In this Grade 7 Life Science lesson from Chapter 9, students explore protists as the most diverse group of organisms, examining specific examples such as algae, diatoms, euglena, and slime molds. Students learn how protists are classified by their three methods of obtaining energy: photosynthesis, consuming other organisms, and absorbing nutrients from their environment. A hands-on microscope investigation of pond water reinforces direct observation of these single-celled and multicellular organisms in their natural habitat.
Section 1
Protists Power Ecosystems in Three Ways
Protists obtain energy through capturing sunlight like plants, consuming other organisms like animals, or absorbing nutrients from their surroundings like fungi. Some protists can even switch between methods.
Section 2
Algae Transform Sunlight into Energy
Plantlike protists called algae use photosynthesis to create energy from sunlight. They contain chlorophyll, release oxygen, and exist as both single-celled organisms and multicellular forms like seaweed.
Section 3
Protozoa Hunt and Consume Other Organisms
Animal-like protists called protozoa obtain energy by eating other organisms. They move using structures like cilia or flagella to capture food, while some, like parasites, cause diseases in humans.
Section 4
Molds Break Down Decaying Matter
Fungus-like protists act as decomposers by absorbing nutrients from decaying materials. Water molds, slime molds, and plasmodial slime molds each have unique structures and life cycles in moist environments.
Section 5
Scientists Classify Diverse Protists by Habitat
Protists live in various moist environments including freshwater, saltwater, and forest floors. Some float freely, others attach to surfaces, making them the most diverse kingdom with both single-celled and multicellular forms.
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Section 1
Protists Power Ecosystems in Three Ways
Protists obtain energy through capturing sunlight like plants, consuming other organisms like animals, or absorbing nutrients from their surroundings like fungi. Some protists can even switch between methods.
Section 2
Algae Transform Sunlight into Energy
Plantlike protists called algae use photosynthesis to create energy from sunlight. They contain chlorophyll, release oxygen, and exist as both single-celled organisms and multicellular forms like seaweed.
Section 3
Protozoa Hunt and Consume Other Organisms
Animal-like protists called protozoa obtain energy by eating other organisms. They move using structures like cilia or flagella to capture food, while some, like parasites, cause diseases in humans.
Section 4
Molds Break Down Decaying Matter
Fungus-like protists act as decomposers by absorbing nutrients from decaying materials. Water molds, slime molds, and plasmodial slime molds each have unique structures and life cycles in moist environments.
Section 5
Scientists Classify Diverse Protists by Habitat
Protists live in various moist environments including freshwater, saltwater, and forest floors. Some float freely, others attach to surfaces, making them the most diverse kingdom with both single-celled and multicellular forms.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter