| Questions | 5 |
| Topics | Cell Membrane, Fiber, Health Benefits of Vitamins & Minerals, Refraction, Somatic Nervous System |
Animal cells are surrounded by a semipermeable membrane which allows for the transfer of water and oxygen to and from the cell. In plant cells, the cell membrane is surrounded by a somewhat rigid cell wall which provides the cell structure and support.
Fiber provides bulk to help the large intestine carry away waste. Good sources of fiber are leafy vegetables, beans, potatoes, fruits, and whole grains.
| 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. |
Because different materials have different refractive indices, light changes speed when passing from one material to another. This causes the light to bend (refraction) at an angle that depends on the change in refractive index between the materials. The greater the difference, the higher the angle of refraction.
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.