Answer:
Intraspecific interactions, where they are the same species, or interspecific interactions, where they are from different species.
During exercise there is an increase in physical activity and muscle cells respire more than they do when the body is at rest. The heart rate increases during exercise. The rate and depth of breathing increases - this makes sure that more oxygen is absorbed into the blood, and more carbon dioxide is removed from it.
Population refers to an array of organisms of the similar species, which thrives in a particular geographical region and interbreed. The three main characteristics of a population are density, size, and dispersion.
The density signifies towards how many organisms are thriving in a specific region. The size refers to how big a population is, and dispersion signifies towards the degree of spreading of the particular population.