WAEC Biology 2010 Theory — Question 9

Model answer

(i) Population density is defined as the number of individuals of a species per unit area of the habitat: Population density = Population size / Area of habitat. (ii) Abiotic components (such as temperature, light, water, and soil) influence which organisms (biotic components) can survive in an environment, while the biotic components in turn affect the abiotic conditions - for example through respiration, decomposition and modification of soil and microclimate. Together, they interact continuously to shape the structure and function of the ecosystem.