If the root equi- means "equal," what does equinox mean?
a) the same temperatures for a period of time
b) the same distance from the north pole and south pole
c) when the length of day and the length of night are the same

Exit what always affects measurement error in an experiment? a. investigator bias b. variability in nature c. instrument precision d. misreading the instrument

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

Which of these is a major trend in land plant evolution? a) the trend toward smaller size b) the trend toward a gametophyte-dominated life cycle c) the trend toward a sporophyte-dominated life cycle d) the trend toward larger gametophytes