Which of the following is neutrally charged ?
a) an ion
b) a compound
c) an electron
d) a proton

stimulus is a change in the environment that causes an organism to react. the response is the reaction to the stimulus. some examples of stimuli for zebras are drought, to many predators, and bad feeding grounds such as dead grass or plants. zebras respond to stimuli just like all other living organisms

ionic bonds are two oppositely charged ions that attract. a sodium ion has a 1 positive charge; a chloride ion has a 1 negative charge. sodium and chloride have oppostive charged ions that attract which forms an ionic bond. a chemical bond formed when two atoms share electrons is called

which

what is a measurement of the earth’s history divided into time periods?

> fossil record <

sedimentary rock

> geologic time scale <

radioactive elements