Ecology 101

1. Ecology 101 Energy Transfer

2. The Sun The sun is the source of energy needed for plants to produce their own food. Therefore, it is the source of energy for almost all living things. In this transfer of energy, living things are divided into two categories: autotrophs and heterotrophs.

3. Autotrophs • organisms that can use the energy in sunlight to produce their own food (glucose) • autotrophs are also called Producers because they produce their own food • all food chains start with an autotroph • examples include plants, algae and some bacteria

4. Chemotrophs • autotrophs that get their energy from inorganic substances, such as salt, iron and sulfur • Ex. Bacteria and Deep Sea Worms

5. Heterotrophs • Organisms that do not make their own food • Another term for heterotroph is consumer because they consume other organisms in order to live • There are 5 types of heterotrophs: scavengers, herbivores, carnivores, omnivores and decomposers.

6. Scavengers • – feed on the tissue of dead organisms (both plants and animals); they are also known as detritivores • Ex. – Vultures, Crows, and Shrimp

7. Herbivores • – consumers that feed only on plant material • Ex: cows, elephants, rabbits

8. Carnivore • – consumers that feed only on meat • Ex: sharks, tigers, wolves

9. Omnivore • – consumers that eat both plant and animal material • Ex: bears, raccoons, humans

10. Decomposer • – organisms that consume wastes and dead organisms; they help recycle once-living matter by breaking it down into simple, energy-rich substances. • Ex: fungi and bacteria

11. Energy Transfer • In an ecosystem there is energy, and this is what allows the organisms to live. This energy mainly comes from one original source: the sun. Plants use this solar energy to produce carbohydrates which serves as fuel for living things. When one organism eats another, only some of this energy can be transferred because it has to be used by the organism that was eaten.

12. Conservation of Energy Energy cannot be created or destroyed, it just changes forms.

13. Food Chains • The energy flow from one trophic (feeding) level to the other is known as a food chain • A food chain is simple and direct. It involves one organism at each trophic level

14. Trophic Levels Producer – produce their own food

15. Trophic Levels Producer • Primary Consumer – eats producers

16. Food Chains Producer Primary Consumer Secondary Consumer – eats primary consumers

17. Food Chains Producer Primary Consumer Secondary Consumer Tertiary Consumer – eats secondary consumers

18. Food Chains Tertiary Consumer Producer Primary Consumer Secondary Consumer Decomposer - bacteria and fungi that break down dead organisms and recycle the material back into the environment

19. Food Chains Tertiary Consumer Producer Primary Consumer Secondary Consumer Decomposer

20. Food Webs Interconnected food chains in a community Identify the following: Producers plants Primary Consumers grasshopper, mouse, rabbit, squirrel Secondary Consumers fox, mouse, frog, snake Tertiary Consumers owl, fox Herbivores grasshopper, rabbit, squirrel Carnivores fox, owl, snake, frog Omnivore mouse What element is missing? decomposers

21. Ecological Pyramid Shows the relative amounts of energy or matter contained at each trophic level The Pyramid shows which level has the most energy and the highest number of organisms