Five new species of bacteria were discovered in Antarctic ice core samples. The nucleotide (base) sequences of rRNA subunits were determined for the new species. The table shows the number of nucleotide differences between the species

Astudent poured a solution of bromothymol blue indicator into three test tubes. then he placed an aquatic plant in two of the test tubes, as shown below. he placed a stopper on each test tube and placed them all in the dark for 24 hours. bromothymol blue turns from blue to yellow in the presence of co2

Organisms may contain up to five levels of organization within their bodies. which level of organization is shown by the liver? a. tissue b. organ c. organism d. organ system

What determines whether a particular cell is able to respond to a hormone?