Can the energy, in an ecosystem, flow forwards and backwards?

What are the two causes of density in deep current waters? a. salinity (how much salt) of the water and high temperaturesb. salinity (how much salt) of the water and low temperatures c. oxygen content of the water and high temperatures. d. oxygen content of the water and low temperatures

Which of the following types of reactions would decrease the entropy within a cell? a. dehydration reaction, b. hydrolysis, c. respiration, d. digestion, e. catabolism.

There are two tomato plantlets one of them is kept in an oxygen chamber with a light source and another is kept in sunlight. both of them are watered regularly what will be the observation after two weeks