Classification and Evolution Flashcards

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1
Q

define species

A

group of similar organisms capable of producing fertile and living offspring

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2
Q

Darwins theory of evolution is based on what observations

A

variation exists between members of the same species
these variations are inherited from parents
organisms tend to overproduce
populations remain stable

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3
Q

from darwins observations, what did he conclude

A

survival is a struggle
those with more advantageous characteristics survive to pass them onto their offspring
over many generations small changes can lead to changes and speciation

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4
Q

the modern theory of evolution is called

A

Neo-Darwinism

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5
Q

causes of variation in a phenotype

A

environmental and genetic factors

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6
Q

what are the causes of genetic variation

A

mutations- primary source
meiosis
random fertilisation of gametes

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7
Q

how do mutations cause genetic variation

A

changes to genes and chromosomes may or may not be passed onto next generation

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8
Q

causes of mutations

A

mutagenic agents such as ionising radiation and tobacco smoke

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9
Q

how does meiosis cause genetic variation

A

produces new combination of alleles before they are passed onto the gametes therefore they are all different

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10
Q

how does random fertilisation of gametes cause genertic variation

A

produces new combinations of allels and offspring are therefore different to parents

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11
Q

give examples of continuous variation

A

height, mass

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12
Q

give examples of discontinuous variation

A

blood type, eye colour, hair colour

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13
Q

what does a normal distribution curve look like

A

a bell shaped curve

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14
Q

environmental influences on genetic variation include:

A

climatic conditions eg temp, rainfall, sunlight
soil conditions
pH
food availability
diet is an environmental impact that can affect height

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15
Q

individuals genetically predetermined to be the same can height grow to different heights. This typeof variation is produced by?

A

polygenes and the environment

diet can affect height

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16
Q

continuous variation vs discontinuous variation (4)

A
continuous: 
shows a full range of intermediate values between 2 extremes 
determined by many genes- polygenic
strong environmental influence 
often a normal distribution curve on a histogram 
discontinuous:
data flows into discrete categories
determined by a flow of genes 
weak environmental influence 
bar chart
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17
Q

define selection pressures

A

environmental factors that limit the population of a species
includespredation, disease, competition

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18
Q

effect of selection pressures

A

determine the frequency of alleles within the gene pool

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19
Q

define gene pool

A

total number of all the alleles of all the genes of all individuals with a population at a given time

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20
Q

define fitness

A

the ability of an organism to pass on its alleles to subsequent generations, compared with other individuals of the same species- the fittest individual produces the largest number of organisms that reproduce themselves

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21
Q

what are the 3 types of adaptions

A

anatomical, physiological and behavioural

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22
Q

define anatomical adaption

A

a mutation that has caused the physical features of an organism to change eg increased fur

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23
Q

define physiological adaption

A

a mutation that has changed the biochemistry of that organism eg the ability to oxidise fat instead of carbohydrates

24
Q

define behavioural adaption

A

a learned adaption where the organism has learnt a behaviour that is differnet to their normal routine eg migrating to a diff country in the winter

25
Q

what does MAVAIPS stand for

A

mutation, allele, variation, advantage/adaption, inheritance, population, speciation

26
Q

three types of natural selection

A

stabilising selection, directional selection, disruptive selection

27
Q

characteristics of a stabilising selection

A

def: favours average individuals so preserves characteristics of the population
an unchanging environment.
the extremes of a phenotype are not favourable and therefore there is a reduction in variation
the bell shaped curve gets pushed narrower from both sides

28
Q

characteristics of a directional selection

A

def: favours one extreme of the phenotype rnage and results in a shif of the mean to the right or left
this selection usually follows an environmental change

29
Q

characteristics of a disruptive selection

A

def; selects against intermediate phenotypes and favours those at the extremes
leads to bimodal distribution (2 peaks)

30
Q

disruptive selection leads to overalp between 2 groups of phenotype. how would new species be created

