classification and evolution

Question 1

what is classification

Answer 1

the name given to the process by which living organisms are sorted into groups, the organisms within each group share similar features

Question 2

what are the taxonomic levels

Answer 2

(domain) kingdom, phylum, class, order, family, genus, species

Question 3

what does the change in the classification system show us about science

Answer 3

that our scientific knowledge and understanding has developed over time, gathering new information

Question 4

why do scientists classify organisms

Answer 4

to identify species, to predict characteristics, to find evolutionary links

Question 5

how do you create a species binomial name

Answer 5

genus (capital letter) and species (lower case letter)

Question 6

what are the three domains

Answer 6

archaea, bacteria and eukarya

Question 7

what is a species

Answer 7

a group of organisms that are able to reproduce to make fertile offspring

Question 8

what are the five kingdoms

Answer 8

prokaryote, protoctista, fungi, plantae, animalia

Question 9

Animalia

Answer 9

multicellular, has a nucleus, all organelles except chloroplasts, no cell wall, nutrients are acquired by ingestion (heterotrophic feeders), food is stored as glycogen, cilia, flagella, contractile proteins e.g lizards

Question 10

Plantae

Answer 10

multicellular, nucleus, all contain chlorophyll, cell wall mainly composed of cellulose, nutrients acquired by photosynthesis (autotrophic feeders), make their own food and store it as starch, most don’t move but gametes of some plants move using cilia or flagella, e.g roses

Question 11

Fungi

Answer 11

unicellular or multicellular, nucleus, no chloroplasts or chlorophyll, cell wall mainly composed of chitin, acquired by absorption mainly from decaying material (saprophytic feeders) some are parasitic, store their food as glycogen, no mechanisms for locomotion, Yeasts

Question 12

prokaryote

Answer 12

unicellular, no nucleus or other membrane-bound organelles, ring of ‘naked’ DNA, small ribosomes only, cell wall flexible and made of peptidoglycan, no visible feeding mechanism, nutrients absorbed through cell wall or produced internally through photosynthesis, flagellum (some) E.g staphylococcus aureus

Question 13

Protoctista

Answer 13

mainly unicellular, nucleus, some have chloroplasts and membrane bound organelles, some have cell walls, nutrients acquired by photosynthesis and ingestion of other organisms (autotrophic and heterotrophic feeders), some are sessile, others move by cilia or flagella e.g Amoeba Paramecium

Question 14

Eukarya

Answer 14

have 80s ribosomes, RNA polymerase contains 12 proteins

Question 15

Archaea

Answer 15

have 70s ribosomes, RNA polymerase contains between 8 and 10 proteins

Question 16

Bacteria

Answer 16

have 70s ribosomes, RNA polymerase contains 5 proteins

Question 17

what are archaebacteria and eubacteria

Answer 17

come from when the prokaryote kingdom divides in two

Question 18

what is the difference between eubacteria and archaebacteria

Answer 18

eubacteria contain peptidoglycan in their cell walls whereas archaebacteria do not

Question 19

what is phylogeny

Answer 19

the name given to the evolutionary relationships between organisms

Question 20

what are the advantages of phylogenetic classification

Answer 20

can be done without reference to Linnaean classification, produces a continuous tree, Linnaean classification can be misleading

Question 21

how does evolution work

Answer 21

organisms best adapted to their environment are most likely to survive and reproduce, passing on their characteristics to their offspring

Question 22

what is the evidence for evolution

Answer 22

palaeontology, comparative anatomy, comparative biochemistry (chemical makeup)

Question 23

where are the oldest fossils found

Answer 23

deeper down in the rock

Question 24

what evidence is provided by the fossil record

Answer 24

bacteria found in oldest rocks whilst vertebrated are found in more recent rocks, plant fossils appear before animal fossils, links organisms to their common ancestors, allow relationships between extinct and living organisms to be investigated

Question 25

what are the disadvantages of fossils

Answer 25

soft bodied organisms decompose quickly before they can fossilise, conditions not always right for fossils to form, or fossils destroyed by the Earth's movements

