The restriction enzymes of bacteria protect the bacteria from successful attack by bacteriophages, whose genomes can be degraded by the restriction enzymes
The bacterial genomes are not vulnerable to these restriction enzymes because bacterial DNA is methylated. This situation selects for bacteriophages whose genomes are also methylated. As new strains of resistant bacteriophages become more prevalent, this in turn selects for bacteria whose genomes are not methylated and whose restriction enzymes instead degrade methylated DNA. The outcome of the conflict between bacteria and bacteriophage at any point in time results from _____. A) frequency-dependent selection
B) evolutionary imbalance
C) heterozygote advantage
D) neutral variation
A
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In nature, the major mechanism of introducing new genes into eukaryotic genomes is _____
A) duplication followed by evolutionary divergence B) unequal crossing over at microsatellite repeats C) pseudogene creation D) pseudogene restoration
What is the name of the field of biology that compares the development of different organisms in an attempt to understand ancestral relationships between organisms and the developmental mechanisms that bring about evolutionary change?
A. Pattern formation. B. Punctuated equlibrium. C. Cell biology. D. Evolutionary developmental biology. E. Endocrine biology.
In ascomycetes and basidiomycetes, plasmogamy is followed immediately by karyogamy
____________________ Indicate whether the statement is true or false.
Pasteurization is a technique in which heat is applied to liquids to kill potential agents of infection and spoilage, while at the same time retaining the liquid's flavor and food value.
a. true b. false