ASVAB General Science Practice Test 189384

Questions 5
Topics Base Units, Crust, Ecosystem, Filtering Air, Species Groups

Study Guide

Base Units
Measurement Base Unit Example
length / distance meter (m) km
mass gram (g) kg
volume liter (L) mL
volume (medical) cubic centimeter (cc) cc
time second (s), minute (min), hour (h) ms, min, h
temperature centigrade (°C) °C

Crust

The crust is the Earth's outermost layer and is divided into oceanic and continental types. Oceanic crust is 3 miles (5 km) to 6 miles (10 km) thick and is composed primarily of denser rock. Continental crust is 20 to 30 miles (30 to 50 km) thick and composed primarily of less dense rock. The crust makes up approximately one percent of the Earth's total volume.

Ecosystem

An ecosystem is a biological community of interacting organisms and their physical environment. This includes both the biotic (living) and abiotic (non-living).

Filtering Air

After air enters through the nose, it passes through the nasal cavity which filters, moistens, and warms it. Further filtering takes place in the pharynx, which also helps protect against infection, and then in the trachea which is just past the epiglottis, responsible for preventing food from entering the airway.

Species Groups

A population is a group of organisms of the same species who live in the same area at the same time. A community is a group of populations living and interacting with each other in an area.