4.3 classification and evolution Flashcards
why do we classify living things
convenience
make study of living things more manageable
easier to identify organisms
help us see relationships between species
define classification
process of placing living things into groups
what are the 8 taxonomic levels of classification
domain
kindgom
phylum
class
order
family
genus
species
what are the three domains
archaea
bacteria
eukaryotae
what are the 5 kingdoms
plantae
animalia
fungi
protoctista
prokaryota
what is the species level
the basic level of classification
what is the binomial naming system
system that uses the genus name and the species name to name and prevent confusion
define species
group of organisms that can successfully interbred to produce fertile offspring
what is the phylogenic definition of a species
group of individual organisms that are very similar in appearance, anatomy, physiology, and genetics
describe features of the prokaryotae kingdom
no membrane bound organelles
free living or parasitic
Unicellular
heterotrophic
autotrophic
describe features of the protoctista kingdom
are eukaryotic
membrane bound organisms
mostly free living
heterotrophic
cell wall sometimes present
describe features of the fungi kingdom
are eukaryotic
walls made of chitin
mostly free living or saprophytic (causes decay)
heterotrophic
describe features of the plantae kingdom
are eukaryotic
are multicellular
cellulose cell wall
autotrophic
membrane bound organelles
decribe features of the animalia kingdom
are eukaryotic
multicellular
heterotrophic
can move around
define heterotrophic
cannot produce its own food/ relies on an organism
define autotrophic
build larger molecules/ get its own food
evidence for classification/ natural selection
comparative biochemistry
comparative anatomy
paleontology
describe how paleontology provides evidence
shows preserved dead plants/ animals
shows how species were different using fossil record
why is the fossil record incomplete
fossils destroyed
organisms decompose or are soft bodied
conditions for fossils are not present
describe how comparative anatomy provides evidence
organisms with homologous strucutres
can study the similarities and differences between organisms anatomy
what is homologous structure
same underlying structure even though they might appear different and have different function
describe how comparative biochemistry provides evidence
studying similarities and differences in proteins and other biological organisms
helps identify evolutionary relationships
what is cytochrome c
protein used in respiration
how can cytochrome c be used for evidence in classification
all respiring living organisms contain it
but it is not identical
amino acid chain can be identified and conclusions can be drawn about how closely related species are
what conclusions can be made from the amino acid chain in cytochrome c in different species
sequences same = closely related
bigger difference = less closely related
define phylogeny
the study of evolutionary relationships between organisms
what are the two types of classification
artificial
natural
describe artificial classification
grouping organisms based on a few characteristics
does not reflect any evolutionary relationships, provides limited information, is stable
describe natural classification
grouping organisms using many characteristics
reflects evolutionary relationships, provides lots of useful information but may change with advancing knowledge
what does common ancestor mean in relation of species
more recent the common ancestor the more closely related two species are
how does phylogeny use the ‘common ancestor’
on the phylogenic tree we can see how recently the common ancestor appears to see how closely related species are
what is natural selection
individual that has advantageous characteristic which can help it to survive and reproduce
who was involved in the theory of evolution and natural selection
Darwin
Wallace
what were darwins observations
offspring appear similar to their parents
no two individuals are identical
organisms have the ability to produce large numbers of offspring
populations tend to remain fairly stable in size
how does natural selection take place
mutation creates alternative version of a gene (allele)
creates genetic variation between individuals in species (intraspecific variation)
individuals with advantagous characteristic get selected by the envi. (selection pressure)
survive and reproduce
passes on the characteristics
becomes more common in the species = adaption
what is a gene pool
combination of all the genes present in a species
what is an allele
version of a gene
what does phenotype mean
observable characteristics
what does genotype mean
genetic make up of an organism
define continuous variation
variation where there are two extremes and a full range of values inbetween
define discontinuous variation
where there are distinct categories and nothing inbetween
define environmental variation
variation caused by response to environmental factors
define genetic variation
variation caused by possessing a different combination of alleles
define interspecific variation
The difference between species
define intraspecific variation
variation between members of the same species
define variation
the presence of variety/ difference between individuals
what are the causes of variation
genetic
environment
gives examples of continuous variation in organisms
height
weight
leaf length etc
gives examples of discontinuous variation in organisms
tounge rolling
finger prints
blood group etc
what is continuous variation controlled by
gene and environment
what is discontinuous variation controlled by
genes
what is evolution
gradual process by which the diversity of living organisms have developed over millions of years
explain the difference between a pesticide and insecticide
chemicals designed to kill pests
specifically targets insects
explain why pesticide resistance is dangerous to humans
insects with resistance to will survive and reroduce passing on charactistics
resistance spreads
causes pesticide to become present/ accumulate in food chain
explain the MRSA super bug
bacteria that has a wide range of resistance to drugspopulation is becoming rapidly resistant
explain how microorgansims become resistant
genetic variation caused by mutations
least reisistant get killed
population of resistant reproduce
next generation contain higher proportion of resistant individuals
define adaption
a characteristic that enhances survival in the habitat
what can a well adapted organism do
find food/water or photosynthesis well
gather enough nutrients
defend itself
survive its environment conditions
respond to changes in environment
have sufficient energy to allow reproduction
name the three types of adaptions
anatomical
behavioral
physiological
what is anatomical adaption
anatomy/ structural features
what is behavioral adaption
the way an organism behaves in order to survive
what is physiological adaption
the processes/biochemistry inside organisms
what is convergent evolution
process where organisms not closely related evolve similar characteristics as a result of adaption to similar environments
Why do we use statistical tests
To determine whether a difference between two figures may or may not be significant
What is standard deviation
A measure of the spread around a mean
Explain what a low and high standard deviation means
Low SD = indicates data have a narrow range and points are close to the mean = greater reliability
High SD = data points have a larger ranges and are less well grouped = lower reliability
What is the students t - test
Used to compare two means and whether the difference is significant and if we can reject of accept the null hypothesis
What is the spearman’s rank correlation coefficient
Used to consider the relationships between two sets of data and whether they are correlated or not
