test 2 Flashcards
in a controlled experiment _____ variable(s) is/are allowed to change. That/those variable(s) is/are called____ variable(s).
1, controlled
Sagan suggests that what provides certain evidence to the “fact” of evolution?
artificial selection; natural selection; the fossil record; shared organic chemistry, especially the genetic code of nucleic acids.
As described in lecture, the Bullock’s and Baltimore Orioles produced hybrid offspring in areas where their populations overlapped, leading researchers to believe they were ____, but the hybrids molted twice in the molt season, requiring greater energy, thus making the hybrids____, and therefore _____:
one single species, sterile, two separate species
what is convergent vs divergent evolution
convergent evolution is evolution of similar features in species of different periods of time/ habitats due to similar environmental adaptations
divergent evolution is when species sharing a common ancestry become more distinct due to differential selection pressure which gradually leads to speciation
As the evolution of the species of cichlids in Figure 1-3 occurred in two different lakes, separated by Victoria Falls, this stands as a good example of:
convergent evolution
sympatric speciation is
same species and same habitat but separated by actions so they split and turn into 2 diff species
allopatric speciation
occurs when geographically separate populations may evolve independently through mutation, natural selection, and genetic drift.
What is the result of the expansion of the oceanic plates in the Atlantic Ocean?
Oceanic crust, being more dense, dives below the continental crust.
2) Tremendous heat and pressure from the diving (subducting) crust causes volcanoes near the continental margins.
When mantle material is heated by the Earth’s core, it becomes ___ and ___ to the crust, where it strikes, spreads side-to-side, ___ to become ___ and ___.
less dense, rises, cools, more dense, repeat???
Briefly describe the origin of life on Earth as explained by current scientific theory.
1.earth formed as a rocky, sterile ball
2.violent volcanism led to formation of atmosphere
3. condensation of water vapor formed seas
4. organic materials were synthesized from atmospheric gases from violent electric storms and lightning
5. 4 billion years ago the first living things (bacteria) appear in oceans
6. photosynthesis by early organisms contributed O2 to atmosphere
7. ozone layer formed in upper atmosphere (blocks uv radiation)
8.life spread to shallow coastal waters and eventually to dry land
Describe the steps of the scientific method
- observations
- data is gathered from observations made or facts gathered
3.hypothesis is formed as possible explanation to phenomenon
4.controlled experiment is developed and preformed to test hypothesis - conclusions are made concerning problems and accuracy of hypothesis based on results of hypothesis
6.with repeated testing a theory may be developed
List and describe 4 life processes.
reproduction: reproducing organisms of their own species whether by sexual reproduction or asexual reproduction
transportation: organisms control movement of materials in and out of cells
respiration: when chemical energy from nutrients are released and oxygen/CO2 is brought in (depending on if plant or animal)
synthesis: when organisms combine simple substances to form complex substances
Natural selection acts on the ___ whereas evolution has a ___effect
individual, population
