AP BIOLOGY

Detailed explanation-1: -Population: A population is a group of organisms of the same species that live in the same area at the same time. Population ecologists study the size, density, and structure of populations and how they change over time.

Detailed explanation-2: -The many different species that live together in a habitat are called a community. An ecosystem, or ecological system, consists of a community and all the physical aspects of its habitat, such as the soil, water, and weather.

Detailed explanation-3: -Ecosystem: The collection of all living organisms in a geographic area, together with all the living and non-living things with which they interact.

Detailed explanation-4: -A species is a group of living organisms which are very closely related and can reproduce among themselves.