1. Topic 4
How organisms react

2. An Ecosystem

3. An Ecosystem Biotic – the living things in the ecosystem.
Abiotic –the non living things in an ecosystem.
How does a hare interact with biotic and abiotic parts of its ecosystem?

4. List 5 biotic and abiotic parts of the ecosystem shown

5. Roles of Organisms A NICHE is the role of an organism in an ecosystem:
What it eats
What eats it
Where it lives
How it interacts with other animals (symbiosis)

6. Roles of Organisms Producers vs. Consumers
Producers photosynthesize, and use carbon dioxide, water, and the sun’s energy to produce glucose (food) and oxygen. Photosynthesis
Consumers- Eat other living things for energy and breathe our carbon dioxide.

10. Roles of Organisms Consumers may also be: Some Consumers will be:
Herbivores – plant eaters
Carnivores – meat (other consumers) eaters
Omnivores – eat plants and animals (other consumers)
Some Consumers will be:
Predators – do the eating
Prey – Are eaten by predators

11. Name an organism for each niche:
Producers
Consumers
Herbivores
Carnivores
Omnivores
Predators
Prey

12. Food Chains
Food Chains show how stored energy passes from organism to organism
What direction do the arrows point to?

14. Create a Prairie Food Chain:

16. Pyramid of Numbers
Shows the organisms of a food chain but represents the number of organisms to meet the energy needs of the next level

18. Biomass
Biomass- is the total mass of all the organisms in an ecosystem.
Bio mass can also be represented in a pyramid form.
Why?

19. Scavengers and Decomposers
Scavengers eat and live off of dead organisms and wastes.

20. Scavengers and Decomposers

21. Scavengers and Decomposers
Decomposers- Are small organisms that live on or in dead materials to absorb nutrients
They recycle dead organic matter back to the earth
Bacteria and fungi
Worms
Maggots
Insects

22. Did you know?
Right now trillions of bacteria are decomposing your body, by growing on your skin, and are constantly breaking dead skin cells down into common household dust?

23. Composts Composts are a way to speed up natural decomposition
Many kitchen wastes can be broken down in a compost
Small bacteria break down the wastes into nutrient rich soil called top soil

24. Topic 5
Cycles in the Environment

25. Carbon Foot Print
Burning of fossil fuels that contain carbon is linked to global climate because it produces carbon dioxide, a greenhouse gas.

26. The Carbon Cycle
All living things are made from carbon – it is necessary for life to exist.
Plankton are microscopic plants and animals
Phytoplankton are microscopic plants
Zooplankton are microscopic animals.
Decomposing plankton under pressure can be converted to fossil fuels.
Fossil fuels contain carbon.

27. The Carbon Cycle
Plants use carbon dioxide to make glucose or sugar which also contain carbon that we eat from plants.
Our bodies tissues are made from carbon as well, and when we eat other animals we convert that carbon into tissues like muscles.
We also breathe out carbon dioxide
As living organisms die and break down the carbon breaks down and changes form.

29. Carbon constantly changes form and cycles through the environment

30. The Water Cycle All living things need water. We are 70% water. Water:
Helps to break down food for energy
Makes up much of our cells
Carries away waste
Water Cycle

32. Water Cycle
The water cycle is the continuous movement of water through an ecosystem.
Water cycles as:
Evaporation- liquid to gas
Transpiration- liquid to gas but by plants (tree sweat)
Condensation- gas to liquid (clouds)
Precipitation – gas to liquid but as rain or snow
Ground water and run-off contribute to the movement and cycle of water too

34. Pollution and the Environment
Pollution- occurs when a substance added to the environment cannot be broken down, stored or recycled by the air, land or water to be converted to non damaging forms.
If pollution gets too high it harms organisms.
Pollutants- are substances that cause pollution.
Carbon dioxide is natural but burning fossil fuels has caused it to accumulate in the atmosphere.

36. Pollution – Acid Rain
Sulfur and nitrogen come from burning coal and fossil fuels, as well as from our cars.
These produce too much sulfur and nitrogen.
When sulfur and nitrogen mix with water in the atmosphere the rain becomes acidic.
When this rain falls and damages crops, corrodes metals, and is especially toxic to fish eggs.
If the pH falls below 5.6 many of the organisms in a lake will die.

37. The Statue of Liberty

38. pH scale

39. Pollution PCB’s (Polychlorinated Biphenyls) Mercury
Used to cool power lines
Used in paints
PCB’s have shown up in our water
They are toxic and are linked to cancer
They can contaminate soil and water for decades.
Mercury
Use in gold mining and other industries like pulp and paper.
Cause severe nerve damage in humans and other animals.
Causes brain damage

40. Pollution – Mercury

41. Pollution - DDT Was a very effective pesticide
Banned in the 80’s when it was linked to the weakening of eggs of large birds like the bald eagle.
Not water soluble
No known toxic effects in humans.

42. Pollution – Bioaccumulation
Bioaccumulation (biomagnification)
Toxins become more and more concentrated as you move up the food chain.
Why does this happen?