Over the past 580 million years, how has biodiversity changed?
A) It has smoothly and steadily increased.
B) It has smoothly and steadily increased until the past 100 years or so.
C) It has generally increased but with punctuations in the pattern.
D) It has rapidly increased until it started to rapidly decrease in the past 100 years or so.
C
You might also like to view...
Which of the following is not a typical occurrence in the history of a transposon's appearance in an organism?
A. Transposons could be dispersed to a new host cell by conjugation, viral infection, or accidental uptake of DNA by the cell. B. After its introduction into the new host cell, the transposon is likely to experience a period of high transposition activity. This activity is unlikely to be detrimental to the host cell. C. After introduction into the new host cell, the transposon is likely to increase its copy number. D. Eventually, the transposon becomes subject to silencing processes including mutations in the transposase gene. E. The host may find a way to shut down transposition. One common method is RNA interference.
Which of the following is a major finding from the ENCODE project?
A. DNA methylation usually signifies the activation of gene expression B. In humans, one gene encodes exactly one protein. C. Gene regulation is achieved through a complex network of regulatory regions throughout the genome. D. Less than 20% of human DNA is linked to biological function. E. There are more than 10 million regulatory sites in human DNA.
Muscle cells are stimulated by acetylcholine released from the terminals of
A. transverse tubules. B. motor cell axons. C. sensory cell axons. D. motor cell dendrites. E. sensory cell dendrites.
Mycorrhizae are ____
a. the small roots in the root systems of trees b. endosymbiotic bacteria associated with plant roots c. fungus and root mutualistic associations d. parasitic fungal infections of tree roots e. endosymbiotic fungal cells associated with leaves