ASVAB General Science Practice Test 889851

Questions 5
Topics DNA, Fats, Light Waves, Medulla, Plate Tectonics

Study Guide

DNA

Deoxyribonucleic acid (DNA) is the molecule that contains genetic information. DNA is encoded through a combination of nucleotides that bind together in a specific double helix pattern.

Fats

Like carbohydrates, fats provide energy to the body. The difference is energy from fats tends to be longer burning as opposed to the quick fuel provided by carbohydrates. Fats come in three types, saturated (meats, shellfish, eggs, milk), monounsaturated (olives, almonds, avocados), and polyunsaturated (vegetable oils). Saturated fats can raise LDL ("bad") cholesterol while unsaturated fats can decrease it.

Light Waves

Unlike mechanical sound waves that require a physical medium for propagation, light waves are electromagnetic and can travel through empty space. Light waves are also much faster, travelling at 186,000 m/s vs. 343 m/s for sound waves.

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.

Plate Tectonics

The crust and the rigid lithosphere (upper mantle) is made up of approximately thirty separate plates. These plates more very slowly on the slightly more liquid mantle (asthenosphere) beneath them. This movement has resulted in continental drift which is the gradual movement of land masses across Earth's surface. Continental drift is a very slow process, occurring over hundreds of millions of years.