ASVAB General Science Practice Test 577909

Questions 5
Topics Endoskeleton, Mantle, Medulla, Minerals, Reflection

Study Guide

Endoskeleton

An endoskeleton (internal skeleton) is a charateristic of vertebrate animals, including humans.

Mantle

Mantle makes up 84% of the Earth's volume and has an average thickness of approximately 1,800 miles (2,900 km). It is dense, hot, and primarily solid although in places it behaves more like a viscous fluid as the plates of the upper mantle and crust gradually "float" along its circumference.

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.

Minerals

Small quantities of certain minerals like iron, calcium, magnesium, and salt are important for nutrition and health.

Reflection

The law of reflection specifies how waves, including light waves, bounce off of surfaces. Specifically, the angle of incidence of the approaching wave is equal to the angle of reflection of the reflected wave as measured from a line perpendicular (90°) to the surface.