Answer:
B: It occurs only in cells in the reproductive structures of organisms.
Explanation:
A. they arose out of Africa less than 200,00 years ago
Answer:
The speed at which the reactants change to products over a given time.
Explanation:
A chemical's <u>reaction rate</u><u> is the change in the concentration of a reactant or a product with time (in moles per second)</u>.
Remember that during a chemical reaction, reactants are converted to products. Or what is the same, products are formed at the expense of reactants. This can be represented:
reactants → products
Therefore,<u> the progress of a reaction can be followed measuring the decrease in concentration of the reactants or the increase in concentration of the products.</u>
According to the temperature and other parameters, the reaction rate can increase or decrease.
Answer:
a free encyclopedia...but probably best not to use it cos apparently anyone can just edit it