TEAS Science cheat sheet

Main idea = the point the whole passage supports; details support it but cannot replace it.

Inference must follow necessarily from stated evidence; if it needs outside knowledge, it is not inference.

Chronological order signals: first, next, then, finally, dates, and time-of-day references.

Cause-effect signals: because, therefore, as a result, consequently, due to, leads to.

Comparison-contrast signals: however, whereas, similarly, unlike, in contrast, both.

Author's purpose options: inform, persuade, entertain, express, or instruct; tone is the attitude conveyed.

Bias cue words: always, never, everyone, clearly, obviously, and emotionally loaded adjectives.

A summary restates the main idea plus key supporting points in fewer words, without new opinion.

Percent change = (new - old) / old x 100; a positive result is an increase, negative is a decrease.

Part = percent x whole, rewritten as percent = part / whole and whole = part / percent.

Slope = (y2 - y1) / (x2 - x1); slope-intercept form is y = mx + b.

Order of operations: parentheses, exponents, multiply/divide left to right, add/subtract left to right.

Ratio a:b compares quantities; a proportion sets two ratios equal and is solved by cross-multiplying.

Mean = sum / count; median = middle value of ordered data; mode = most frequent value.

Area of circle = pi r squared; circumference = 2 pi r; area of triangle = one-half base times height.

Unit conversion: multiply by a fraction equal to 1 with the target unit on top so unwanted units cancel.

Cell theory: all living things are made of cells, cells arise from existing cells, and the cell is the basic unit of life.

Mitochondria produce ATP via cellular respiration; ribosomes assemble proteins; chloroplasts carry out photosynthesis.

Mitosis yields two identical diploid cells; meiosis yields four genetically varied haploid gametes.

DNA bases pair A-T and C-G; transcription makes mRNA from DNA, and translation builds protein at the ribosome.

Homeostasis is maintenance of stable internal conditions through feedback such as temperature and blood glucose regulation.

Newton's second law: force = mass x acceleration; acceleration rises with force and falls with mass.

Atomic number = protons; mass number = protons + neutrons; isotopes differ in neutrons only.

pH below 7 is acidic, 7 is neutral, above 7 is basic; each whole step is a tenfold change in hydrogen ion concentration.

A complete sentence needs a subject, a verb, and a complete thought; a fragment lacks one of these.

Comma splice joins two independent clauses with only a comma; fix with a period, semicolon, or conjunction.

Its = possessive; it's = it is. Their = possessive; there = place; they're = they are.

Subject and verb must agree in number; intervening prepositional phrases do not change the verb.

Active voice: subject performs the action; passive voice: subject receives it and often adds a by-phrase.

Apostrophes show possession (singular -'s, plural -s') and contractions, never plural nouns.

Colons introduce a list or explanation after an independent clause; semicolons join related independent clauses.

Parallel structure requires items in a series to share the same grammatical form, such as all verbs or all nouns.