TOPIC: ENERGY FLOW

WHAT NEEDS TO BE COVERED

• Most ecosystems rely on a supply of energy from sunlight.
• Light energy is converted to chemical energy in carbon compounds by photosynthesis.
• Chemical energy in carbon compounds flows through food chains by means of feeding.
• Energy released from carbon compounds by respiration is used in living organisms and converted to heat.
• Living organisms cannot convert heat to other forms of energy.
• Heat is lost from ecosystems.
• Energy losses between trophic levels restrict the length of food chains and the biomass of higher trophic levels.

• Quantitative representations of energy flow using pyramids of energy.

• Pyramids of number and biomass are not required. Students should be clear that biomass in terrestrial ecosystems diminishes with energy along food chains due to loss of carbon dioxide, water and other waste products, such as urea.
• Pyramids of energy should be drawn to scale and should be stepped, not triangular. The terms producer, first consumer and second consumer and so on should be used, rather than first trophic level, second trophic level and so on.
• The distinction between energy flow in ecosystems and cycling of inorganic nutrients should be stressed. Students should understand that there is a continuous but variable supply of energy in the form of sunlight but that the supply of nutrients in an ecosystem is finite and limited.
• The energetics of food chains is a factor in the efficiency of food production for the alleviation of world hunger.

TOPIC :SPECIES,COMMUNITY ECOSYSTEM

WHAT NEEDS TO BE COVERED

• Species are groups of organisms that can potentially interbreed to produce fertile offspring.
• Members of a species may be reproductively isolated in separate populations.
• Species have either an autotrophic or heterotrophic method of nutrition (a few species have both methods).
• Consumers are heterotrophs that feed on living organisms by ingestion.
• Detritivores are heterotrophs that obtain organic nutrients from detritus by internal digestion.
• Saprotrophs are heterotrophs that obtain organic nutrients from dead organisms by external digestion.
• A community is formed by populations of different species living together and interacting with each other.
• A community forms an ecosystem by its interactions with the abiotic environment.
• Autotrophs obtain inorganic nutrients from the abiotic environment.
• The supply of inorganic nutrients is maintained by nutrient cycling.
• Ecosystems have the potential to be sustainable over long periods of time.

• Skill: Classifying species as autotrophs, consumers, detritivores or saprotrophs from a knowledge of their mode of nutrition.
• Skill: how can a sealed mesocosms be set up to establish sustainability.
• Skill: Testing for association between two species using the chi-squared test with data obtained by quadrat sampling.
• Skill: Recognizing and interpreting statistical significance.

• Mesocosms can be set up in open tanks, but sealed glass vessels are preferable because entry and exit of matter can be prevented but light can enter and heat can leave. Aquatic systems are likely to be more successful than terrestrial ones.
• To obtain data for the chi-squared test, an ecosystem should be chosen in which one or more factors affecting the distribution of the chosen species varies. Sampling should be based on random numbers. In each quadrat the presence or absence of the chosen species should be recorded.

TOPIC: CLIMATE CHANGE

WHAT NEEDS TO BE COVERED

• Carbon dioxide and water vapour are the most significant greenhouse gases.
• Other gases including methane and nitrogen oxides have less impact.
• The impact of a gas depends on its ability to absorb long wave radiation as well as on its concentration in the atmosphere.
• The warmed Earth emits longer wavelength radiation (heat).
• Longer wave radiation is absorbed by greenhouse gases that retain the heat in the atmosphere.
• Global temperatures and climate patterns are influenced by concentrations of greenhouse gases.
• There is a correlation between rising atmospheric concentrations of carbon dioxide since the start of the industrial revolution 200 years ago and average global temperatures.
• Recent increases in atmospheric carbon dioxide are largely due to increases in the combustion of fossilized organic matter.

• Application: Threats to coral reefs from increasing concentrations of dissolved carbon dioxide.
• Application: Correlations between global temperatures and carbon dioxide concentrations on Earth.
• Application: Evaluating claims that human activities are not causing climate change.

• Carbon dioxide, methane and water vapour should be included in discussions.
• The harmful consequences of ozone depletion do not need to be discussed and it should be made clear that ozone depletion is not the cause of the enhanced greenhouse effect.

TOPIC :CARBON CYCLING

WHAT NEEDS TO BE COVERED

you are supposed to complete your presentation by 29/8/15.your presentation should be for 30 -35 mnts.

question answer session for 10-15 mins

each group to select one leader who further subdivides the topic

would prefer inquiry based approach with less input from the teacher but in case of doubt you are welcome to discuss

each student needs to be actively involved in the process

gather information from different sources don't forget to cite it.

be as innovative as possible in presenting the idea

can use technology,creative charts to display ideas .

• you score higher for
  
• sharing of ideas
  
• coverage of contents
  
• innovation in presentation
  
• confidence of speakers
  
• ability to handle questions