Muscles in animals are often found in pairs, because
a. muscles can only pull.
b. muscles need to be able to both push and pull.
c. muscles can only push.
d. muscles can only produce a force as they relax.

Why are small quantities of chlorofluorocarbons so harmful to the ozone layer? a. the chlorofluorocarbons act like ultraviolet radiation causing large amount of ozone to be produced. b. the chlorine from the chlorofluorocarbons reacts with free molecules of oxygen causing a stop in ozone production c. free oxygen atoms can replace the chlorine in chlorine monoxide, releasing a free atom of chlorine which can then recombine with an oxygen atom in ozone, destroying more ozone. d. chlorofluorocarbons absorb ultraviolet radiation, preventing the formation of ozone select the best answer from the choices provided

Osmosis is often viewed incorrectly as a process driven directly by differences in solute concentration across a selectively permeable membrane. what really drives osmosis? view available hint(s)osmosis is often viewed incorrectly as a process driven directly by differences in solute concentration across a selectively permeable membrane. what really drives osmosis? the first law of thermodynamicsthe difference in the height of water columns on either side of a selectively permeable membranethe difference in water concentration across a selectively permeable membranethe difference in sugar or ion concentration across a selectively permeable membrane

What is used to keep track of the gamates and possible offsprings combination