How does testosterone cross the plasma membrane?
a. simple diffusion,
b. passive transport through a carrier protein,
c. active transport,
d. co-transport.

Most of earth’s fresh water is found in oceans and seas stored in glaciers and ice caps groundwater stored beneath the surface found in lakes, rivers, streams, and reservoirs

Which of the following statements is true? 1. the mantle of the earth is made of solid nickel and iron. 2. the crust of the earth is made of solid nickel and iron. 3. the inner core is made of solid nickel and iron.

If bacteria are much too small to see, what is one reason why can we see colonies in the petri dishes that have plenty of food to eat after only a few days?