A

if the 2 groups become unable to interbreed, then each population may give rise to a new species

31
Q

how can new species be formed

A

when 2 populations of a species are split into diff environments, the reproductive isolation leads to new species

32
Q

outline the evolution of antibiotic resistance

A

bacteria tolerate levels of antibiotic that would normally inhibit growth

33
Q

describe 2 ways in which antibiotic resistance can become widespread

A

1- transfer of genetic material between bacteria

2- increased resistance with each generation due to natural selection

34
Q

how can a population of resistant bacteria develop

A

if the amount of antibiotic delivered is too low or the course of antibiotics is not completed

35
Q

define classification

A

organisation of living organsims into groups

36
Q

what does fertile mean

A

if 2 different species breed,one can have an even number of chromsomes, one can have an odd number of chromsomes therfore the diploid number is odd- this leaves a singular chromosome and therefore offspring is infertile

37
Q

effect of uneven diploid number on meiosis

A

uneven diploid number means that meiosis cant occure and so fertile offspring are not produced

38
Q

binomial system features

A

universal system based upon Latina nd greek names
the generic names relates to the genus
the specific name relates to the species

39
Q

rules of binomial system

A

names initalics or underlined if handwritten
first letter of the generic name is upper case
if species name is unknown it can be written as sp

40
Q

do members of the same species have similar genes?

A

yes- similar or same

41
Q

courtship behaviour helps to achieve the max chance of survival by enabling individuals to:

A

1-recognise members of their own species
2-identify a mate that is capable of breeding- both need to be sexually mature, fertile
3-synchronise mating- takes place when there is a max probability of sperm and egg meeting
4-become able to breed-by bringing a member of the opposite sex into a physiological state that allows breeding to occur

42
Q

features of phylogenetic classification

A

based upon the evolutionary relationships between organisms and their ancestors
classifies species into groups using hared features derived from their ancestors
arranges the groups intoa hierarchy with no overlap

43
Q

what is a taxon

A

each group within a phylogenetic biological classification

44
Q

what are the names of the taxons

A

Domain, Phylum, Class, Order, Family, Genus, Species

45
Q

what are the domains in a phylogenetic classification

A

bacteria, archae and eukarya

46
Q

what are archaea

A

groups of single celled prokaryotes

47
Q

how do archaea differ from bacteria

A

their genes and protein synthesis is more similar to eukaryotes
membranes contain fatty acid chains and attached to glycerol by ether linkages
no murein in their cell walls
have a more complex form of RNA polymerase

48
Q

define phylogeny

A

evolutionary relationship between organisms

49
Q

define hierarchy

A

large groups split into smaller groups which do not overlap

50
Q

how does a phylogenetic system differ from a simple hierarchy

A

phylogenetic is based on evolutionary history
shows ancestory of groups
hierarchal based on shared characteristics

51
Q

limitations of comparing visible characteristics to compare genetic diversity

A

some visual characteristics are coded for by more than one gene so its difficult to distinguish one change from another
some visual characterists may be controlled from the environment and may not have anything to do with a change in the alleles

52
Q

how is comparison of DNA base sequences carried out

A

DNA extracted from individuals and the nucleotide bases each tagged a diff colour- computer reads the diff colours and shows the order of nucleotides
coding DNA is used as these sequences will be very similar within a species

53
Q

ways of comparing genetic diversity

A

compare the base sequence of DNA
compare the base sequence of mRNA
compare the sequence of amino acids in proteins

54
Q

explain the principles which biologists use to classisfy organisms into groups

A

large groups are divided inot smaller groups
members of a group have features in common basedon anatomy/ DNA/ homologous structures
reflects evolutionary history

55
Q

differences in haemoglobins primary structure can provide evidence of phylogenetic relationships between species. Explain how (5)

A

mutations change base/nucleotide sequence
causes change in AA sequence
mutations build up over time
more mutations/ differences between distantly related species
closely related species have recent common ancestor