1. What is the role of a receptor in helping an organism maintain homeostasis?
A. receives messages sent by the control center
B. carries out a response to restore internal
conditions
C. detects stimuli and sends information to the
control center
D. compares current conditions with ideal values
for those conditions

igneous rocks which formed by the crystallization of magma at the surface of the earth called extrusive rocks. they are characterized by fine-grained textures because the rapid cooling at or near the surface did not provide enough time for large crystals to grow.

the rocks are classified by the geological process they are formed by. the three main groups of rocks are igneous, metamorphic, and sedimentary. minerals are not they are classified under the chemical classes they are in. these groups include silicates, sulfates and carbonates.