Which of the following correctly describes the size of meteoroids? a. meteoroids are smaller than comets but larger than asteroids. b. meteoroids are smaller than asteroids but larger than comets. c. meteoroids are smaller than comets and asteroids. d. meteoroids are larger than comets and asteroids.

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.

phaneritic textures in which phaner means visible so phaneritic textures are standard of impertinent volcanic rocks. these rocks crystallized gradually under the surface of earth. when the magma cools deliberately then the ores have chance to develop and produce long crystals.