| A | B |
|---|
| Nitrogen Fixation | the process by which bacteria change free nitrogen so that nitrogen atoms can combine with other elements to form compounds that organisms can use |
| Pollution | Any change in the environment that produces a condition that is harmful to living things, eg. smog |
| Fertilizer | A substance that enriches soil so that plants will grow better. |
| Pesticides | Chemicals used to kill pests. |
| Pest | An organism that harms people, crops, or structures. |
| Herbicides | Chemicals used to control weeds. |
| Insecticides | Chemicals used to kill or control insects. |
| Fungicides | Chemicals used to kill or control fungi. |
| Sewage | Wastewater containing dissolved and undissolved materials from your kitchen, bathroom and laundry. |
| Septic Tank | Underground container where bacteria break down the organic materials before they are moved out to the soil. |
| Sewage Treatment Plant | Treats wastes from homes, businesses, industries and institutions. |
| Fossil Fuels | Fuels such as coal, oil and natural gas that are formed from dead plants and animals over millions of years. |
| Sour Gas | Natural gas that contains hydrogen sulfide. |
| Acid | A compound that dissolves in water to form a solution with a pH lower than 7. |
| pH | A measure of the concentration of hydrogen ions in a solution. |
| Base | A compound that dissolves in water to form a solution with a pH higher than 7. |
| Neutral Solution | A solution that has a pH of 7 - neither acid nor base. |
| Neutralization Reaction | A reaction of an acid with a base which produces a salt and water. |
| Nutrients | Elements and compounds that organisms need for living, growing, and reproducing. |
| Macronutrients | Nutrients that are needed in relatively large amounts. |
| Micronutrients | Nutrients that are needed in only minor or trace amounts by the body. |
| Carbohydrates | Organic molecules made up of atoms of carbon, hydrogen and oxygen - form molecules such as glucose or starch. |
| Lipids | Organic molecules such as fats, oils, and waxes. |
| Proteins | Organic molecules that are used by organisms for growth and repair and as a source of energy. |
| Amino Acids | The building blocks of proteins. |
| Nucleic Acids | Large, complicated molecules that make up DNA and RNA. |
| Diffusion | The movement of molecules from an area of high concentration to an area of low concentration. |
| Osmosis | The process by which water moves across a semi-permeable membrane from an area of high concentration to an area of low concentration. |
| Active Transport | The process by which organisms use energy to move substances from an area of low concentration to an area of high concentration. |
| Hydrolysis | Reaction of a substance with water - using water to break a large molecule down into a smaller molecule. |
| Substrate | The material on which an organism lives or moves. |
