Dichotomous Keys
What is the purpose of a dichotomous key?
To identify organisms based on observable characteristics.
Name the three domains of life.
Bacteria, Archaea, Eukarya.
What is the broadest level of classification?
Domain
What is the two-part naming system used for organisms called?
Binomial nomenclature
Which kingdom includes multicellular, photosynthetic organisms?
Plants
How many choices are given at each step in a dichotomous key?
Two
Which domain includes all organisms with a nucleus?
Eukarya
What is the most specific level of classification?
Species
What are the two parts of a scientific name?
Genus and species.
Which kingdom includes multicellular organisms that consume food and have no cell walls?
Animals
Give an example of a characteristic that might be used in a dichotomous key.
Body covering, number of legs, presence of wings, etc.
What is the difference between how plants and fungi obtain their food?
Plants make their own food using photosynthesis (autotrophs); fungi absorb decaying food (heterotrophs)
Why do scientists classify organisms?
To organize and understand relationships among living things.
Which part of a scientific name is always capitalized?
Genus
Which kingdom contains organisms that can grow in the dark?
Fungi
Why must characteristics in a dichotomous key be objective?
So different people can identify organisms in the same way.
Which kingdom includes organisms that could be unicellular or multicellular?
Protista
What type of information can scientists use to classify organisms?
Physical traits, DNA, behaviors, reproduction, etc.
Why are scientific names written in Latin?
Latin is universal and does not change over time.
Which kingdom includes organisms that can be plant-like or animal-like and are mostly unicellular?
Protista
Explain why a dichotomous key might need to be updated.
New organisms are discovered or characteristics are reclassified.
What is the difference in how bacteria and protists cells are organized?
Bacteria are prokaryotic; protists are eukaryotic and have membrane bound organelles.
What does it mean when two organisms share many levels of classification?
They are closely related.
Why do scientists prefer scientific names over common names?
Common names vary; scientific names are consistent worldwide.
Which kingdom contains organisms that are prokaryotic and found in many non-extreme environments?
Bacteria