When a snail is touched it retreats into its shell. this is an example of

the answer is

c. parental

i have to report this, it doesn't relate to biology

it's the cell cycle, but cytokines is when the cell divides.

theres 3 stages interphase,mitosis,and cytokines.

interphase prepares the cell for division.

mitosis is the process of dividing the cell,it has 4 parts interphase,anaphase,metaphase,and telophase.

lastly there's cytokines,that's when the cell divides into 2 daughter cells

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.