Evolution Flashcards
What is continuous variation?
It has no distinct categories, quantitative data and has no limit value
E.g. (height, weight)
Line graph
Controlled by gene and environment
What is discontinuous variation?
There are distinct categories, usually the data is qualitative
E.g (fingerprints, blood group, tongue rolling)
Bar graph
Controlled by a few genes
Define evolution
The gradual process of genetic change in a population that is inherited over several generations
How are fossils formed
Animals die near sedimentary rocks, dead organisms are buried by new layer of earth and rock, they are preserved in the buried rock layer as the calcium in the bones of the organism has mineralized so they harden.
What are the 2 categories of fossils
Trace fossil and body fossil
Body fossil or trace fossil? The remains of body parts
Body fossil
Give some examples of body and trace fossils
Body = shell, bone, teeth
Trace = footprints, faeces
What is a trace fossil?
Something an organism has left behind
True of false, the deeper the strata (laid down layers of sedimentary rock) the younger the organism is
False
What are the 2 methods to determine age of fossils
Relative dating and absolute dating
Which type of dating is this?, Look at another fossil either younger or older, but we don’t know the exact age
Relative dating
What is absolute dating
We can determine exact age of the fossil (via carbon dating)
What is carbon dating
Radioactive C-14 in the atmosphere turns into radioactive CO2 which plants use to photosynthesise and is incorporated into animals when the plants are eaten. We then measure the decay of the C-14 using its half life as guidelines for the age of the fossil
The older a sample, the less C-14 is detected, true or false
True
What are the 6 evidences of evolution
Fossils, geographical distribution, comparative anatomy, comparative embryology, biochemistry and DNA homology
What is geographical distribution
Closely related organisms are now geographically separated so adapt to new environments, due to natural selection and environmental pressures new species are gradually produced via adaptive radiation
What is homologous structure
A similar structure from different species that perform a different function. The organisms evolve from a common ancestor
What is convergent evolution
Organisms evolve by converging towards a shared function e.g. different structure but similar function
What is analogous structure
Organisms have no common ancestor but the structures are used for similar functions e.g. penguin and dolphin (fins/flippers)
What is divergent evolution
When organisms evolve by diverging away from the original species e.g. same structure different function
What is vestigial structure
Organisms have structures that are useless or have lost their original function e.g. appendix and wisdom teeth
What are the types of evolution
Divergent evolution, convergent evolution, vestigial evolution
What type of evolution is this , evolution out of a certain adaptation
Vestigial evolution
True or false, most vertebrate have different early embryonic development
False
True or false, embryos from different species only start to lose their similarities in the later stages of embryonic development
True
How is biochemistry used to compare organisms
Universal bases of nucleic acids, metabolic pathways of physiological processes (e.g. breathing, digestion) and the universal use of ATP energy