ACT考试作为美国本科高端申请的重要考试，虽然不像托福那样属于“对英语的考试”(Test Of English)，只是“用英语的考试(Test in English)”但也需要长时间才能完成的耐力测试。这就要求考生要词汇的辨认有非常高的熟悉程度，最短的时间内对题目和阅读内容做出最快的判断。 下面就对ACT科学推理部分的词汇做一个整理汇编，方便大家复习。
Acceleration【物理】加速度— The rate that velocity changes per unit time and the direction it changes in. Computed from the change in velocity divided by tire change in time.
Common units are meters per second squared (m/s²)
acceleration due to gravity【物理】重力加速度— The acceleration of an object that is only acted on by the force of the Earth's gravity. This value is given the symbol g and near the surface of the Earth it has a value of approximately 9.8 m/s². The direction of the acceleration due to gravity is vertically downward.
Accuracy【数学】精确度— The closeness of an experimental measurement to the accepted or theoretical value.
Acid【化学】酸— A substance that is a proton donor. The pH of an acid is less than 7.
Analysis【interdisciplinary】分析— A stage in the scientific method where patterns of observations are made.
antioxidant【化学】抗氧化物— any substance that inhibits oxidation, including vitamin E, vitamin C, or beta carotene, and is thought to protect the body from the damaging effects of oxidation
aqueous solution【化学】水溶剂— A solution in which the solvent is water.
Arteries【生物】动脉— The vascular tissue which carries blood away from the heart.
Astronomy【天文】天文学— The study of planets, stars, and space.
Atom【物理】 原子— The smallest structure that has tire properties of an element. Atoms contain positively charged protons and uncharged neutrons in the nucleus. Negatively charged electrons orbit around the nucleus.
ATP—【生物】 三磷酸腺苷(Adenosine Triphosphate.)—A chemical that is considered to be the "fuel" or energy source for an organism.
Atria【生物】心房— The chambers of the heart that receive blood.
Base【化学】碱基— A substance that is a proton acceptor. The pH of a base is greater than 7.
Bacteria 【生物】细菌— one-celled organisms that are involved in fermentation, putrefaction, and infectious diseases.
Calibration【interdisciplinary】校准—The examination of the performance of an instrument in an experiment whose outcomes are known, for the purpose of accounting for the inaccuracies inherent in the instrument in future experiments whose outcomes are not known.
Capillaries【生物】毛细血管— Vascular tissue that receives blood from the arterioles and releases the blood to the venules.
Catalyst【化学】催化剂— An agent that changes the rate of a reaction, without itself being altered by the reaction.
celestial equator【天文】天体赤道— The extension of the Earth's equator out onto the celestial sphere.
celestial poles【天文】天极— Tire extension of the Earth's north and south pole onto the celestial sphere.
celestial sphere【天文】 天球— The imaginary sphere onto which all the stars are viewed as being on for the purposes of locating them.
cell membrane【生物】细胞膜— An organelle found in all cells that acts as the passageway through which materials can pass in and out. This organelle is highly selectively permeable, only allowing materials to pass through that it "chooses" chemically.
cell wall【生物】细胞壁— An organelle found primarily in plant cells and fungi cells, and also some bacteria. The cell wall is a strong structure that provides protection, support, and allows materials to pass in and out without being selectively permeable.
centripetal force【物理】 向心力— The net force that acts to result in the centripetal acceleration. It is not an individual force, but the sum of the forces in the radial direction. It is directed toward the center of the circular motion.
chemical change【化学】化学变化—A process that Involves the formation or breaking of chemical bonds.
Chromosome【生物】染色体— An organelle that contains the entire DNA of the organism.
Component【物理】分量，分向量— The part of a vector that lies in the horizontal or vertical direction.
Compound【化学】化合物— A substance composed of more than one element that has a definite composition and distinct physical and chemical properties.
Concentration【化学】浓度，浓缩— A measure of the amount of solute that is present in a solution. A solution that contains very little solute is called dilute. A solution that contains a relatively large amount of solute is said to be concentrated.