What is the importance of positive and negative controls in an experiment with a mouse and different foods with the hypothesis that if i feed the mouse more food it will gain weight

Negative control in an experiment is that set of organism that do not receive the treatment.

Explanation:

However, positive control in an experiment is that set of organism that receives the treatment. Both the sets of control groups are used for comparison purpose.

In the experiment with mice to validate the hypothesis which states that more food increases the weight of the mice, the set of mice as negative control is fed just with water and the one as the positive control is fed with food. The positive control is expected to show positive result.

answer: - few nutrients

high pressure

low temperatures

explanation: 1. few nutrients:   open-ocean zone is located way far from the land, which is the main source of the essential nutrients.2. high pressure: pressure increases by 1 atmosphere for every 10 meters increase in depth.3. ample sunlight: a large fraction of the sunlight is reflected back to the atmosphere from the sea surface. 4. varying salinity: below the thermocline, the water is isolated from the atmosphere so the salinity remains stable over the year.5. low temperatures:   the temperature of open-ocean zone ranges from a low of -2°c to an average of 17°c