8.7 3.1.8 summary

Summary

Biosphere:

The biosphere is the region of the earth that encompasses all living organisms: plants, animals and bacteria. The biosphere includes the outer region of theearth (the lithosphere) and the lower region of the atmosphere (the troposphere) as well as the lakes, oceans, streams, ice and clouds comprisingthe earth's water resources (hydrosphere).

Lithosphere:

The layer of the mantle above the atmosphere plus the entire crust make up a region called the lithosphere.

Hydrosphere:

The Hydrosphere contains all the water on Earth. As groundwater, the hydrosphere penetrates the soil as far down as bedrock. It is found in aquifers asgroundwater and also between soil particles. As surface water, it is found in wetlands, marshes, estuaries, lakes, streams, rivers, lakes, seas, and oceans.In the atmosphere, water is found as a gas throughout the different regions.

Atmosphere:

The gaseous layer that surrounds the earth. It extends outward to about 1,000 kilometers where it transitions to interplanetary space.

Biomes Biomes are, the categories into which ecologists organise similar communities of plants, animals, and the environmental conditions in which they live. The fourmajor types of biomes are aquatic, grasslands, forests, and desert. Aquatic biomes are probably the most important of all the biomes. Their medium, water,is a major natural resource.

The distribution of plants and animals around the world is anything but random. Instead, it is a result of the interplay of individual environmental tolerancesof species and the environmental conditions, especially variations in temperature and precipitation. These interactions result in

Enviroment

In this unit we explore the different abiotic and biotic factors that interact or the relationships within an ecosystem. Also we have included a variety ofpossible investigations and activities to explore each factor within any given ecosystem.

Energy flow

In this unit, you have learnt that organisms get their energy either directly or indirectly from the sun.

All organisms fit together in a complicated food web depending on whether they supply energy or get energy from each other. Food webs are made up of foodchains that show the flow of energy from producers (plants) to consumers (animals) to decomposers (bacteria).

The flow of nutrients between the atmosphere and organisms is called nutrient cycling.The four important cycles for life on earth are the water, carbon,oxygen and nitrogen cycles.