Patterns in Life: Diversity and Classification

Living things are grouped by shared features: five kingdoms, plant and animal groups, the levels of classification and two-part scientific names.

Key ideas

• Whittaker’s five kingdoms: Monera (no true nucleus), Protista (single eukaryotic cells), Fungi, Plantae, Animalia.
• Plants: Thallophyta (no true body parts), Bryophyta (no vascular tissue), Pteridophyta (vascular, no seeds), gymnosperms (naked seeds), angiosperms (seeds in fruits).
• Animals without a backbone include Porifera, Cnidaria, Platyhelminthes, Nematoda, Annelida, Arthropoda, Mollusca and Echinodermata.
• Vertebrates: fish, amphibians, reptiles, birds and mammals; birds and mammals are warm-blooded.
• Classification uses body features, not habits: a bat is a mammal and a whale is not a fish.
• A dichotomous key identifies organisms by questions with two choices each.

Remember

Watch out

• Writing the species name with a capital letter, or the genus with a small one.
• Grouping a spider with insects (it has eight legs; insects have six).
• Placing mushrooms with plants (fungi cannot make their own food).

Worked example