Chapter 14 Questions Flashcards
what is adaptation?
an inherited characteristic that improves an organism’s ability to survive and reproduce in a particular environment
what ship did Charles Darwin sail around the work on in the 1830s?
the Beagle
What did Darwin’s observations lead him to suggest?
that species change as they adapt to their changing environment
what is evolution
all of the changes that have transformed life over an immense time
what is Darwin’s theory of evolution two main points?
decent with modification and natural selection
what are the types of evidence for evolution?
fossils and the geographic distribution of modern species. the structures, embryos, and DNA of modern species also provide evidence
where are most fossils found?
in sedimentary rock layers
how can you tell if species recently shared a common ancestor?
the more similar the DNA sequences, the more recently the species shared a common ancestor
what observations did Darwin base his theory of natural selection on?
1) species tend to produce more individuals than the environment can support.
2) there is much variation among members of the same species
what individuals leave the most offspring?
individuals that function best in their environment tend to leave the most offspring(when this process repeats over time, each new generation has a higher proportion of individuals with traits that give them an advantage)
what was Darwin’s thought on natural selection?
that natural selection could eventually cause isolated populations of the same species to become separate species as they adapted to their different environments (supported by artificial selection)
what does the frequency of an allele refer to?
it refers to how often it occurs in a gene pool
what are 3 factors that can change a gene pool without leading to adaptation?
genetic drift, gene flow, and fitness
How does the theory of evolution help scientists?
it helps scientists better understand certain inherited and infectious diseases
Why is it good to have one copy of the sickle cell allele in the African population?
bc with one allele they become resistant to the disease malaria
