Science Terms Flashcards
Absolute zero
Lowest temperature possible
0º Kelvin
Acid
a chemical substance that neutralizes alkalis, dissolves some metals, and turns litmus red; typically, a corrosive or sour-tasting liquid of this kind.
Acid rain
Rain made acidic due to high pollution in the rain
Adrenaline
a hormone secreted by the adrenal glands, especially in conditions of stress, increasing rates of blood circulation, breathing, and carbohydrate metabolism and preparing muscles for exertion.
Air mass
a body of air with horizontally uniform temperature, humidity, and pressure.
Algae
a simple, nonflowering, and typically aquatic plant of a large group that includes the seaweeds and many single-celled forms. Algae contain chlorophyll but lack true stems, roots, leaves, and vascular tissue.
Alkali
a chemical compound that neutralizes or effervesces with acids and turns litmus blue; typically, a caustic or corrosive substance of this kind such as lime or soda.
Alloy
a metal made by combining two or more metallic elements, especially to give greater strength or resistance to corrosion.
Alternating current
is a type of electrical current, in which the direction of the flow of electrons switches back and forth at regular intervals or cycles.
Amino acid
Amino acids are molecules that combine to form proteins
Anemia
A condition where the blood does not have the right amount of red blood cells and hemoglobin
Antibody
a blood protein produced in response to and counteracting a specific antigen. Antibodies combine chemically with substances which the body recognizes as alien, such as bacteria, viruses, and foreign substances in the blood.
Aorta
A major artery that carries oxygenated blood blood away from the heart
Artery
A larger blood vessel that carries oxygenated blood from heart to organs
Atmosphere
the envelope of gases surrounding the earth or another planet.
Atom
the basic unit of a chemical element.
Bacteria
a member of a large group of unicellular microorganisms which have cell walls but lack organelles and an organized nucleus, including some that can cause disease.
Barometer
an instrument measuring atmospheric pressure, used especially in forecasting the weather and determining altitude.
Bedrock
solid rock underlying loose deposits such as soil or alluvium.
Boiling point
the temperature at which a liquid boils and turns to vapor.
Calorie
a unit of energy equivalent to the heat energy needed to raise the temperature of 1 gram of water by 1 °C (now often defined as equal to 4.1868 joules).
