Vaccinations were first invented using cowpox to protect against smallpox in the 1700s
a. true
b. false
Ans: a. true
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The protein-coding gene sequences in humans and chimpanzees
A. are vastly different. B. are about 50% alike. C. are about 80% alike. D. are more than 99% alike. E. are identical.
Which of the following are accessory pigments
in photosynthesis? a. carotenoids b. phycobillins c. anthocyanins d. chlorophyll b e. all of these
In a woody stem, the vascular cambium is located directly below the outer bark
1.True
2.False
Which is not an example of virulence as an evolving property?
A) Cold viruses which generate more coughs and sneezes while allowing the host to remain mobile will have an evolutionary advantage over those that cause their host to be bedridden. B) As hosts evolve more effective defenses against a given pathogen, the pathogen in turn will evolve virulence factors to combat those defenses. C) The 1918 influenza pandemic primarily killed young adults rather than elderly persons which is more typical of influenza both before and after that time. D) Historically, smallpox appeared to shift from a highly virulent pathogen which killed its victims quickly to one that did not kill immediately but more easily spread from person to person. E) Each of these is an example of virulence as an evolving property.