chapter 10 - classification and evolution Flashcards
what is classification
the name given to the process by which living organisms are sorted into groups
what are the 7 taxonomic groups
kingdom
phylum
class
order
family
genus
species
why do scientists classify organisms
to identify species
to predict characteristics
to find evolutionary links
what are the 3 domains when seperating organisms
arachea, bacteria and eukarya
what are species
a group of organisms that are able to reproduce to produce fertile offspring
why are miles and hinnies infertile
their parents are different species therefore they have an odd number of chromosomes so meiosis and gamete production cant take place
what is binomial nomenclature
the first word in species name indicate genus
second name indicates species
what are the 5 kingdoms
prokaryotae - bacteria
protoctista - unicellular eukaryotes
fungi - yeasts, moulds
plantae - plants
animalia- animal
what are the features of prokaryotae
unicellular
no nucleus or membrane bound organelles
small ribosomes
no visible feeding mechanism ( nutrients absorbed through cell wall or produced internally by photosynthesis)
what are the features of protoctista
mainly unicellular
has nucleus and membrane bound organelles
some have chloroplasts
some are sessile but others move by cilia
nutrients acquired by photosynthesis , or ingestion of other organisms or both ( parasites)
what are autotrophic organisms
nutrients acquired by photosynthesis
what are heterotrophic organisms
ingestion of other organisms
what are features of fungi
unicellular or multicellular
has nucleus and membrane bound organelles and a cell wall made of chitin
no chloroplasts or chlorophyll
no mechanisms for locomotion
body made of mycellium made of hyphae
gain nutrients by absorbing decaying material
store food as glycogen
what are saprophytic feeders
absorb nutrients from decaying material
what are features of plantae
multicellular
has nucleus and membrane bound organelles
has chloroplasts and chlorophyll
has cell wall made of cellulose
do not move but gametes move by cilia
autotrophic
store food as starch
what are features of animalia
multicellular
has nucleus and membrane-bound organelles
no cell wall
no chloroplasts
move with aid of cilia , flagella or contractile proteins
heterotrophic
store food as glycogen
what are the differences in 3 domains
sequence of nucleotides in rRNA , cell membrane lipid structure and sensitivity to antibiotics
what are the features of eukarya
80S ribosomes
RNA polymerase contains 12 proteins
what are the features of archaea
70S ribosomes
RNA polymerase contains between 8 and 10 proteins
what are the features of bacteria
70S ribosomes
RNA polymerase contains 5 proteins
what 2 kingdoms does the prokarotae kingdom split 2
archaebacteria
eubacteria
what is the difference between archaebacteria and eubacteria
archaebacteria has different chemical makeup
e.g eubacteria has cell wall made of peptidoglycan whereas archaebacteria does not
what is archaebacteria
live in extreme conditions such as acidic, anaerobic
what are methanogens
archaebacteria that live in anaerobic conditions such as sewage treatment plants and make methane
what is eubacteria
found in all environments
what is phylogeny
name given to the evolutionary relationship between organisms
what are the advantages of phylogenetic classification
can be done with reference to Linnaean classification
produces a continuous tree whereas classification required to discrete taxonomical groups
hierarchal nature of linnaean classification can be misleading as it implies different groups within same rank are equivalent
what are the evidence of evolution
paleontology - study of fossils and fossil record
comparitive anatomy - study of similarities and differences between organisms anatomy
comparitive biochemistry - similarities and differences between chemical makeup of organisms
what is the evidence provided by fossil record ( paleontology)
fossils of simplest organisms such as bacteria are found in oldest rocks therefore support evolutionary theory that simple life forms gradually to more complex ones
sequence in organisms are found matches ecological links for example plant fossils appear before animal fossils therefore showing animal need plants to survive
by studying similarities in anatomy of fossil organisms we can see how closely related organisms have evolved
fossils allow relationships between extinct and living organisms to be investigated
what are the disadvantages of fossil record
many organisms are soft bodies and decompose quickly before they have a chance to fossilise
what is homologous structure
structure that appears superficially different and may perform different functions in different organisms but has same underlying structure
what is divergent evolution
describes how different species have evolved from a common ancestor each with a different set of adaptive features
why does divergent evolution occur
when closely related species diversify to adapt to new habitats as a result of migration or loss of habitat
what is evolutionary embryology
shows how similar different animals develop so processes of embryonic development has common origin
what is intraspecific variation
differences between organisms within a species
what is interspecific variation
difference between different species
what factors cause variation
differences in genetic material an organism inherits from parents leads to genetic variation
environment in which organism lives - environmental variation
what causes genetic variation
different alleles
mutations
meiosis by independent assortment and crossing over
sexual reproduction
chance
what are the 3 types of adaptations
anatomical - physical features
behavioural - way organism acts
physiological - processes that take place inside organism
what are adaptations of marram grass ( xerophyte)
curled leaves
hairs on inside surface of leaves
sunket stomata
thick waxy cuticle
what are some anatomical adaptations
body covering
camouflage
teeth
mimicry
what are some behavioural adaptations
survival behaviours
courtship
seasonal behaviour
migration
hibernation
what are the 2 categories of behavioural adaptations
innate - inherited through genes
learned - learnt from experience or observing other animals
what are some physiological adaptations
poison production
antibiotic production
water holding
what is convergent evolution
when unrelated species share similar traits
what are analogous structure
when species have structures with same function but different genetic origin
what causes natural selection
selection pressures
