Natural selection leads to increases in the mean fitness of populations and so will reduce the frequency of disease-associated alleles, but other evolutionary processes, such as mutation and gene flow, may introduce or increase the frequency of these deleterious alleles.
The difference is that "Net production is always less than gross production".
Option (b);
<u>EXPLANATION: </u>
Net production is the rate at which all plants, algae, bacteria produce net chemical energy in the useful ecosystem. The formula statement is that Net Production = Gross Production - Respiration by plants.
Whereas, Gross production is the total sum of energy that is produced by the producer. It is the energy in that area in a given amount of time. Gross production doesn't include the energy that is lost in respiration. Thus the production value is less than gross production.
Prey-predator relationship. Explanation: The relationship between the praying mantis feeding on a bee.
