Answer the following question given this paragraph: H2 + O2 H2O This is an example of a chemical equation, which is a concise way of representing a chemical reaction. The initial substances are called reactants, and the final substances are called products. Unfortunately, it is also an incomplete chemical equation. The law of conservation of matter says that matter cannot be created or destroyed. In chemical equations, the number of atoms of each element in the reactants must be the same as the number of atoms of each element in the products. If we count the number of hydrogen atoms in the reactants and products, we find two hydrogen atoms. But if we count the number of oxygen atoms in the reactants and products, we find that there are two oxygen atoms in the reactants but only one oxygen atom in the products. What can we do? Can we change the subscripts in the formula for water so that it has two oxygen atoms in it? No; you cannot change the formulas of individual substances because the chemical formula for a given substance is characteristic of that substance. What you can do, however, is to change the number of molecules that react or are produced. We do this one element at a time, going from one side of the reaction to the other, changing the number of molecules of a substance until all elements have the same number of atoms on each side. To accommodate the two oxygen atoms as reactants, let us assume that we have two water molecules as products:. Q: Initial substances are called reactants, and the final substances are called what? Choices: - exports - imports - reactors - products A:
products

Answer the following question given this paragraph: Homeostasis refers to the balance, or equilibrium within the cell or a body. It is an organism's ability to keep a constant internal environment. Keeping a stable internal environment requires constant adjustments as conditions change inside and outside the cell. The adjusting of systems within a cell is called homeostatic regulation. Because the internal and external environments of a cell are constantly changing, adjustments must be made continuously to stay at or near the set point (the normal level or range). Homeostasis is a dynamic equilibrium rather than an unchanging state. The cellular processes discussed in this lesson all play an important role in homeostatic regulation. More concerning homeostasis will be presented in additional concepts. Q: What is the name of the process that refers to the balance or equilibrium within the cell or a body? Choices: - static - hypothesis - determinants - homeostasis A:
homeostasis

Answer the following question given this paragraph: The modern atomic theory states that all matter is composed of atoms. Q: The modern atomic theory states that all matter is composed of what? Choices: - ions - quarks - molecules - atoms A:
atoms

Answer the following question given this paragraph: Bile salts are bile acids that help to break down fat. Bile acids are made in the liver. When you eat a meal, bile is secreted into the intestine, where it breaks down the fats ( Figure below ). Q: In which organ are bile acids made Choices: - spleen - kidney - gall bladder - liver A:
liver