CHAPTER 8- THE CELLULAR BASIS OF ACTIVITY UNIT 3- ENERGY, MATTER, AND ORGANIZATION: RELATIONSHIPS IN LIVING SYSTEMS CHAPTER 8- THE CELLULAR BASIS OF ACTIVITY

Matter- Anything that occupies space and has mass. Energy- The ability of a system or matter to do work. Determined by the breaking and forming of chemical bonds. Energy is required for all cellular biochemical reactions in a body. Energy causes molecules in the cells to be rearranged. This is a matter-energy relationship for biology. Element- A substance consisting of the same type of atom and that can’t be broken down to form any simpler kinds of matter. Atom- The basic building blocks of all matter. The simplest particle of an element that retains all of the properties of that element. Molecule- A chemical structure composed of one or more atoms or elements.

Chemical Bonds- Forces that hold atoms or elements together in a predictable way. Forces that store energy in molecules. Exothermic Reaction- Chemical reactions that release heat due the rearranging of molecules. Endothermic Reaction- Chemical reactions that absorb heat due to the rearranging of molecules. Potential Energy- Energy that is stored in the structure of matter and is available for use. Kinetic Energy- Energy that is active and due to the motion of matter.

Synthesis- A chemical reaction where two or more smaller molecules are joined together to form a larger molecule. Decomposition- A chemical reaction where a larger molecule is broken down into two or more smaller molecules. Adenosine Triphosphate (ATP)- The molecule that is commonly used as a direct source of energy by organisms. A molecule that is broken down from large, long term storage molecules, like glycogen, into a smaller form that can be used as a direct source of energy.

Food- Material (matter), usually of plant or animal origin, that contains or consists of essential body nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals, and is ingested and assimilated by an organism to produce energy, stimulate growth, & maintain life

calorie- The unit of measurement used to designate the amount of energy contained in food or the amount of energy an organism uses to operate. The amount of energy needed to raise 1 gram (milliliter) of water 1 Celsius. When looking at food, calories are given in kilocalories (1,000 calories), written with a capital Calories. If a food says it has 200 Calories per serving, that means it really has 200 kilocalories or 200,000 calories.

FOOD (ORGANIC) MACROMOLECULES Carbohydrates (bread, pasta, fruit, dairy, candy)- provide much of the energy that cells need. The building blocks of carbohydrates are glucose molecules. Their chemical structure is in a 1:2:1 ratio of C:H:O. They are also called saccharides Mono- 1- glucose, fructose Di- 2- sucrose Poly- many- starch Carbs must be broken down to their simplest form (glucose) in order for cells to use them.

FOOD (ORGANIC) MACROMOLECULES Lipids (fat, oils)- organic substances that are insoluble in water, but break down in organic solvents. The building blocks of lipids are fatty acids and glycerol. Lipids are what carbs turn into when you don’t use them They are much harder to break down and metabolize

FOOD (ORGANIC) MACROMOLECULES Proteins (meats, nuts, dairy)- serve as structural material and quick energy sources. The building blocks of proteins are amino acids Proteins serve as enzymes, molecules that help speed up metabolic reactions Proteins are the building blocks of the body, but don’t provide much lasting energy as food