Which of the following is the most likely cause for the sudden sharp increase in atmospheric carbon dioxide levels?
A. natural events, including fires and volcanic activity
B. normal fluctuations in the natural levels of carbon dioxide in the atmosphere
C. human activities, including the use of fossil fuels, changes in agricultural practices, and deforestation
D. respiration from the earth's many living organisms
Answer: C
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True or False: In order to attract the opposite sex, sensory hairs in the silkworm moth, Bombyx, allow ion channel receptors to open, and ultimately electrical signals are conducted as action potentials following a response to airborne chemicals
A. true B. false
How can repositioning nucleosomes affect transcription (select all correct choices)?
A. Moving nucleosomes could expose a promoter resulting in repression of transcription. B. Moving nucleosomes could cover a promoter resulting in repression of transcription. C. Moving nucleosomes could expose a promoter resulting in activation of transcription. D. Transcription is not affected by repositioning of nucleosomes.
When two traits are analyzed separately, then the frequencies of each are combined to yield the observed phenotypic
ratios, this confirms the principle of ____________________. Fill in the blank(s) with the appropriate word(s).
The death rate of organisms in a population exhibiting a Type III survivorship curve is:
a. usually correlated with density-independent causes. b. more or less constant throughout their lives. c. lower after the organisms survive to the critical age of establishment.