IB Biology Sub-topic B4.1 Notes

Next up, you need to learn about habitats and how organisms make a living in an ecosystem. A habitat is officially defined as the place where a community, species, or organism lives. This can typically be described by the geographical and physical location and the type of ecosystem.

Each habitat is thus defined by its abiotic factors. To understand this, remember that ecosystems are composed of two types of factors:

1. Biotic factors - these are living things, such as animals, plants, or bacteria.
2. Abiotic factors - these are non-living things, such as water, air, and the sun.

Biotic factors can be further sub-divided into three categories:

1. Species - a group of organisms that can produce fertile offspring.
2. Population - a group of organisms of the same species living in the same area at the same time.
3. Community - multiple populations living in the same area at the same time.