| Questions | 5 |
| Topics | Autonomic Nervous System, Decomposers, Medulla, Moon, Prefixes |
Part of the peripheral nervous system, the autonomic nervous system regulates involuntary activity in the heart, stomach, and intestines.
Decomposers (saprotrophs) are organisms such as bacteria and fungi that break down the organic matter in the dead bodies of plants and animals into simple nutrients.
Part of the brainstem, the medulla is the connection between the brain and the spinal cord. It controls involuntary actions like breathing, swallowing, and heartbeat.
Tides are caused by the gravitational interaction of Earth and the Moon.
A prefix is added to the base units of the metric system to indicate variations in size. Each prefix specifies a value relative to the base unit in a multiple of 10. Common prefixes are:
| Prefix | Symbol | Relative Value | Example |
|---|---|---|---|
| mega | M | 106 (1,000,000) | Mm |
| kilo | k | 103 (1,000) | km |
| base unit | N/A | 1 | m |
| centi | c | 10-2 (1/100) | cm |
| milli | m | 10-3 (1/1,000) | mm |