Smallpox is in its MOST contagious phase when:
A) a rash develops.
B) blisters begin to form.
C) the patient becomes febrile.
D) a headache and body aches develop.
Answer: B) blisters begin to form.
You might also like to view...
Suppose you are studying the nitrogen cycling in a pond ecosystem over the course of a month. While you are collecting data, a flock of one hundred Canada geese lands and spends the night during a fall migration
What could you do to eliminate error in your study as a result of this event? A) Find out how much nitrogen is consumed in plant material by a Canada goose over about a twelve-hour period, multiply this number by 100, and add that amount to the total nitrogen in the ecosystem. B) Find out how much nitrogen is eliminated by a Canada goose over about a twelve-hour period, multiply this number by 100, and subtract that amount from the total nitrogen in the ecosystem. C) Find out how much nitrogen is consumed and eliminated by a Canada goose over about a twelve-hour period and multiply this number by 100; enter this +/- value into the nitrogen budget of the ecosystem. D) Do nothing. The Canada geese visitation to the lake would have negligible impact on the nitrogen budget of the pond. E) Put a net over the pond so that no more migrating flocks can land on the pond and alter the nitrogen balance of the pond.
Adaptive radiation is
a. the basis of radiometric dating. b. development of similar body form in unrelated organisms. c. formation of beneficial alleles through exposure to radiation. d. origin of many species from a single common ancestor. e. spread of successful alleles from one population to another.
What compound is found at the reaction center of a photosystem?
A) chlorophyll b B) carotenoids C) phycobilins D) chlorophyll a
Which of the following is an example of artificial selection?
a. scientists have bred strains of the house mouse that are missing certain alleles. These strains were produced in the laboratory to allow scientists to study diseases that occur in humans. b. The ancestor of broccoli was weedy looking plant that looks very different than broccoli. Farmers selected plants with large stems and flowers and used their seeds to produce the next generation. Over time this became what we now call broccoli. c. Long ago people started to keep wild cats and bred the most docile ones. After many generations of doing this and selecting for traits that people liked, we now have domestic house cats. d. all of these