Unit 1: How Science Works, Biology Themes, and Basic Chemistry

Flashcards covering the fundamentals of the scientific method, biological themes, taxonomy, and basic chemistry including atomic structure and the properties of water.

What is the formal definition of science, and what is its linguistic origin?

Science is a systematic and logical approach to discovering how things work, derived from the Latin word "scientia", which translates to knowledge.

In scientific logic, how does an anecdote differ from scientific understanding?

An anecdote is an individual story or personal observation based on private experience and is not trustworthy, whereas scientific understanding is based strictly on large samples and average outcomes to draw accurate conclusions.

What is the core concept of inductive reasoning in science?

Inductive reasoning is an approach focused on observational science that seeks to find trends, patterns, and characteristics by collecting large amounts of data to form a general conclusion, rather than trying to prove or disprove a statement.

Define qualitative and quantitative data.

Qualitative data relates to observations using the five senses (appearance, texture, color), while quantitative data relies entirely on numerical values and exact measurements (weight, time, height).

What is the core concept of deductive reasoning?

Deductive reasoning is a hypothesis-based logic method that can be disproven but can never be fully proven.

What is a controlled experiment?

A scientific test designed to evaluate a hypothesis by changing only one variable at a time while keeping all other background conditions constant to ensure a fair test.

When and by whom was the scientific method first documented?

It was first documented by Sir Francis Bacon in the year $1500$.

What are the two core requirements for evidence in the scientific method?

1. Empirical Evidence (direct observation through experiments). 2. Measurable Evidence (data that can be counted or scaled using tools like a ruler or thermometer).

What two rules must a scientific hypothesis follow?

A hypothesis must be Testable (an experiment can be built around it) and Falsifiable (it is capable of being proven wrong).

What are the three distinct data outcomes in the scientific method used to formulate conclusions?

Outcome A: Data Disproves Hypothesis (must form a brand-new hypothesis); Outcome B: Data Is Inconclusive (must troubleshoot and rerun experiment); Outcome C: Data Supports Hypothesis (move forward to publish conclusions).

Define Independent, Dependent, and Controlled variables.

The Independent Variable is the one intentionally changed; the Dependent Variable is the measurable result or outcome; and Controlled Variables are constants that must remain unchanged for a fair test.

What is the primary difference between a scientific theory and a scientific law?

Theories are explanatory viewpoints that can never be fully proven (e.g., gravity as a push/pull force), while Laws are observations consistently proven using mathematical equations (e.g., $E=mc^2$) that describe a phenomenon without explaining why it happened.

Contrast the goals of Basic Science and Applied Science.

Basic Science seeks knowledge purely for understanding (e.g., mapping the human genome), while Applied Science uses that knowledge to develop technology or solve real-world problems (e.g., curing genetic diseases).

List the 8 functions of life required for an organism to be considered alive.

1. Highly Organized, 2. Respond to Stimuli, 3. Reproduction, 4. Adaptation, 5. Growth and Development, 6. Regulation, 7. Homeostasis, 8. Energy Processing.

What are the structural levels of biological organization starting from the smallest building block?

Atom $\rightarrow$ Molecule $\rightarrow$ Macromolecule $\rightarrow$ Organelle $\rightarrow$ Cell $\rightarrow$ Tissue $\rightarrow$ Organ $\rightarrow$ Organ System $\rightarrow$ Organism.

At which level does life officially begin?

The Cell.

Who is known as the "Father of Modern Taxonomy" and what problem did he solve?

Carl Linnaeus; he solved the confusion caused by common names by creating a universal system for classifying and naming living things.

What are the three strict formatting rules for Binomial Nomenclature?

1. Always capitalize the Genus. 2. Always keep the species lowercase. 3. Italicize when typing or underline when writing by hand.

Compare Prokaryotes and Eukaryotes regarding their nucleus and internal structure.

Prokaryotes have no nucleus and no membrane-bound organelles (simple); Eukaryotes have a distinct protective nucleus and specialized membrane-bound organelles (complex).

What are the Three Domains of Life identified by Carl Woese in $1977$?

1. Bacteria (Prokaryotic, unicellular, found everywhere); 2. Archaea (Prokaryotic, extremophiles); 3. Eukarya (Eukaryotic, includes four kingdoms).

What environment is required for organisms in the Kingdom Protista?

They require a wet or aquatic environment to survive (e.g., ponds, lakes, or wet tissues of a host).

What are the key features of the Kingdom Fungi?

They are decomposers, most are multicellular, and they have cell walls made of chitin.

Differentiate the cell walls of Plantae and Animalia.

Kingdom Plantae has cell walls made of cellulose, while Kingdom Animalia has no cell walls.

What subatomic particles make up an atom and what are their charges?

Proton (positive charge, in nucleus), Neutron (neutral charge, in nucleus), and Electron (negative charge, in shells).

In the periodic table, what do the rows and columns represent?

Rows (Periods) represent the number of electron shells (Rings); Columns (Groups) represent the number of valence electrons (Count).

What is the Octet Rule?

The tendency of atoms to be most stable when their outer shell is full, which for most elements means having $8$ valence electrons.

How does an Ionic Bond form?

It forms when one atom transfers electrons to another (usually a metal and nonmetal), resulting in a cation ($Na^+$) and an anion ($Cl^-$) that attract like magnets.

What is the difference between Polar and Nonpolar Covalent Bonds?

In Polar Covalent Bonds, electrons are shared unequally (e.g., $H_2O$), creating partial charges; in Nonpolar Covalent Bonds, electrons are shared equally (e.g., $CH_4$, $O_2$), leaving no charged ends.

Why does water have a high heat capacity?

Because it requires a vast amount of thermal energy to break the stubborn hydrogen bonds before the temperature of the water can actually change.

Why is the density of ice ecologically important?

Ice is less dense than liquid water and floats, acting as an insulating blanket that prevents bodies of water from freezing solid, which keeps aquatic ecosystems alive.

Define Cohesion and Adhesion in the context of water.

Cohesion is water molecules sticking to each other (creating surface tension); Adhesion is water molecules sticking to other polar surfaces (enabling capillary action in plants).

What is pH a direct measure of?

The Hydrogen ion ($H^+$) concentration in a liquid solution.

How much does the acidity change if a solution's pH moves from $7$ down to $5$?

The solution becomes $100$ times more acidic ($10 \times 10 = 100$) because the pH scale is logarithmic.

What is the strict homeostatic blood pH range for humans?

Between $7.2$ and $7.6$.

How do buffers maintain stable pH in the blood?

Buffers absorb excess $H^+$ ions when a solution is too acidic or release $H^+$ ions when it is too basic.

Which buffer system uses $CO_2$ to balance human blood pH?

The Carbonic Acid-Bicarbonate Buffer System ($H_2CO_3 \rightleftharpoons HCO_3^- + H^+$).