Which structure can be used to differentiate eukaryotic cells from prokaryotic cells?
a- nucleus
b- ribosome
c- nucleic acid
d- plasma membrane

Which of the following types of pollution is most responsible for large numbers of deaths worldwide because of unsafe drinking water? (a) nutrient pollution (b) thermal pollution (c) pathogen pollution (d) sediment pollution

Which of these is one of the nitrogenous bases in dna? a. proline b. leucine c. glycine d. thymine

Why are some places regularly warmer or cooler than others in a given month