1. Classification

2. Cell Types Cells come in all types of shapes and sizes.
Cell Membrane – cells are surrounded by a thin
flexible layer
Also known as a plasma membrane
Eukaryotes – are cells that enclose their DNA in
nuclei
Prokaryotes – are cells that do not enclose DNA in

3. Cell Types Eukaryotic cells have the ability to specialize
Have a specific function in a multicellular organism
This gives rise to multicellular and more complex organisms

4. Cell Types Prokaryotic cells do not have the ability to specialize
This limits their ability to form multicellular organisms
Prokaryotes also need to rely on outside sources to feed
Eukaryotes have the ability to in some cases manufacture food.
Eukaryotes have the ability to break down larger molecules for food

5. Taxonomy and Evolution
Taxonomy – (a branch of Biology) involves the
identification, naming, and
classification of species
To reduce confusion in discussing organisms
One goal of taxonomy is to assign a universal scientific name to each known species
Systemics – the science of naming things
Taxon – the groups that systematics organize
living organisms in

6. Binomial Nomenclature
Each species is assigned a two part scientific name
Scientific names are written in italic
First word begins with a capital letter
Genus
Second word is lowercase
Species (can interbreed and form fertile offspring)

7. The Linnaean System of Classification
Originally had only 4 groups now there is 6
Developed by botanist Carolus Linnaeus ( )

8. The Linnaean System of Classification
Groups of similar (genera – plural of genus) in the same family
Families placed in orders
Orders into Classes
Classes into Phyla
Phyla are grouped into Kingdom

10. Modern Evolutionary Classification
Phylogeny – the evolutionary history of lineages
The goal of phylogenetic systematics, or evolutionary classification, is to group species into larger categories that reflect lines of evolutionary descent, rather than overall similarities and differences

11. Molecular Data as a Taxonomic Tool
Relatedness is measured by comparing genes and gene products (proteins)
The more sequences match, the closer they are related.
Molecular data is independent of structural data
Structural is a traditional method
Accuracy will depend on molecular data supported by structural data
Fossil data supports:
Whales are closely related to Hippos, pigs, camels…. Supported by molecular data

12. Phylogenetic Trees DNA began a new era in Taxonomy in the 1960’s
Along with computers
The pattern of branches can tell you how closely related species are
The deeper the “split” the further “away” the two species are from each other
The closer the “split” the more related

14. Phylogenetic Trees
Clade – each evolutionary branch in a polygenetic tree
A group of species that include a single common ancestor
Clades can nest within larger clades
Each item in a clade may be an individual species genus, a family or other taxonomic group

15. Cladistics Method mostly used today
Key rule: all organisms of a clade share homologous structures that do not occur outside the clade
Derived Characters – unique features that unite the
organisms as a clade
Cladogram – links groups of organisms by showing how
evolutionary lines, or lineages, branched off
from common ancestors.

16. Cladistics
Monophyletic Group – includes a single common ancestor and all its descendants

17. Building A Cladogram Refer to page 517
Speciation event – when one ancestral species
splits into 2 new ones.
This is the basis of each branch point or node
The node represents the last point which the 2 lineages shared a common ancestor
The bottom or “root” of a cladogram represents the common ancestor shared by all of the organisms in the cladogram

18. Building A Cladogram
A cladogram’s patterns degrees of relatedness among organisms

19. Building A Cladogram
Derived Character – A trait that arose in the most recent common ancestor of a particular lineage and was passed along to their decedents.

20. In your Composition Book
Quick Lab
Page 520
Answer all questions

21. DNA in Classification
All organisms carry genetic information in their DNA
Passed on from earlier generations
Many different organisms share many genes and show important homologies that can be used to determine evolutionary relationships
Using DNA has made evolution more accurate

22. Molecular Clock
Method used by researchers that uses mutation rates in DNA to estimate the length of time that 2 species have been evolving independently
ACGGTTCTAC
ACGGTACAAC
CCGGTTCAAC
ACGGTTCAAC
ATGGTTGAAC
ATGGTTGAAC

23. Six Kingdom Scheme Early taxonomy began with two Kingdoms Plants
Animals
Then went to three
Animal
Protozoa
5 Kingdoms:
Monera
Protista
Fungi
Plantae
Animala
1700’S
Still inadequate
1800’S

24. Consists of multi cellular eukaryotes
Six Kingdom Scheme
Scheme places prokaryotes (bacteria) in the kingdom Monera
4 Kingdoms are:
Eukaryotes
Plants
Fungi
Animals
Among Eukaryotes Kingdoms differ in structure development, and modes of nutrition.
Plants Photosynthesis
Fungi - decompose
Consists of multi cellular eukaryotes

25. Six Kingdom Scheme
Eubacteria
Archaebacteria
Protist
Fungi
Plantae
Animalia