ASVAB General Science Practice Test 897573

Questions 5
Topics Breathing, Cytoplasm, Ecosystem, Heart, Phase Transition

Study Guide

Breathing

The diaphragm is a system of muscles that allows breathing. During inhalation, the diaphragm expands and air rushes in to fill the space created. Then, during exhalation, the diaphragm contracts and forces the air back out.

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

Ecosystem

An ecosystem is a biological community of interacting organisms and their physical environment. This includes both the biotic (living) and abiotic (non-living).

Heart

The heart is the organ that drives the circulatory system. In humans, it consists of four chambers with two that collect blood called atria and two that pump blood called ventricles. The heart's valves prevent blood pumped out of the ventricles from flowing back into the heart.

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.