4.2.2 classification and evolution Flashcards
order of classification
4.2.2(a)
Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species
what is the Genus and Species in homosapians
4.2.2(b)
genus-Homo
Species-sapiens
all should be underlined and genus should be capital
why is using a latin binomial name better than common name
4.2.2(b)
-universally accepted
-specifies genus of organism
what is comparative biochemistry
4.2.2(c)
evidence from biological molecules can help determine how closely related one species is to another
-two organisms with similar molecules have a more recent common ansetor as they have not evolved separately for long
-two organisms with very different versions of the molecule have a less recent common ansestor as they have evolved separately for longer
what are some molecules that are commonly compared
4.2.2(c)
-ribosomal RNA base sequence
-Haemaglobin primary structure sequence
-cytochrome C protein primary structure
how can a base sequence of a gene for a certain protein be compared
4.2.2(c)
the base sequence of a gene for a certain protein can be compared
-base sequence is similar=closely related
-more differences=less closely related
what is the 3 domain system based on
4.2.2(c)
there are many fundamental differences between bacteria and eukaryotes but also between bacteria and archaea
what are 4 differences between bacteria and archaea
4.2.2(c)
-different cell membrane structure
-different flagella structure
-different versions of RNA polymerase
-different mechanisms for DNA replication
what are 3 differences between bacteria and eukaryotes
4.2.2(C)
-Eukaryotes have
-nucleus
-MBOs
-80S ribosomes
what are some similarities between eukaryotes and archaea
4.2.2(c)
-similar RNA polymerase primary structure
-Similar mechanisms for DNA replication and transcription
-both contain histones
what is phylogeny
4.2.2(d)
study of evolutionary relationships between species using comparative biochemistry
how can you determine how closely related 2 organisms are
4.2.2(d)
the more recent there common ancestor is the more closely related they are
how are evolutionary relationships dictated
4.2.2(d)
by a phylogenetic tree
how did Wallace contribute to Darwin’s theory of evolution by natural selection
4.2.2(e)
-collected similar results which showed results are reproducible
-he arrived at the conclusion independently
-published paper together
what is comparative anatomy
4.2.2(e)
study of similarities and differences in the anatomy of different living species
what is a homologous structure
4.2.2(e)
Structure that appears to be different but has the same underlying structure
Eg-bat arm and human arm
what does the homologous structure provide evidence for
4.2.2(e)
divergent evolution- how species have evolved from common ancestors
what is comparative biochemistry
4.2.2(e)
making comparisons between cytochrome C and Ribosomal RNA this means they have a similar amino acid base sequence so a more similar primary structure so are more closely related or have a more similar base sequence
what is observable evolution
4.2.2(e)
we can observe evolution in organisms that evolve rapidly
what are the 2 pieces of evidence for evolution
4.2.2(e)
-fossils-shows similarities between extinct and current species
However we have an incomplete fossil record
More similar=more closely related
-molecular evidence-DNA
what is intraspecific variation
4.2.2(f)
variation within the same species
what is interspecific variation
4.2.2(e)
variation between different species
what is some ways genetic variation can occur
4.2.2(e)
-crossing over during prophase 1 of meiosis
-independent assortment of homologous chromosomes during metaphase 1 of meiosis
-independent assortment of chromatids during metaphase 2 of meiosis
-random fertilisations
-mutations
what are some environmental factors that can influence variation
4.2.2(e)
-light intensity-can influence plant height
-food availability-adult height
what is discontinuous variation
4.2.2(e)
using controlled by 1 gene loci
not affected by the environment
how is discontinuous variation shown
4.2.2(e)
bar chart
what is continuous variation
4.2.2(e)
shows a normal distribution
usually influence by more than 1 gene (polygeneic)
is influenced by the environment
how is continuous variation represented
4.2.2(e)
histogram
what should you plot on the y-axis in a histogram
4.2.2(e)
frequency density
how do you work out frequency density
4.2.2(e)
frequency / relative class width
what is an adaptation
4.2.2(g)
characteristic that enhances survival and reproductive success
what is an anatomical adaptation
4.2.2(g)
anatomical adaptation are structural features that increase an organisms fitness
what is a behavioural adaptation
4.2.2(g)
behaviours that aid an organisms survival in its environment
what is a physiological adaptation
4.2.2(g)
a process that takes place inside an organism that increases its fitness
what are analogous structures
4.2.2(g)
structures that have adapted to form the same function but have a different genetic origin
how do analogous structures arise
4.2.2(g)
analogous structure arise through convergent evolution when unrelated species share similar traits these evolve because organisms adapt to similar niches/selection pressures
what is an example of convergent evolution
4.2.2(g)
marsupials and placental mammals both have a strong resemblance in overall shape, type of locomotion and feeding techniques as they have adapted to similar climates/ food supplies
what are similar analogous structures that have developed though convergent evolution
4.2.2(g)
marsupial and placental moles both have
-cylindrical bodies
-small reduces eyes
-short fur and tail
-nose with tough skin for protection
explain the natural selection mechanism
4.2.2(h)
- mutations give rise to new alleles
2.the creates genetic variation - selection pressures favour alleles with the advantagous phenotype as they as they have a higher fitness so are more likely to survive and reproduce
- the beneficial alleles are passed onto offspring so the next generation will have a higher proportion of the advantagous allele and delirious alleles will die
explain pesticide resistance in insects
4.2.2(i)
pests can cause damage to food crops so insecticides are used to kill them. However the use of insecticides is a selection pressure. The insects will the allele for resistance are more likely to survive and reproduce so there frequency in the population will increase.
what are some problems concerned with insecticide resistance in insects
4.2.2(i)
insecticides build up in the food chain
explain antibiotic resistance in bacteria
4.2.2(i)
same as insects
give an example of a bug which is resistant to antibiotics
4.2.2(i)
MRSA
