The ancient earth did not contain much oxygen
a. true
b. false
Answer: a. true
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A major explosion of animal diversity in which all major marine lineages were formed took place during which period?
a. Cambrian b. Carboniferous c. Devonian d. Permian e. Proterozoic
Which of the following releases substances that
initiate blood clotting? a. lymphocytes b. basophils c. erythrocytes d. neutrophils e. platelets
The Antarctic icefishes are the only known vertebrates to lack hemoglobin. Which of the following would be LEAST likely to alter gas transport from the environment to an icefish's cells?
A) higher oceanic temperatures from global warming B) higher concentrations of carbon monoxide in the water from pollution C) higher concentrations of carbon dioxide in the water from pollution D) an injury that reduces the surface area of gills
In the sexual selection simulation you looked at what happens if some organisms can evolve preferences for some traits, even when those traits have no intrinsic effect on the fitness of the organisms. What happened to the size of the organisms over time when you set the LEK-SIZE to 2 or even as high as 10 (really intense sexual selection)?
A. It remained unchanged B. It increased rapidly C. lt decreased rapidly