The concept of the biosphere

• the biosphere is where life exists and includes the lithosphere (soil and rocks), hydrosphere (water), and atmosphere (gases).
  • it also includes all living organisms and dead organic matter.
  • there are many different kinds of living things including plants, animals and micro-organisms.
  • all living things can carry out all the seven life processes: nutrition (feeding), growth, reproduction, respiration (energy production), excretion, sensitivity (to the environment) and movement.

• Greet the learners.
• Hold up a picture of the earth or show a model of the globe to the learners.
  • Ask them what they can remember from what they have learnt about planet earth in Grade 6.
  • Tell them that they are going to have a competition to see which group can come up with the most facts about the earth.

• Divide learners into groups of 5 or 7 (depending on the size of the class).
• Allow the groups 5 minutes to come up with as many facts about the earth as they can. Appoint a scribe in each group to write down the facts.
• After 5 minutes obtain feedback and write key facts on the board.
• Hand out prizes or afford a special privilege to the winning group.

• Present an overview of what learners learnt about Planet Earth in Grade 6 by using PRESENTATION 1: Planet Earth to refresh learners’ knowledge of the previous year’s work.
• Tell learners that organisms or living things are found in almost every place on the Earth’s surface. They are found in the air, in water and on land.
• In order to survive, organisms need access to water, air, food, space, favourable temperatures and protection from enemies.
• Organisms can only survive in environments that meet their needs.
• Ask learners if they have ever heard of the “Biosphere”? Tell them that today’s lesson is all about this topic.
• Present an overview of the Biosphere by using PRESENTATION 2: The Biosphere (Part 1).

Show VIDEO CLIP 1: Introduction to Ecology (4.46 min.). 

In this video, learners will learn more about the biosphere, ecosystems, communities, populations, organisms, habitats, niches, generalists, specialists, biotic and abiotic factors. 

• Hand out WORKSHEET A for learners to complete.
• After completion, go over the answers to ensure that the learners have the correct information. (Refer to WORKSHEET A MEMORANDUM).

• Tell learners that we know that the biosphere is all about life, but how do we know that an organism is actually alive? We will find out in the next presentation.
• Present the second part of the topic by using PRESENTATION 3: The Biosphere (Part 2).
• Show VIDEO CLIP 2: Mrs Gren (2.13 min.).
• Show VIDEO CLIP 3: The seven Life Processes (3.12 min.).