classification and evolution Flashcards
1
Q
who invented hierarchical classification?
A
carl linnaeus
2
Q
what is the taxonomic rank?
A
domain
kingdom
phylum
class
order
family
genus
species
3
Q
what are the three domains?
A
- eukarya
- eubacteria
- archaea
4
Q
what are the 5 kingdoms?
A
- plantae
- animalia
- protoctista
- fungi
- prokaryote
5
Q
what is a species?
A
group of individual orgaisms whose members are able to interbreed and produce viable, fertile offspring
6
Q
what are the advantages of binomial nomenclature?
A
- easier identification based on recognised characteristics
- predict characteristics
- evolutionary link
- globally recognised
7
Q
what is taxonomy?
A
classification of organisms based on observable characteristics
8
Q
what is phylogeny?
A
evolutionary relationships
9
Q
what is a hierarchy?
A
larger groups broke down into smaller ones
10
Q
who introduced domains?
A
carl woese
11
Q
why were domains introduced?
A
study of RNA polymerase, cell wall material and cell membrane structure showed that prokaryotes could be split into two groups
12
Q
what are the similarities between archaea and eukarya?
A
- lacks peptidoglycan in cell walls
- methionine is the start codon in protein synthesis
- growth not inhibited by streptomycin
- histones are associated with DNA
- several types of RNA polymerase
13
Q
what are similarities between archaea and eubacteria?
A
- circular chromosomes
- lacks nuclear envelope
- lacks membrane bound organelles
- 70s ribosomes
14
Q
what are the features of animalia?
A
- membrane bound organelles
- no cell wall
- nucleus
- heterotrophic
- muticellular
15
Q
what are the features of plantae?
A
- membrane bound organelles
- cell wall of cellulose
- nucleus
- autotrophic
- multicellular
16
Q
what are the features of fungi?
A
- membrane bound organelles
- cell wall of chitin
- nucleus
- heterotrophic/saprophytic
- multi or unicellular
17
Q
what are the features of prokaryotes
A
- no membrane bound organelles
- cell wall of peptidoglycan
- no nucleus
- unicellular
- hetero or autotrophic
18
Q
what are the features of protoctista?
A
- membrane bound organelles
- sometimes have a cell wall of various chemicals
- nucleus
- autotrophic or heterotrophic
- unicellular
19
Q
what is phylogenetic classification?
A
- grouped based on evolutionary links
- greater level of homology in amino acid sequences means they are expected to be closely related
20
Q
how is a scientists research validated?
A
- reproduced with the same results
- more supporting evidence
- peer review
21
Q
what is evolution?
A
gradual change in heritable traits of organisms over many years
22
Q
what were darwins 4 key observations?
A
- organisms produce more offspring than survive
- variation in characteristics of the same species
- these are passed on through generations
- best adapted to the environment survive
23
Q
what are the principles of natural selection?
A
- overproduction leads to competition
- variation due to mutation
- selection via adaption
- breed and pass on characteristic
24
Q
what are the causes of variation?
A
- enviromental factors
- meiosis (crossing over, independent assortment)
- mutations and alleles
25
intraspecific vs interspecific?
- intra is variation between individuals in a species
- inter is variation between members of different species
26
what are selection pressures?
external agents which affect an organisms ability to survive in a given environment
27
what are some examples of selection pressures?
- predators
- resources and nutrients
- disease
- abiotic factors (temp, pH)
28
why did people originally oppose Darwins theory of evolution?
- belief in God
- people didnt want to descend from apes
- no evidence as alleles hadnt been discovered
29
what is a pentadactyl limb and what are its different uses?
- mammals, reptiles birds etc all share a similar 5 digit limb
birds - flying
humans - tool handling
whales - swimming
30
what is the evidence for evolution?
- comparative anatomy
- embryology (embryo development)
- DNA (amino acid chains, base triplet codes, similar alleles)
- fossil records (remains preserved in rocks, can identify ancestors)
31
what are homologous structures?
similar anatomical structure but different superficial structure
32
what are analogous structures?
similar superficial structure but different anatomical structure
33
what are homologous and analogous structures evidence for and how do they occur?
homologous - divergent evolution
- due to common ancestors
analogous - convergent evolution
- due to common selection pressures
34
convergent evolution case study
marsupial and placental moles
- no eyes as they dont need to see undergroud
- n external ears to make head streamlined for burrowing
- claw suitable for digging
35
what is intraspecific variation?
differences between populations of the same species
36
what is interspecific variation?
differences between different species
37
how are scientists able to estimate the age of extinct organisms?
fossils that are further in the ground are older than ones closer to the top
38
why is the 3 domain system used instead of the 5 kingdom system?
- better reflects evolutionary relationships
- key differences between bacteria and eukaryotes
- differences between bacteria and archaea eg dna replication methods
39
explain how phylogeny is related to classification
- phylogeny is study of evolutionary relationships and is the basis for evolution
- species with common ancestors and similar evolutionary history are classified together
40
how is a specific molecule used to determine how species have evolved from common ancestors?
- sequences of amino acids
- the smaller the percentage difference between sequences the more closely related they are
41
why can scottish wildcat and english wildcat not yet be different species?
- can still produce fertile offspring
- still genetically similar
42
how do biological molecules provide evidence that species have evolved?
- if DNA base sequences in both species show similarity then they have close recent common ancestors
- if amino acid sequences in proteins are similar it implies evolutionary relations
43
describe types of evidence that support evolution
similarities in:
- amino acid sequences
- DNA base sequencing
- RNA polymerase
more similar means more closely related
- comparison of behaviours eg. similar finches occupying different niches
- comparision of anatomy eg pentadactyl limb
44
what are the conditions for speciation to occur?
- isolation
- allele mutation
- different selection pressure
- natural selection
45
why would small isolated groups of the same species in different regions become extinct faster?
- limited gene pool so cannot adapt to environmental changes
- all wiped out by one disease
- more vulnerable to predators
46
