The topsoil layer has the greatest concentration of organic matter. the subsoil generally lacks organic matter, but it does receive small clay particles and dissolved ions that wash downward from the topsoil. the c horizon is made of materials weathered directly from the parent material, which lies immediately below. the parent material is either solid bedrock or a layer of sediment. based on this information, a. all three of these layers should have the same texture. b. the subsoil likely has a rockier texture than the topsoil and c horizon. c. the topsoil likely has a rockier texture than the subsoil and c horizon. d. the c horizon likely has a rockier texture than the topsoil and subsoil.

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.

in a chemical reaction, the atoms and molecules produced by the reaction are called products. no new atoms are created, and no atoms are destroyed. in a chemical reaction, reactants contact each other, bonds between atoms in the reactants are broken, and atoms rearrange and form new bonds to make the products.

all these collisions do one thing, and that thing is explained in the last option. when dusst, rocks and ice collide, they harden and form giant layers of rocks or hard ice.

d)   to harden materials to form different parts of earth’s layers

hope it ,

bioteacher101

a. 35°c

b. 25°c

c. 10°c

d. 40°c