Preliminary Biology Yearly Notes
Biology Year 11 Yearly Notes
Chapter One – A local ecosystem
1.1 Terrestrial and Aquatic Environments
-Ecosystem: any environment containing living organisms interacting with each other and with the non-living parts of that environment.
-Environment: the environment of an organism is its surroundings, both living and non-living
-Habitat: the habitat of an organism is the place where it lives.
Australian Environments
* Terrestrial environments are environments on land. Land covers about 35% of the Earth’s surface. * Aquatic environments are water environments. Oceans cover about 65% of the Earth’s surface. * Terrestrial and aquatic environments have very different abiotic characteristics.
Abiotic Characteristics
Characteristic | In Aquatic environments | In Terrestrial environments | Viscosity – viscosity is a measure of how hard it is to move through a gas or a liquid (fluid) | High viscosity – organisms have to be streamlined | Low viscosity; little resistance to movement | Buoyancy – buoyancy is the amount of support experienced by an object immersed in a liquid or gas. | High buoyancy; organisms do not have to support their bodies as much | Low buoyancy; organisms have to support their bodies with bones and the secondary thickening in plants | Temperature Variation | Less variation in temperature; colder with depth; small bodies of water heat up and cool down faster than larger bodies | Great variation – depends on altitude, location and time of day/year. | Pressure Variation | Increases rapidly with depth | Decreases with altitude | Avaliability of gases. | Quite low – depends on the temperature. Diffusion is slower. | Freely avaliable. Diffusion is rapid. | Avaliability of water. | Rarely a problem in aquatic environments | Varied – depends on location, rainfall, climate, etc. | Avaliaibility of ions | Salwater environments contain 3.5% of dissolved salts. Freshwater environments have low ion concentration. | Ions
Chapter One – A local ecosystem
1.1 Terrestrial and Aquatic Environments
-Ecosystem: any environment containing living organisms interacting with each other and with the non-living parts of that environment.
-Environment: the environment of an organism is its surroundings, both living and non-living
-Habitat: the habitat of an organism is the place where it lives.
Australian Environments
* Terrestrial environments are environments on land. Land covers about 35% of the Earth’s surface. * Aquatic environments are water environments. Oceans cover about 65% of the Earth’s surface. * Terrestrial and aquatic environments have very different abiotic characteristics.
Abiotic Characteristics
Characteristic | In Aquatic environments | In Terrestrial environments | Viscosity – viscosity is a measure of how hard it is to move through a gas or a liquid (fluid) | High viscosity – organisms have to be streamlined | Low viscosity; little resistance to movement | Buoyancy – buoyancy is the amount of support experienced by an object immersed in a liquid or gas. | High buoyancy; organisms do not have to support their bodies as much | Low buoyancy; organisms have to support their bodies with bones and the secondary thickening in plants | Temperature Variation | Less variation in temperature; colder with depth; small bodies of water heat up and cool down faster than larger bodies | Great variation – depends on altitude, location and time of day/year. | Pressure Variation | Increases rapidly with depth | Decreases with altitude | Avaliability of gases. | Quite low – depends on the temperature. Diffusion is slower. | Freely avaliable. Diffusion is rapid. | Avaliability of water. | Rarely a problem in aquatic environments | Varied – depends on location, rainfall, climate, etc. | Avaliaibility of ions | Salwater environments contain 3.5% of dissolved salts. Freshwater environments have low ion concentration. | Ions