Question 26

what is a homologous structure

Answer 26

a structure that appears superficially different ( and may perform different functions) in different organisms, but has the same underlying structure. E.g pentadactyl limb of vertebrates

Question 27

what is divergent evolution

Answer 27

how, from a common ancestor, different species have evolved, each with a different set of adaptive features, occurs when closely related species diversify to adapt to new habitats as a result of migration or loss of habitat

Question 28

what is comparative biochemistry

Answer 28

the study of similarities and differences in the proteins and other molecules that control life processes

Question 29

how do scientists decide how closely two species are related

Answer 29

the molecular sequence of a particular molecule is compared, order of DNA bases or order of amino acids in a protein.

Question 30

why is ribosomal DNA used to compare species

Answer 30

slow rate of substitution

Question 31

what is intraspecific variation

Answer 31

variation between members of the same species

Question 32

what is interspecific variation

Answer 32

variation between organisms or different species

Question 33

what are the two causes of variation

Answer 33

genetics and environment

Question 34

what are the causes of genetic variation

Answer 34

Alleles, Mutations, Meiosis, Sexual reproduction, chance

Question 35

what is an example of a characteristic that is determined purely by genetic variation

Answer 35

your blood group

Question 36

why are plants affected by environmental factors more than animals

Answer 36

lack of mobility

Question 37

what is an example of a variation that is purely determined by your environment

Answer 37

scars

Question 38

what is discontinuous variation

Answer 38

a characteristic that can only result in certain values, no in between values, e.g blood groups, mostly genetic

Question 39

what is continuous variation

Answer 39

a characteristic that can take any value within a range e.g height and mass of a plant. Environmental factors can have an influence.

Question 40

what is standard deviation a measure of

Answer 40

how spread out the data is

Question 41

what is a student's t test used to measure

Answer 41

compare the means of data values of two populations

Question 42

what is Spearman's rank correlation coefficient used to measure

Answer 42

to consider the relationship between two data sets

Question 43

what are the three types of adaptations

Answer 43

behavioural, anatomical, physiological

Question 44

what are some examples of anatomical adaptations

Answer 44

body covering, camouflage, teeth, mimicry

Question 45

what are the adaptations of marram grass

Answer 45

curled leaves to minimise surface area of moist tissue exposed to air, and protect leaves from wind hairs on the inside surface of the leaves to trap moist air to the leaf stomata sunk into pits, which make them less likely to open and lose water A thick waxy cuticle on the leaves and stems reducing evaporation

Question 46

what are some examples of behavioural adaptations

Answer 46

survival behaviours courtship seasonal behaviours e.g migration and hibernation

Question 47

what are the categories of behavioural adaptions

Answer 47

innate and learned behaviour

Question 48

what are some examples of physiological adaptations

Answer 48

poison production, antibiotic production, water holding

Question 49

what are analogous adaptations

Answer 49

structures that have adapted to perform the same function but have a different genetic origin

Question 50

what is convergent evolution

Answer 50

when unrelated species start to show the same traits

Question 51

why does convergent evolution occur

Answer 51

because species adapt to fill similar niches

Question 52

what are some examples of convergent evolution

Answer 52

marsupial and placental mice, flying phalangers and flying squirrels, marsupial and placental moles, aloe and agave

Question 53

what are selection pressures

Answer 53

factors that affect the organism's chances of survival or reproductive success

Question 54

what are the steps of natural selection

Answer 54

genetic variation occurs within a species which is caused by differences in genes and mutations, organisms who are best selected to selection pressures have an increased chance of survival and reproduction (survival of the fittest), the successful organisms pass on the advantageous characteristic onto their offspring , process is repeated for every generation and over time leads to the evolution of a new species

Question 55

what are some modern examples of evolution

Answer 55

MRSA, Peppered moths, sheep blowflies, flavobacterium

Question 56

what is the founder effect

Answer 56

when few individuals of a species colonise a new area, their offspring initially experience a loss in genetic variation, often resulting in individuals that are physically and genetically different from their source population.

Question 57

what is specification

Answer 57

the evolution of a new species