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Biology AS Level Unit 2 > Evolutionary History > Flashcards

Flashcards in Evolutionary History Deck (38)
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1

Definition of phylogenetic classification

Grouping organisms together to reflect evolutionary history, closely related organisms grouped together. Groups have a more recent common ancestor so will share physical properties

2

Phylogenetic tree

Branch points represent common ancestors of organisms in branches above

3

Taxa are..

Levels of classification

4

Classification order

Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species

5

Largest taxon?

Domain

6

3 types of Domain

Eubacteria
Archaea
Eukaryota

7

Eubacteria

Prokaryotes, familiar bacteria like e.coli and salmonella

8

Archaea

Prokaryotes, bacteria with unusual metabolisms, 'extremophiles'

9

Eukaryota

Eukaryotes like plantae, fungi, animalia, protoctista

10

5 types of Kingdom

Prokaryota
Protoctista
Animalia
Plantae
Fungi

11

Prokaryota

Bacteria/Cyanobacteria, microscopic, single called organisms with no membrane bound organelles , prokaryotes with murein/peptidoglycan cell walls

12

Protoctista

Eukaryotes, unicellular, can be multicellular but with no tissue differentiation e.g amoeba, algae, slime moulds

13

Fungi

Eukaryotes with chitin cell walls, heterotrophic, reproduce using spores

14

Plantae

Autotrophic, multicellular eukaryotes with cellulose cell walls, photosynthetic (e.g chloroplasts contain chlorophyll)

15

Animalia

Heterotrophic, multicellular eukaryotes with no cell walls, nervous coordination

16

Autotrophic

Take simple inorganic molecules and convert into complex organic molecules to use as an energy source

17

Heterotrophic

Require ready made complex organic molecules to use as food/energy source

18

Homologous structures

Similar arrangement of component parts and similar developmental structure but different functions
(Same basic structure, different function)
Shows existence of common ancestry

19

Analogous structures

Corresponding function but different developmental origin
(Same function, different structure)
Shows no evidence for common ancestor

20

Convergent evolution

Unrelated species evolve similar features to overcome similar problems

21

DNA base sequences

Evolution, DNA base sequence changes in species, considered a different species, closely related species have similar DNA base sequences

22

DNA hybridisation

DNA extracted and cut into fragments
Fragments from 2 species mixed, where there are complimentary base pairs they hybridise together

Heat to 95 (hydrogen bonds break)
Combine strands
Cool down and hybrid DNA forms
Heat up, will break at less than 95 as fewer hydrogen bonds to break (DNA strands won't have identical base sequences)

23

Amino acid sequence

Determined by DNA base sequence
Similarity of proteins shows how closely related they are
Can produce evolutionary tree

Count amount of amino acid sequences in common, most in common=most closely related so have most common ancestor

24

Immunology

Antigens of one species mix with antibodies of another forming a precipitate
More they react, more precipitate made, more closely related

25

Species definition (reproductive definition)

Organisms are in same species if they can interbreed and produce fertile offspring

26

Taxonomy definition and what it allows

Identification & naming of organism allows description and discovery of biodiversity, investigate evolutionary relationships and classifications to reflect them

27

Why is binomial system used?

Latin = universal language
2 names= Genus species [must be underlined] (name is unique and specific)

28

Biodiversity

Number of species and number of individuals of each species in a given area

29

Simpsons index of biodiversity

S = 1 - sigma n(n-1) divided by N(N-1)

n = number of individuals
N = number of organisms sampled

30

'Gene pool'

All genes and alleles present in a population