Unit 4 Lesson 3: History of Classification Flashcards
taxonomy
the branch of science concerned with naming, classifying, and describing the relationships between all living things on earth
What was Carolus Linnaeus system like
. In this system, each organism is classified within a hierarchy of different groups. The largest groups contain organisms that may share only a few qualities. The Animal kingdom, for instance, held organisms that could move under their own power; the Plant kingdom, organisms that cannot move without outside help.
The smallest groups in the Linnaean system are
genus and species.
An organism’s genus and species make up its
scientific name
Whats humans scientifc name
Humans, for instance, belong to the genus Homo and the species sapiens, so their scientific name is Homo sapiens.
The hierarchies Linnaeus developed look like this (domains were not part of the original scheme. They were added more recently):
- Domain
- Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species
Because a species’ name comes from those smallest two categories, Linnaeus called his system
binomial nomenclature
At the top of the hierarchy, there are only three domains into which all living things can be classified. Whar are these 3 domains
. These are Bacteria, Archaea, and Eukarya.
prokaryotic
a prokaryotic cell is one which does not contain a defined nucleus. Prokaryotes are single-celled organisms, such as bacteria, who do not possess a nucleus
eukaryotic
a eukaryotic cell is one which has a defined cellular nucleus surrounded by a nuclear membrane. Eukaryotic cells can be found in both single- and multi-celled organisms.
What doe sit mean if two organisms are in the same genus
If two organisms are in the same genus, they also share the same domain, kingdom, phylum, class, order, and family.
What was the orginal classification scheme based on
The original classification scheme Linnaeus developed was based strictly on the physical traits of the organism that could be observed.
The original classification scheme Linnaeus developed was based strictly on the physical traits of the organism that could be observed. How did this change
As technology has advanced new evidence has caused many classifications to be reevaluated. DNA evidence has shown that species that were once thought to be closely related are now just distant cousins and some species that were originally not believed to be related at all are now known to be the same species.
stody of the iridescent blue sunburst cerulean-satyr butterfly
an iridescent blue sunburst cerulean-satyr butterfly was identified more than 100 years ago. That brightly colored butterfly lives in close proximity to another butterfly, this one a dull brown. For many years, those were believed to be two entirely different species. After all, they look nothing alike. However, DNA analysis showed that the sunburst cerulean-satyr and its duller neighbor are actually the male and female of the same species. Scientists use this kind of data to create an evolutionary history of an organism.
An organism’s evolutionary history shows to what else it is related and where their common ancestors were in time. What is a common ancestor
an ancestor that two or more descendants hold in common.
phylogenic tree
a diagram that shows the evolutionary relationships between different species that share a common ancestor
The common ancestor evolved and was divided into two families of apes,
family Hylobatidae and family Hominidae.
What id Family Hominidae evolve into
Family Hominidae further evolved into subfamily Ponginae which evolved to be orangutans, and subfamily Homininae which evolved into tribe Gonini, the gorillas, tribe Panini, the chimpanzees and tribe Hominine, humans. The family Homininae are the great apes.
dichotomous key
a tool that allows its user to classify unknown items. When using a dichotomous key, the user observes her item, then describes its characteristics using a series of choices with two possible answers. Each choice leads the user to another step in the key, until her item is identified.
What did Family Hylobatidae evole into
amily Hylobatidae evolved into gibbons, the lesser apes.
What does a phylogenic tree look like
Notice how the common ancestor is located at the bottom. Time moves from the bottom to the top. Also, the branches that are closer together are believed to be more closely related to each other and probably share many traits.
Why do scientists use taxonomy?
Scientists use taxonomy because it makes organizing living things a lot easier. By classifying according to similar traits it allows for relationships between the organisms to be seen.
If two organisms are in the same class how else are they related?
Two organisms in the same class are also in the same domain, kingdom, and phylum.
What is the advantage of using binomial nomenclature?
Binomial nomenclature is the two-word naming system used to classify all life on Earth. By using the organism’s genus and species it removes any question as to which organism is being discussed. This is because only that particular organism has that specific scientific name.
