SECTION 3.3 ENERGY FLOW IN ECOSYSTEMS

DO NOW

• REBUS PUZZLES ON THE BOARD

LAST NIGHT’S HOMEWORK

• Read Section 3.3 and define:• Food chain• Phytoplankton• Food web• Zooplankton• Trophic level• Ecological pyramid• Biomass

HOMEWORK

• Pg. 78• Answer questions 1a, 1b, 2a & 2b in the Section

3.3 Assessment

•Primary producers – give an example?•Grass, trees, bushes – anything that produces its own food. Typically through photosynthesis.•Known as Autotrophs•Store energy in forms that other organisms can use when eaten

REVIEW

•Consumers aka Heterotrophs•You are one, you rely on eating off of something else even if you are a vegetarian.•Some are specialized – Lions only eat meat. Others are generalized – bears can eat fish or plants / berries.

REVIEW

•Chemosynthesis with equation

REVIEW

NEW MATERIAL

• FOOD CHAIN – series of steps in which organisms transfer energy by eating and being eaten.• Primary Producer Herbivore Carnivore (pg. 73)

• FOOD WEB – Network of feeding interactions• Herbivores graze on different types of grass• Carnivores feed on different herbivores (pg. 74)

FOOD CHAINS

• One-way stream• Primary producer various consumers

• Food chains vary in length• As little as 2 steps but could be much larger

ACTIVITY!

• Find a partner• Write a story starting from a primary producer.• The story should be written so that there are at

least 3 animals involved• Trade stories with partner and partner draws the

food chain at the bottom of the page• Most creative story wins a prize

FOOD WEB

• More complex than a single, simple chain• Herbivores graze on several types of grasses, and

carnivores or omnivores eat herbivores.• Why are food chains a more accurate

representation of the feeding relationship?

HOMEWORK

• Pg. 78• Answer questions 1a, 1b, 2a & 2b in the Section

3.3 Assessment