BIO 5 Chapter 1 and Chapter 2 Study Guide Flashcards

Vocabulary flashcards covering core concepts, terminology, levels of biological organization, scientific inquiry, chemistry, and biological macromolecules from Chapter 1 and Chapter 2 study guides.

Metabolism

The sum of all chemical reactions and processes occurring within a living organism to maintain life.

Homeostasis

The ability of an organism or cell to maintain a stable internal environment despite changes in external conditions.

Natural Selection

The process through which living things respond to their environment and individuals with advantageous traits survive and reproduce, driving the evolution of a species.

Adaptive Traits

Heritable traits or characteristics that enhance an organism's survival and reproductive success in a specific environment.

Eukaryote

An organism whose cells contain a complex structure including a nucleus and membrane-bound organelles, belonging to one of the three domains of life.

Atom

The fundamental unit of matter that retains the chemical properties of an element, consisting of subatomic particles.

Molecule

A chemical structure composed of two or more atoms held together by chemical bonds.

Cell

The basic structural and functional unit of all living organisms.

Tissue

A group of similar cells working together to perform a specific function.

Organ

A structure composed of different tissue types that perform specific biological tasks within an organism.

Organ System

A group of organs that cooperate to carry out major physiological functions.

Organism

An individual living entity that demonstrates all seven characteristics of life.

Population

A group of individuals of the same species living in a specific geographical area.

Community

All the different biological populations that live and interact together in a common environment.

Ecosystem

A community of living organisms interacting with their non-living physical environment.

Biosphere

The global ecological system encompassing all regions of Earth inhabited by living things.

Science

A systematic approach to acquiring knowledge about the natural world through observation and empirical testing.

Scientific Method

A structured multi-step process used to investigate phenomena, consisting of observations, hypothesis formation, predictions, experimentation, and analysis.

Observations

Information gathered through direct perception or scientific instruments to initiate scientific inquiry.

Hypothesis

A tentative, testable explanation for a specific scientific observation or question.

Prediction

An expected outcome of an experiment formulated logically from a given hypothesis.

Variable

Any factor, condition, or parameter that can change or be controlled within an experiment.

Independent Variable

The factor in a scientific experiment that is intentionally changed or manipulated by the experimenter.

Dependent Variable

The factor in an experiment that is measured or observed to evaluate the effect of the independent variable.

Control Group

The baseline group in an experiment that does not receive the experimental treatment and is used for comparison.

Experimental Group

The group in an experiment that receives the independent variable or specific treatment being tested.

Confounding Variables

Uncontrolled factors that can unintentionally influence experimental outcomes and obscure accurate results or conclusions.

Statistical Significance

A mathematical determination that experimental findings are likely real and not due to random variation.

Theory

A well-substantiated explanation of a natural phenomenon supported by extensive evidence that evolves as new information arises.

Inductive Reasoning

A logical process where general principles are derived from a series of specific individual observations.

Deductive Reasoning

A logical process where specific predictions or conclusions are drawn from general principles or premises.

Phase I Clinical Trial

The first phase of clinical testing in humans, focused on assessing safety, dosage, and side effects in a small subject group.

Phase II Clinical Trial

The phase of human clinical trials designed to assess drug efficacy and safety in a moderate-sized patient group.

Phase III Clinical Trial

Large-scale testing in clinical trials to confirm drug effectiveness, track side effects, and compare with standard treatments.

Placebo

An inactive control substance given to participants in an experiment to isolate true physiological effects from psychological expectations.

Double-Blind Experiment

An experimental setup in which neither the test subjects nor the researchers know who receives the active treatment or placebo, minimizing bias.

Informed Consent

The process of voluntary agreement by a participant after being fully educated on the procedures, risks, and benefits of a study.

Epidemiological Studies

Studies that analyze health patterns and determinants in populations; useful for identifying correlations but limited in proving direct causation.

Matter

Anything that has mass and takes up space, existing in solid, liquid, or gas states.

Mass

The measure of the amount of matter in an object, quantified using standard mass units.

Weight

The force exerted on the mass of an object by a gravitational field.

Subatomic Particles

The constituent units of an atom—protons, neutrons, and electrons—characterized by their specific charges, masses, and arrangements.

Atomic Number

The value determined strictly by the number of protons in the nucleus of an atom.

Atomic Mass

The combined calculated weight of an atom's protons and neutrons.

Electron Shells

Energy levels around an atomic nucleus containing electrons, which determine the chemical properties and reactivity of an atom.

Compound

A substance formed from two or more different chemical elements combined in fixed proportions.

Molecular Formula

A chemical formula that indicates the exact types and quantities of atoms in a molecule.

Structural Formula

A visual representation showing the arrangement and chemical bonding of atoms in a molecule.

Covalent Bond

A chemical bond formed when two atoms share one, two, or three pairs of electrons (single, double, or triple covalent bonds).

Ion

An atom or group of atoms that has gained or lost one or more electrons, acquiring an electrical charge.

Ionic Bond

A chemical bond formed through electrostatic attraction between oppositely charged ions.

Polar Molecule

A molecule with an uneven distribution of electrical charge, distinguishing it from non-polar molecules with symmetrical charge distribution.

Hydrogen Bond

A weak attraction between a partially positive hydrogen atom in a polar molecule and an electronegative atom in another molecule.

Buffer

A chemical substance or system that helps minimize changes in pH when acids or bases are added.

Dehydration Synthesis Reaction

A chemical reaction that links monomers together into polymers by removing a molecule of water.

Hydrolysis Reaction

A chemical reaction that breaks polymers down into constituent monomers by adding a molecule of water.

Glycogen

A polysaccharide carbohydrate that functions as energy storage in animal tissues.

Starch

A polysaccharide carbohydrate synthesized by plants for energy storage.

Cellulose

A structural carbohydrate polymer found in plant cell walls.

Triglyceride

A lipid molecule composed of a single glycerol backbone attached to three fatty acid chains.

Phospholipid

A major cell membrane lipid consisting of a hydrophilic polar head and two hydrophobic fatty acid tails.

Steroids

A class of lipids characterized by a structure of four fused carbon rings, including cholesterol.

Cholesterol

A steroid lipid obtained from diet or synthesis that provides stability to animal cell membranes and acts as a biological precursor.

Primary Structure of Protein

The initial level of protein organization consisting of a linear sequence of amino acid monomers.

Secondary Structure of Protein

The localized coiling or folding patterns (such as alpha helices and beta sheets) held by hydrogen bonds in a polypeptide.

Tertiary Structure of Protein

The overall three-dimensional folding and structure of a single functional polypeptide chain.

Quaternary Structure of Protein

The protein level formed by the interaction and assembly of multiple polypeptide subunits.

Denaturation

A structural change in a protein that disrupts its natural three-dimensional shape, rendering it biologically non-functional.

Enzyme

A biological protein catalyst that increases the speed of specific chemical reactions without being permanently altered.

Active Site

The specific region of an enzyme where substrate molecules bind and undergo a reaction.

Enzyme-Substrate Complex

The temporary complex formed during a catalytic cycle, represented as $E + S \rightarrow ES \rightarrow E + P$.

Cofactor

A non-protein inorganic component or ion required by an enzyme for catalytic activity.

Coenzyme

An organic non-protein helper molecule (such as a vitamin derivative) necessary for enzyme function.

Nucleotide

The structural monomer of nucleic acids, consisting of a 5-carbon sugar, a phosphate group, and a nitrogenous base.

Adenosine Triphosphate (ATP)

A nucleotide-based molecule that acts as the primary energy currency for cellular functions.