ASVAB General Science Practice Test 355300

Questions 5
Topics Medulla, Prefixes, Primary Consumers, Proton, Refraction

Study Guide

Medulla

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.

Prefixes

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
Primary Consumers

Primary consumers (herbivores) subsist on producers like plants and fungus. Examples are grasshoppers, cows, and plankton.

Proton

A proton is a subatomic particle found in the nucleus of an atom. It carries a positive electric charge.

Refraction

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.