Question | Answer |
Vestigal Structures | structures such as bones that are no longer necessary for an organism to live |
Evolution | accumulated small changes over time by a species |
mutation | any change in the DNA sequence |
trait | physical thing that can be seen about an organism |
selective breeding | man chooses which traits to breed for such as seedless grapes or juicer tomatoes |
speciation | process of natural selection where a species becomes seperated to the extent they adapt to their new surroundings to the point that they can no longer interbreed. therefore they are new species |
S.A.D. | seperate, adapt, division |
adaptation | changes in an organism that allow it to better survive in its surroundings |
fossil | imprint or fossilized bones of an organism. Conditions must be just right. Layers of fine sedimentation plus NO oxygen. Explains why there are gaps in the fossil record. |
genetic variation | differences in individuals in a species. this allows some individuals to be more succesful than others |
natural selection | process that includes four steps. Environment determines what traits will be passed down |
What can insects do? | They can adjust very quickly because their generation time is very short |
What is the difference between natural selection and selective breeding? | In selective breeding, man chooses the traits to be passed on. In natural selection, the environment chooses what traits will be passed on. |
Describe the four steps involved in natural selection. | 1. Overproduction- species produces more offspring then will survive to adulthood
2. genetic variation- each individual has different traits. Some of theses traits help the individual survive and pass these traits on. others die out |
Describe the four steps involves in natural selection cont. | 3. struggle to survive - not enough food, water, ect. to go around. Those individuals who have traits that are best adapted to their environment will survive.
4. Succesful reproduction - individuals with the best traits that have allowed them to better |
Describe the four steps involves in natural selection cont. | adapt to their surroundings will survive to mate and pass on these traits |
Explain what happened with the number of European peppered moths after 1850. | Many birds eat peppered moths that are on tree trunks. Before the 1850s the trees had a gray look, pale peppered moths blended in. Dark peppered moths were eaten more. After the 1850s, soot and smoke from polution covered the trees. Now the dark peppered |
Explain what happened with the number of European peppered moths after 1850 cont. | moths blended in and the pale peppered moths showed against the black tree trunks. |