Question

as bod (biological oxygen demand) increases, aquatic organisms have a harder time breathing. what does an increase in bod do to the amount of dissolved oxygen in water?
greatly increases it
slightly increases it
significantly decreases it
does not change it

Explanation:

BOD (biological oxygen demand) measures the amount of oxygen that bacteria and other microorganisms consume while decomposing organic matter in water. When BOD increases, it means there is more organic matter for these organisms to break down. As they decompose this organic matter, they use up dissolved oxygen in the water. So, an increase in BOD leads to a decrease in dissolved oxygen levels.

Answer:

significantly decreases it