Anaphylactic shock ________
A) occurs when blood vessels constrict abruptly
B) is a symptom of an immunodeficiency disease
C) causes blood pressure to drop dangerously
D) has no treatment
C
You might also like to view...
Robert Paine was the first biologist to use the term keystone species in the 1960s. He was
studying food webs in the rocky, intertidal pools in the Pacific Northwest. At one of his study
sites, the dominant organisms in the tidal pools were mussels, barnacles, whelks, and a species
of starfish known as Pisaster ochraceus. To examine the relationship between these species,
Paine set up an experiment. In one area, he removed all the starfish from the tidal pools, and
in an adjacent area, he left the tidal pools as he found them. Prior to removing the starfish, he
sampled all the organisms in each pool. After two months, he repeated this sampling. A
summary of his results is illustrated in the graph below.
Tendon sheaths
What will be an ideal response?
In 2004, Jun-Yuan Chen and David Bottjer found a fossil approximately 580-600 million years old. Why was this particular fossil significant?
A. It was one of the earliest fossils of a single-celled organism. B. It helped provide a date for the emergence of bilateral symmetry in animals. C. It provided evidence that the earliest life forms were heterotrophic. D. It provided evidence that the earliest life forms were autotrophic. E. It helped provide a date for the emergence of vertebrates.
Which is the only group of microorganisms that contains lipopolysaccharides (LPS)?
a. Archaea b. Bacteria c. gram-positive bacteria d. gram-negative bacteria