Which of these species would you classify as a profundal zone organism?
question 14 options:

frog

plankton

crayfish

floating water plants

Plankton species are commonly classified as a profundal zone organism.

Explanation:

In inland standing water reserve such as lake or ponds, sunlight penetrate through the water into a certain depth. Below that level, the light does not reaches. Also the area is below the thermocline zone of water, that is, the vertical zone along which the temperature decreases sharply. This area or layer is known as profundal zone and the organisms found in this zone are called profundal zone organisms, The marine organisms belonging to plankton species generally thrive in profundal zone.

answer: b: experiments that showed that all cells are similar in how they metabolize and in their composition

explanation:

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.