| Questions | 5 | 
| Topics | Acidity, Fahrenheit Scale, Health Benefits of Vitamins & Minerals, Somatic Nervous System, Types of Rock | 
An acid is a substance that gives up positively charged hydrogen ions (H+) when dissolved in water. A base (alkaline) gives up negatively charged hydroxide ions (OH-) when dissolved in water. pH is a scale that measures of how basic or acidic a solution is. Numbered from 0 to 14, solutions with a pH of 7 are neutral, less than 7 are acidic, more than 7 are alkaline.
More familiar in the United States is the Fahrenheit scale in which the freezing point of water is 32°F (0°C) and the boiling point is 212°F (100°C). To convert from C° to F° use the formula:
\(F° = {9 \over 5}C° + 32\)
and to convert from F° to C° use:
\(C° = {5 \over 9} (F° - 32)\)
| Vitamin / Mineral | Sources | Health Benefits | 
|---|---|---|
| Calcium | Dairy products (milk, yogurt, cheese), spinach. | Aids bone growth and repair, muscle function. | 
| Iron | Red meat, beans, whole grains. | Allows red blood cells to transfer oxygen to body tissues. | 
| Magnesium | Nuts, whole grains, green leafy vegetables. | Muscle, nerve, and enzyme function. | 
| Potassium | Bananas, nuts, seeds. | Helps balance fluid levels in the body. | 
| Vitamin A | Liver, milk, eggs, carrots. | Vision, immune system, cell growth. | 
| Vitamin C | Green and red peppers, citrus fruits, broccoli. | Collagen formation, immune system function, antioxidant (helps protect cells from damage). | 
| Vitamin D | Exposure to sunlight. | Helps calcium strengthen bones, muscle, nerve, and immune system function. | 
Part of the peripheral nervous system, the somatic nervous system is made up of nerve fibers that send sensory information to the central nervous system and control voluntary actions.
The Earth's rocks fall into three categories based on how they're formed. Igneous rock (granite, basalt, obsidian) is formed from the hardening of molten rock (lava), sedimentary rock (shale, sandstone, coal) is formed by the gradual despositing and cementing of rock and other debris, and metamorphic rock (marble, slate, quartzite) which is formed when existing rock is altered though pressure, temperature, or chemical processes.