ACT prep

Acceleration

The rate of change of velocity

Acidic

Having a pH less than 7

Acute

(adj.) refers to an angle that is less than 90 degrees; (adj.) refers to a triangle with angles that are all less than 90 degrees; sharp; quick and precise; intense

Aerobic Respiration

The breakdown of glucose in the body of an animal to supply muscles with oxygen.

Aerosol

Solid or liquid particles suspended in gas

Alkalinity

Having a pH greater than 7 (contrast with acidic, which is having a pH less than 7).

Amino Acids

Various organic compounds that link together to form proteins.

Anatomical

Related to the structure of an organism

Antigen

A substance such as a toxin or enzyme capable of eliciting an immune response.

Antitoxin

An antibody created for and capable of neneutralizing a toxin

Bacteria

Single-celled microorganisms

Basalt

Solidified lava; a dense, gray, fine-grained igneous rock

Biomass

Total mass of all the living matter within a given area

Biosynthesis

The production of a chemical compound within the body

Boiling Point

The temperature a liquid must be to change states from liquid to gas

Capillary

A very slim tube; one of a network of extremely small blood vessels

Carbohydrate

Sugars and starches that serve as a major energy source for animals

Catalyst

An agent that causes or speeds up a chemical reaction

Celsius

A temperature scale in which the freezing point of water is 0 degrees and the boiling point is 100 degrees under normal atmospheric conditions

Cerebral Edema

Brain swelling

Chlorophyll

A green pigment produced in response to sunlight during photosynthesis.

Cholesterol

A soft, waxy compound found in the body and in the food we eat.

Collinear

23 of 450

Collinear

Passing through or lying on the same straight line.

Comet

A celestial body, having an elongated, curved vapor tail, which is seen only in that part of its orbit that is relatively close to the sun

Common Difference

The equal distance between one number in an arithmetic sequence and the next (for example, the common difference between 4, 6, and 8 is 2.).

Common Ratio

The ratio of one term and the next in a geometric sequence (for example, the common ratio between 2, 4, and 8 is 4/2 and 8/4, or 2.)

Compressibility

The ease with which pressure can alter the volume of matter

Congruent

Equal in length or measure

Cos

Abbreviation of cosine

Cosine

The ratio of the adjacent side (with respect to the angle of reference) to the hypotenuse in a right triangle

Cube

A term raised to the third power; a regular solid having six congruent faces

Cubic Inch

The volume of a cube with edges that all measure one inch.

Cylindrical

Having the shape of a cylinder, or a solid with circular ends and straight sides

Diagonal

A line segment joining two nonadjacent vertices of a polygon or solid (polyhedron).

Dilute

To weaken the strength of a solution

Directly Proportional

Increasing or decreasing together or with the same ratio

Ecology

The field of science that concentrates on relationships between organisms and their environments

Emissions

Things that are discharged (often gases into the air).

Emit

To release particles such as light, heat, or gases.

Epicanthic Fold

A fold of skin of the upper eyelid that only partly covers the eye's inner corner

Equilibrium

A state of balance

Erosion

The wearing away of an object by outside forces, like wind or water

Evaporate

To draw away moisture and convert into vapor

Experimental Variables

Elements of an experiment that are changed (distinguished from the constant, which is held the same in order to produce significant results).

Fahrenheit

A temperature scale in which the freezing point of water is 32 degrees and the boiling point is 212 degrees under normal atmospheric conditions

Fermentation

The chemical process of breaking down an organic substance into simpler substances such as the fermentation of sugar to alcohol

Friction

The force resistant to motion

Galvanism

A direct electrical current produced by chemical reactions

Gas

A fluid (such as air) that is not independent in shape or volume but tends to expand

Gas Chromatograph

A device used to detect the composition of an unknown material

Gastric Emptying

The movement of the stomach's contents from the stomach to the small intestine, and finally into the colon

Gravity

The force of attraction between two bodies of mass

Herbivorous

A plant-eating organism

Hydrogen Bonding

The chemical bonding of a hydrogen atom with another electronegative atom.

Hypotenuse

The longest side of a right triangle, which is always the side opposite the right (90°) angle.

Igneous Rock

Rock that is formed by the cooling and solidification of molten magma

Ignition Temperature

The temperature that a fuel must reach before combustion can begin

Infrared

Light energy having a wavelength greater the visible range; it is experienced as heat.

Interior Angle

An angle inside of a shape (that is, all of the interior angles in a triangle have a sum of 180 degrees).

Intracellular

Within a cell or cells

Isosceles Triangle

A triangle with two congruent sides and two congruent angles

Isotopes

Two or more atoms with an identical atomic number and differing in number of neutrons.

Kelvin

A temperature scale in which absolute zero is 0 degrees K, the freezing point of water is 273 degrees K, and the boiling point of water is 373 degrees K

Law of Sines

The relationship within a triangle of the sine of angles and the lengths of sides of a triangle.

Least Common Denominator (LCD)

The smallest number (other than 0) that is a multiple of a set of denominators (for example, the LCD of 14and16

1

4

and

1

6

is 12).

Least Common Multiple (LCM)

The smallest number that is a multiple of a set of numbers (for example, the LCM of 6 and 9 is 18).

Linear

Relating to a line

Lipid

An oily/waxy organic compound that cannot be dissolved in water

Liquid

a substance that is neither a solid nor a gas; (adj.) flowing

Lithosphere

The outer part of the Earth that includes the crust and upper mantle.

Log

Abbreviation of logarithm. Logarithms are used to indicate exponents of certain numbers called bases. By definition, logab=c if ac=b (for example, logx36=2 if x2=36. In this case, x=6.)

Macrophages

Protective cells

Manometer

A device that measures the pressure of liquids and gases.

Matrix

Rows and columns of elements arranged in a rectangle

Mean (also Arithmetic Mean)

average; found by adding all the terms in a set and dividing by the number of terms

Median

The middle value in a set of ordered numbers.

If the set of numbers is even, it is the average (mean) of the two middle values.

Melting Point

The temperature at which a solid softens into a liquid.

Mesosphere

A layer of the atmosphere fifty to eighty kilometers above the Earth's surface.

Metamorphism

The process of altering solid rock by changing its temperature, pressure, and chemistry.

Microorganism

An organism of microscopic or very small size.

Midpoint

The point that divides a line segment into two equal segments.

Mole

A unit of measurement for the molecular weight of a substance.

Molecular Weight

The weight of all of the atoms in a molecule.

Nanometer

One billionth of a meter.

Newton

The amount of force needed to accelerate a one-kilogram mass at a rate of one meter per second, per second.

Obtuse

An angle with a measure greater than 90 degrees but less than 180 degrees

Organic Matter

Matter that is derived from living organisms.

Organism

A living thing, either plant or animal.

Parallel

Lines in the same plane that do not intersect each other; in a coordinate plane, noncollinear lines or segments having the same slope as one another.