two molecules or moieties combine to form one single molecule, together with the loss of a small molecule. When this small molecule is water, it is known as a dehydration reaction; other possible small molecules lost are hydrogen chloride, methanol, or acetic acid.
Some algae have chloroplasts and chlorophyll and obtain their energy through photosynthesis while some algae like euglena are both heterotrophic (decompose dead organic matter) and autotrophic (use photosynthesis) and can also obtain energy likewise.
The light would be best described as AN UNCONDITIONED STIMULUS.
An unconditioned stimulus refers to any stimulus which naturally evokes a response from the affected person. The response that is evoked is termed unconditioned response. In the question given above, the light is the unconditioned stimulus while the blinking is the unconditioned response.<span />
I am not sure how to answer
The Trout are probably not used to the water and their surroundings.