AP Environmental Science Module Three Lesson Two Overview

Energy Flow through Ecosystems

image of seagull eating a fish with text that reads Energy Flow Through Ecosystems

In an ecosystem there is a one-way flow of energy through the organisms. In this lesson we will explore how energy and nutrients move from one organism to another in an ecosystem.

Objectives and Checklist

By the end of this lesson, you will be able to:

Name and explain the processes of photosynthesis and cellular respiration
Draw food webs and explain how trophic levels are related
Draw and explain the mechanisms of ecological pyramids and biomass pyramids
Calculate NPP and GPP

Key Terms

food web: interweaving food chains
trophic level: the position an organism occupies on the food chain; also called feeding level or energy level
photosynthesis: process that autotrophs use to convert light energy into glucose
aerobic respiration: process of making cellular energy (ATP) using oxygen
anaerobic respiration: process of making cellular energy (ATP) without oxygen, fermentation
energy pyramid (pyramid of productivity): graphical representation of a food chain that shows amount of energy at each level
pyramid of biomass: each bar represents the biomass at each trophic level in the food chain
pyramid of numbers: each bar represents the number of individuals at each trophic level in the food chain
primary productivity: the rate at which producers make energy
net primary productivity: (NPP) is the amount of carbon uptake after subtracting Plant Respiration (RES) from Gross Primary Productivity (GPP)
bioaccumulation: the buildup of substances (usually toxins) over time in the fatty tissue of an organism
biological magnification: increase in the amount of pollutants as one moves up the food chain
primary productivity: The rate of photosynthesis in an area. This rate depends on the amount of sunlight available to producers. In aquatic ecosystems, organisms must depend on sunlight penetrating the water. Organisms closer to the top of the water receive more sunlight. Red light can be absorb down to about 1 meter, and blue light can penetrate the water to a deeper distance (100 meters), but only if the water is very clear. This means that producers in deeper parts of aquatic ecosystems, must find other ways to produce their own food

AP Environmental Science Module Three Lesson Two Overview

Objectives and Checklist

Key Terms

Reference List

Resources

Image Citations

Video Citations