UNIT 1 – CLASSIFICATION & KINGDOMS
Chapter: / Name: Date: Block:People/Vocabulary/
Main Ideas/Images / Objectives/Notes/
Definitions/Examples/Sketches
Section 18-1 / Objectives:
Finding Order in Diversity
Why Classify?
Assigning Scientific Names
- Early Efforts at Naming Organisms
- Binomial Nomenclature
Why Classify?
There is a vast abundance of plants and animals on earth; therefore we must ______them in a logical way according to ______biological meaning. The process of ______classifies organisms into several categories.
Assigning Scientific Names
Early Efforts:Describing the organism’s ______characteristics in great detail. Ex: four legged mammal with hooves, hair, upright ears, and is vegetarian. This had a major drawback! This animal could be anything…
Binomial Nomenclature
1800’s Carolus______, a Swedish botanist developed a two-word universal naming system called ______Nomenclature. Each species is given a ______-part scientific name. The first word is capitalized, and both words are written in italics. First word = Genus, second word = species
/ Linnaeus’s System of Classification
In taxonomy, a group or level of organization is called a taxonomic category or ______(plural: taxa).There are 7 taxonomic levels; the two most specific are genus and species.
- Kingdom: Linnaeus named the first two kingdoms Animalia and Plantae. This is the largest level!
- Phylum: Groups organisms by their body characteristics, ex: chordata (has a back bone)
- Class: By type of animal, ex: carnivore (meat eater), herbivore (plant eater).
- Order: an additional level between class and family.
- Family: groups of similar plants/animals, ex: canidae or felidae (dogs and cats).
Summary of 18-1:
Section 18-2 / Objectives:
Modern Evolutionary Classification
Problems With Traditional Classification
Evolutionary Classification
Classification Using Cladograms
Similarities in DNA & RNA
- Molecular Clocks
Problems with Traditional Classification
In the 1800’s Linnaeus classified organisms into categories by their ______(body structure).
How might have he classified dolphin? They have fins, no fur, and lives in the ocean. Would he think dolphins were fish? Dolphins are actually classified as mammals: they’re warmblooded, breathe air, and give birth to live young. Fish don’t do that!
Both examples (dolphin and crabs) point out problems faced by taxonomists who relied on body structure comparisons.
______Evolution causes organisms that are very different to evolve similar bodies when living in ______conditions.
- These similarities can make it difficult to classify them.
Evolutionary Classification
Darwin’s theory of evolution showed that animals ______traits because they share an evolutionary history. Biologists now group organisms into categories that represent lines of evolutionary descent, not just physical similarities. Ex: species in the same genus should be ______closely related to one another than to a different species under a different genus.
/ Classification Using Cladograms
Many biologists use cladistic______to identify and consider only characteristics of organisms that are evolutionary innovations (helpful differences). Characteristics that appear more ______in time are called derived characteristics. Derived characteristics are used to construct a ______(diagram showing evolutionary relationships among a group of organisms.
Similarities in DNA & RNA
All life has ______info that is passes on by DNA or RNA.
The genes of many organisms can show similarity at the molecular level. These similarities are used to determine classification.
- More similarities in DNA = ______related
Molecular Clocks
Comparisons of DNA can also be used to mark the passage of evolutionary ______. Molecular Clocks use DNA comparisons to establish the length of time that two species have been evolving independently. As species evolve (become different), they develop mutations (changes in DNA). More mutations = ______related.
Summary 18-2:
Section 18-3 / Objectives:
Kingdoms and Domains
The Tree of Life Evolves
The Three-Domain System
Using a Dichotomous Key
The Tree of Life Evolves
During Linnaeus’s time, ______was known about the living world, Linnaeus said their were only _____ types of living things: plants and animals.Plants were green and photosynthetic; they used energy from the _____ to make their own food. And animals were mobile and consumed food for energy.
- As scientists learned more about the natural world, they realized that Linnaeus’s system didn’t represent all living things on earth. There were bacteria, mushrooms, yeast, and other ______; which were placed in a kingdom called Monera.
- As research continued, Monera was split into ____ kingdoms: Eubacteria and Archaebacteria.
The Three-Domain System
As scientists use DNA evidence to help classify organisms, they developed a more inclusive category called ______.
- There are 3 domains: Bacteria, Archaea, and Eukarya.
Using a Dichotomous Key
How can you chose organisms to fit in all those categories?!
Dichotomous Keys use ______statements that describe physical characteristics of different organisms.
- Choosing one statement will lead you to the next, and so on, until you determine the organism’s ______.
Summary 18-3:
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