Section 1
Scientists Organize Living Things Into Six Kingdoms
Scientists classify organisms into six kingdoms—animals, plants, fungi, protists, and two bacteria kingdoms—based on traits like cell structure, number of cells, and how they get food.
In this Grade 4 lesson from Science: A Closer Look, students learn how scientists classify living things using traits such as cell structure, number of cells, presence of a nucleus, food source, and movement. Students explore the six kingdoms — ancient bacteria, bacteria, protists, fungi, plants, and animals — and discover how organisms are further grouped into phylum, class, order, family, genus, and species. Hands-on sorting activities help students understand how shared characteristics form the basis of biological classification.
Section 1
Scientists Organize Living Things Into Six Kingdoms
Scientists classify organisms into six kingdoms—animals, plants, fungi, protists, and two bacteria kingdoms—based on traits like cell structure, number of cells, and how they get food.
Section 2
Biologists Break Kingdoms Into Smaller Groups
After kingdom, organisms are classified into increasingly specific groups: phylum, class, order, family, genus, and species. Each smaller group contains organisms with more similarities.
Section 3
Microorganisms Populate Three Different Kingdoms
Single-celled microorganisms include bacteria (without nuclei), fungi (which cannot make their own food), and protists (with cell nuclei). Some help us, while others cause diseases.
Section 4
Scientists Name Organisms Using Two-Part System
Every organism receives a scientific name consisting of its genus (shared with related organisms) and species (unique to its kind), helping scientists identify and study specific living things.
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Section 1
Scientists Organize Living Things Into Six Kingdoms
Scientists classify organisms into six kingdoms—animals, plants, fungi, protists, and two bacteria kingdoms—based on traits like cell structure, number of cells, and how they get food.
Section 2
Biologists Break Kingdoms Into Smaller Groups
After kingdom, organisms are classified into increasingly specific groups: phylum, class, order, family, genus, and species. Each smaller group contains organisms with more similarities.
Section 3
Microorganisms Populate Three Different Kingdoms
Single-celled microorganisms include bacteria (without nuclei), fungi (which cannot make their own food), and protists (with cell nuclei). Some help us, while others cause diseases.
Section 4
Scientists Name Organisms Using Two-Part System
Every organism receives a scientific name consisting of its genus (shared with related organisms) and species (unique to its kind), helping scientists identify and study specific living things.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter