ASVAB General Science Practice Test 31215

Questions 5
Topics Cambrian Period, Consumers, Cytoplasm, DNA, Kinetic Energy

Study Guide

Cambrian Period

The Cambrian period is one of the most significant geological time periods. Lasting about 53 million years, it marked a dramatic burst of changes in life on Earth known as the Cambrian Explosion. It is from this period that the majority of the history of life on Earth, as documented by fossils, is found. Called the fossil record, the layering of these mineralized imprints of organisms preserved in sedementary rock have allowed geologists to build a historical record of plant and animal life on Earth.

Consumers

Most animals consume other organisms to survive. Consumers (heterotrophs) are divided into three types, primary, secondary, and tertiary, based on their place in the food chain.

Cytoplasm

The nucleus of a eukaryotic cell contains the genetic material of the cell and is surrounded by cytoplasm which contains many organelles. These include:

Organelle Function
ribosomes produce proteins
mitochondria produce energy
endoplasmic reticulum helps synthesize proteins and fats
Golgi apparatus prepare proteins for use
lysosomes help the cell manage waste
centrosomes guide cell reproduction

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.

Kinetic Energy

Kinetic energy is the energy posessed by a moving object. Potential energy is stored energy in a stationary object based on its location, position, shape, or state.