| Questions | 5 |
| Topics | Central & Peripheral Nervous Systems, Exoskeleton, Health Benefits of Vitamins & Minerals, Meteoroids, Terrestrial Planets |
The nervous system consists of the brain and spinal cord (central nervous system) and the peripheral nervous system which is the network of nerve cells (neurons) that collect and distribute signals from the central nervous system throughout the body.
An exoskeleton (external skeleton) is common in arthropods like insects, spiders, and crustaceans.
| 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. |
Smaller rocks shed by asteroids and comets are called meteoroids. When these rocks reach Earth's atmosphere, they burn up in the mesosphere and become meteors. If a meteor manages to reach the Earth, it is called a meteorite.
The four planets closest to the Sun (Mercury, Venus, Earth, and Mars) are called terrestrial (Earth-like) planets because, like the Earth, they're solid with inner metal cores covered by rocky surfaces.