ASVAB General Science Practice Test 902331

Questions 5
Topics Biosphere, Circulation, Cytoplasm, Electron, Genetic Type

Study Guide

Biosphere

The biosphere is the global ecological system integrating all living beings and their relationships. This includes their interactions with the lithosphere (the rigid outer part of the earth, consisting of the crust and upper mantle), hydrosphere (all surface water), and atmosphere (the envelope of gases surrounding the planet).

Circulation

Like the respiratory system, the circulatory system serves to transport oxygen throughout the body while removing carbon dioxide. In addition, the circulatory system transports nutrients from the digestive system.

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

Electron

An electron is a subatomic particle that orbits the nucleus of an atom. It carries a negative electric charge. Generally, an atom has the same number of negative electrons orbiting the nucleus as it does positive protons inside.

Genetic Type

A person's genotype is their genetic makeup and includes both dominant and recessive alleles. Phenotype is how the genes express themselves in physical characteristics.