Overview of Section Resources

Section 1: Observing Daphnia
To introduce students to aquatic habitats, students begin an aquarium log, to be used to record changes in water depth and changes in populations throughout the module. Students then use appropriate technology to observe daphnia, one type of aquatic organism. They also begin a population study of daphnia.
Section 2: Population Changes
Students continue the population study of daphnia, estimating, predicting, and recording population changes. Students discuss factors that affect populations, including availability of food and space. Students also do a simple experiment to determine the type of food preferred by daphnia.
Section 3: Observing Aquatic Organisms
In this section, students add more organisms to their aquariums, including anacharis, duckweed, and snails. Students make careful observations of the structures of these organisms and relate structure to function. Students also begin a drawing of their aquarium, illustrating the different organisms. In addition, students investigate the process of photosynthesis and communicate their results.
Section 4: Guppies
Students continue to add organisms to their aquariums and to record changes in populations. They examine the characteristics of guppies and make additions to their aquarium drawings. Students also explore interactions among living things, including predator/prey relationships.
Section 5: The Food Web
Students continue to track population changes in their aquariums and add newts to the freshwater habitats. Students also investigate food chains and food webs, using models to illustrate the flow of energy from one organism to another. They also investigate fossils, comparing fossil replicas to the structures of modern organisms.
Section 6: Water Pollution
Students explore the effects of pollution on aquatic habitats. They test the pH levels of various chemicals and infer how acid rain might affect aquatic ecosystems. They also investigate an algae bloom, conducting an experiment to determine which chemicals are catalysts for algae growth. Students then investigate the effects of different chemicals on seed germination.