formed organic matter for their nutrition and energy.