Unit 7: Ecology

1. Unit 7: Ecology

2. Energy Flow Unit 7: Ecology Chapter 3-2

3. Energy • The relationship between organisms interaction with their environment is based on energy needs • The SUN is the main energy source for life on Earth

4. Producers • Autotrophs: capture energy from sunlight or chemicals and use it to make their own food • Because they make their own food, they are also called PRODUCERS • Ex: plants, bacteria, algae

5. Two ways producers make their own food • Photosynthesis: autotrophs use light energy (sun) to make food 6CO2 + 6H2O  C6H1206 + 6O2 • Carbon dioxide + water  carbohydrates + oxygen

6. During photosynthesis, Sugar (C6H12O6 ) is produced inside the chloroplasts by combining Carbon Dioxide (CO2) and Water (H2O). CO2 + H2O + light energy  C6H12O6 + O2 Energy from sunlight is used by the chloroplasts to produce sugar. Carbon dioxide enters the plant through the stomata. CO2 O2 Plants need oxygen as well. At night, respiration occurs. Respiration is a process by which the plant releases carbon dioxide and lets oxygen into its cells. The plant produces oxygen during photosynthesis. The oxygen gas escapes through the stomata. Legend Carbon dioxide (CO2) Oxygen (O2) Water (H20) Light energy The plant combines water and carbon dioxide to form sugar. The water is taken up by the plants root.

7. Chemosynthesis: autotrophs convert energy stored in inorganic compounds into food • Ex: bacteria http://www.pmel.noaa.gov/vents/nemo/education/curr_p1_12.html

9. Consumers • Heterotrophs: rely on other organisms for their energy and food supply • Because they eat other organisms, they are CONSUMERS • EX: animals, fungi, & insects

10. Autotroph of Heterotroph? • Palm tree • Tree Frog • Black Bear • Phytoplankton (Energy from sun) • Grass • Wild mushroom

11. 5 Types of consumers • 1. Herbivore: eats plants • a) Ex: rabbit • 2. Carnivore: eats meat • a) Ex: fox • 3. Omnivore: eats both meat & plants • a) Ex: Bear

12. 4. Detritivore: eat plant/animal remains or dead matter • a) Ex: earthworms or snails • 5. Decomposer: breaks down organic matter • a) Ex: bacteria or fungi

13. Which type of heterotroph? • Tree snake (Eats mice, frogs, insects) • Sea urchin (Eats seaweed) • People • Mushroom (Dead plants and animals)

14. Feeding Relationships • How energy travels through an ecosystem. • Food Chain: diagram showing the transfer of energy from one organisms eating another.

15. EX: Algae is eaten by krill, krill is eaten by cod, cod is eaten by seal, seal is eaten by killer whale

17. Food Web: the combination of ALL possible food chains in an ecosystem

18. Grazing & Detrital Food Webs

19. Identify one food chain in this food web. Share it with your partner!

20. Trophic Levels • Trophic Level: (feeding level) Each step in a food chain or web. • First Trophic Level: • producer / autotroph • Second Trophic Level: • Primary consumer /herbivore

21. Third Trophic Level: • Secondary Consumer • carnivore or omnivore • Forth Trophic Level: • Tertiary Consumer • carnivore or omnivore

24. Can you identify the trophic level? • Which trophic level is the krill? • Which trophic level is the leopard seal? • Which trophic level is the algae?

25. Energy Pyramid • Energy pyramid: a diagram that shows the amount of energy in each trophic level of a food chain or web • Only 10% of the energy at one trophic level is transferred to the next level • The rest of the energy is lost as HEAT

26. The result is that there must be many more producers than consumers

27. Pair Share • Why are there many more producers than consumers? How much energy gets passed from one trophic level to the next?

28. Biomass Pyramids • Diagram that shows the amount (in grams) of potential food available for each trophic level • Because of the loss of energy at each trophic level, there is usually a larger mass of living tissue at the lower levels than at the upper levels