ASVAB General Science Practice Test 402991

Questions 5
Topics Filtering Air, Frequency, Kingdom, Medulla, Phase Transition

Study Guide

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.

Frequency

The rate of vibration of sound is called frequency and is measured in hertz (Hz). One hertz is one repetition per second and sounds with high frequency have a higher pitch than sounds with lower frequency. Humans can hear sounds in the range of 20 Hz to 20 kHz.

Kingdom

Below domain, life is classified into six kingdoms: plants, animals, archaebacteria, eubacteria, and fungi. The last kingdom, protists, include all microscopic organisms that are not bacteria, animals, plants or fungi. (Archaebacteria and eubacteria are sometimes combined into a single kingdom, monera.)

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.

Phase Transition

A substance undergoes a phase transition when it moves from one state of matter to another, for example, when water freezes or boils.