Is it unusual to find elevated levels of iridium in the geologic layer at the K–T boundary?
a. Yes, iridium is a common metal on Earth but rarely accumulates in a singe layer.
b. No, iridium is a rare element on Earth, but geological layers of iridium are not uncommon.
c. Yes, iridium is a rare metal on Earth.
d. Yes, composition differences between geological layers tend to equilibrate over time.
C
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The drug PCP (angel dust) elicits its actions by blocking the elimination of biogenic amines from the synapse.
Answer the following statement true (T) or false (F)
What factor has been implicated as a trigger for the formation of artery-blocking plaques?
a. allergies b. inflammation c. hypertension d. blood clots e. low blood fats
Which of the following are NOT energy reserves?
A) carboxysomes B) polysaccharide granules C) lipid inclusions D) ribosomes E) metachromatic granules
In microarrays, the oligonucleotides that are attached have the fluorescent tag, whereas the DNA fragments being tested do not
A. true B. false