B15: Genetics and Evolution Flashcards
who was the man who helped discover inheritance
Mendel
what was mendel’s work
he carried out breeding experiments on peas, discovering the patterns within genes.
who were the two teams that helped discover DNA in the 1950’s
Watson and Crick
Wilkins and Franklin
what is gene theory
genes code for proteins and this is how they have their affect
who’s theory was evolution
darwin
who was the first man to theorise evolution
Lamarck
what was Lamarck’s theory
the ‘fountain of life’. every animal evolved from primitive worms. features were kept if used.
what was the animal Darwin primarily studied
finches
Darwin believed in what…? (theory)
natural selection
survival of the fittest etc.
who was developing similar ideas to Darwin later on?
Wallace
why did people object to the origin of species
-Christian, God made Earth
-Not enough evidence
-No way to explain how it happened.
what idea did Wallace contribute to (not evolution)
speciation
when is it a new species
when they can no longer interbreed to produce fertile offspring
process of speciation
-population becomes isolated
-alleles best for new conditions change
-new genetic variation, or ‘fittest’.
two types of isolation (species being separated.
-geographical (physical boundary)
-environmental (habitat changes)
what destroyed the dinosaurs? how do we know?
asteroid, crater in Mexico with iridium (rock formed when asteroid hits)
how do resistant bacteria develop
-antibiotic used
-resistant live, reproduce and multiply
-new population of bacteria resistant to antibiotic
how to prevent resistant strains of bacteria
-antibiotics only used to treat serious bacterial infections.
-patients finish the course of medicine, so no bacteria survive and mutate
-restricting agricultural use.
-doubling up on antibiotics, more chance of killing all.
MRSA outbreak
in hospitals, resistant to antibiotics, deaths were so many
what is the order of classification
domain, kingdom, phylum, class, order, family, genus and species
(DKPCOFGS)
what are the 3 domains?
archaea (primitive bacteria)
bacteria
eukaryotes
6 kingdoms:
-archaebacteria
-eubacteria
-protista, fungi, plants, animal
what kind of model can we look at to find common ancestors between species
evolutionary tree
what are fossils
the remains of organisms from millions of years ago, found in rocks, ice, and other places
3 ways fossils are formed:
-absence of decay
-parts replaced by minerals as they decay
-preserved traces of organisms
more about fossils due to absence of decay
not the correct conditions, e.g. little oxygen, poisonous gas, low temp.
rare but very informative, can even extract DNA
more about fossil parts minerals (yk)
carcass forms a mould in the mud and then decays, mould gets filled in.
examples of fossilised traces
footprints, droppings
how is a fossil formed
dies, buried in layers, long time, emerge when rocks move
how can extinction happen
-change in temperature
-new predators
-new diseases
-more successful competitors
-single catastrophic events
