The brain and the spinal cord.
A. A statement of purpose
So abiotic means nonliving, so the only abiotic option is B. the gravel on the bottom of the aquarium.
In the scenario give above, the disease reservoir is the PARROT and the possible transmission method is INDIRECT CONTACT THROUGH AIR.
Disease reservoir refers to a source of a particular pathogen in an environment. A disease reservoir can be a person, an animal or an inanimate object like soil. In the case given above, the parrot is the disease reservoir and it passes the disease pathogen to the student. Pathogens are transmitted through four distinct ways, these are: direct contact, indirectly through the air, indirectly through contaminated object and through vectors. The disease pathogen was possibly passed to the student when the parrot was talking via tiny mucus droplets that escape from the bird's mouth.
A solute is a substance that is dissolved in the solvent.
Some examples of a solute are sugar in water, carbon dioxide in water, and sodium chloride in water.
