Barbiturates are
a. depressants.
b. stimulants.
c. analgesics.
d. hallucinogens.
e. antipsychotics.
Answer: a
You might also like to view...
The topoisomerase ________ introduces positive supercoils in DNA, which stabilizes DNA and prevents the DNA helix from denaturing at high temperatures
A) reverse ligase B) ligase C) DNA gyrase D) reverse DNA gyrase
There are many examples of unusual plants, such as the pitcher plant that you have studied in
Chapter 13. Another highly unique plant is the Hydnora africana, which is indigenous to deserts in southern Africa. The only portion of this plant that is visible above ground is a fairly large fleshy orange and brown flower. There are no leaves or stems evident, but it has an extensive root system that intertwines with the roots of another type of plant. Explain the unusual lifestyle of this species. In addition, name a macronutrient that would not be needed by this plant as much as it would in a traditional plant.
What will be an ideal response?Echinoderms can be best described as ________.
A. eukaryotic autotrophs that lack tissue, but have bilateral symmetry as larva, and a water vascular system B. eukaryotic heterotrophs with tissue, bilateral symmetry as larva, and a water vascular system C. eukaryotic autotrophs with tissue, bilateral symmetry as larva, and a water vascular system D. eukaryotic heterotrophs with tissue, bilateral symmetry as larva, and a blood vascular system
Genetic drift results in a change in allele frequencies because
A) gene flow within the population allows alleles to flow between populations. B) the population has not yet stabilized. C) the population size is so small that chance occurrences can alter allele frequencies. D) the population is so large that natural selection has little noticeable effect.