Answer the following questions in reference to the four geologic periods listed below.
A. Asteroid impact at the K-T boundary caused extinctions.
B. Human practices are the major agents of extinction.
C.
D. Volcanic activity in what is now Siberia released a large amount of carbon into the atmosphere causing extinctions.
E. Oceans became anoxic, and methane burned on land.
F. The greatest mass extinction event where 90 to 95 percent of all species were lost
A. Cretaceous
B. Anthropocene
C. Devonian
D. Permian
E. Permian
F. Permian
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Estrogen is a lipid soluble hormone that can easily cross membranes. Knowing this, what can be concluded about estrogen receptors?
A. The receptors would be coupled to a G-protein. B. The receptors would be linked to enzymes that triggered a kinase cascade. C. The receptors would be found inside the cell. D. The receptors would be on the plasma membrane. E. The receptors would also be lipid soluble and able to cross membranes.
Which step in producing ATP is correctly paired with the location where it occurs?
A) Krebs cycle—mitochondrial matrix B) formation of an electrochemical gradient—cytoplasm C) glucose is broken down to produce pyruvate—space between inner and outer mitochondrial membranes D) electron transport chain—outer mitochondrial membrane E) breakdown of pyruvate to form NADH and FADH2—cytoplasm
The entire DNA sequence of a species is called its ________.
Fill in the blank(s) with the appropriate word(s).
Several groups of protists have variable modes of nutrition: Some species are photoautotrophs, whereas close relatives are heterotrophs. Such diversity even exists within a single species in some cases. Evidence suggests that this pattern is a result of the __________.
Fill in the blank(s) with the appropriate word(s).