L2 Classifying life and reconstructing phylogenies Flashcards
Give an example of taxonomy.
Kingdom - Animalia
Phylum - Chordata
Class - aves(Birds)
Order - Passeriformes (Perching birds)
Family - Fringillidae (finches)
Genus - Geospiza
Species - Geospiza magnirostris
What are the difference in characters of phylogenies of species?
Characters may be:
1. Analogous - similarity due to convergent evolution(Homoplasy)
2. Homologous - Similarity due to common ancestry.
How is the difference in characters classified into?
Synplesiomorphies—shared ancestral characters
Synapomorphies—shared derived characters
Autapomorphies—characters unique to a taxon
What does monophyletic group mean?
Contains the latest common ancestor plus all, and only all, of its descendents
What does paraphyletic group mean?
Diagnosed by plesiomorphies and not including all the descendents of a common ancestor. A paraphyletic group remains after one or more parts of a monophyletic group have been removed.
What does polyphyletic group mean?
A group in which the most recent common ancestor is assigned to some other group and not the group itself. It is defined on the basis of convergence, or by non-homologous characters assumed to have been absent in the latest common ancestor.
What are the eight kingdoms of life?
- Plantae
- Animalia
- Fungi
- Chromista
- Protista
- Archaeozoa
- Archaea
- Bacteria
What are the three domains of life?
Domain Bacteria
Domain Archaea
Domain Eukarya
Which are the multicellular kingdoms?
Which kindoms are unicellular?
Eubacteria (Bacteria): All bacteria are unicellular prokaryotes.
Archaebacteria (Archaea): All archaea are unicellular prokaryotes.
Protista:
Rest are multicellular
What is the difference of organisms represented, cell size, cellular organization and cell walls between eukaryotes and prokaryotes?
- Organisms represented - Bacteria for Prokaryotes , Protists for eukaryotes.
- Cell size - 1 - 10 um for prok, 10-100 um for eukaryotes.
- Cellular orgainsation - Unicellular for prok, multicellular for euk.
- Cell walls - Made of particular sugars and peptides for prok, made of cellulose and chitin for euk.
What is the difference of flagella and cilia between eukaryotes and prokaryotes?
Some have flagella in prok, Euk have cilia or flagella with microtubules.
What is the difference of organelles, metabolism and photosynthesis in eukaryotes and prokaryotes?
- Organelles - No membrane-bound organelles in pro, Membrane-bound chloroplasts and mitochondria in euk.
- Metabolism and photosynthesis - Anaerobic, facultative aerobic in prok, Aerobic in euk.
What is the difference in genetic organization of eukaryotes and prokaryotes?
Genetic organization - Loop of DNA in cytoplasm in prok, DNA in chromosomes within membrane bound nucleus in euk.
What is the difference in reproduction of eukaryotes and prokaryotes?
Reproduction - By binary fission, dominantly asexual but some parasexual in prok, By mitosis or meiosis, dominantly sexual in euk.
When and how were to types of prokaryote identified and differentiated?
In the 1980s it was realized that there were two types of Prokaryote: Eubacteria (Bacteria) and Archaebacteria (Archaea). Archaebacteria are less numerous and diverse than Eubacteria and inhabit extreme environments– thermophiles (very hot) and halophiles (very salty).
How are Eubacteria, Archaebacteria and Eukaryotes related?
- All three domains arose from a common ancestor, highlighting the unity of life.
- Eubacteria and Archaebacteria are prokaryotes with distinct differences in cell wall composition and biochemistry.
- Eukaryotes are characterized by their complex cell structure with a nucleus and organelles.
- Archaebacteria share a more recent common ancestor with Eukaryotes than with Eubacteria.
- Eukaryotic cells likely evolved through endosymbiosis, incorporating prokaryotic ancestors of mitochondria and chloroplasts.
