General Biology Lecture Review

Comprehensive vocabulary flashcards generated directly from the biology lecture transcript, covering key scientific principles, chemical concepts, macromolecules, cellular organelles, and metabolic processes.

Biology

The study of living organisms and their interactions with one another.

Scientific Method

The basic process of making observations, forming logical hypotheses, testing them with experiments or observations, and forming a conclusion.

Scientific Hypothesis

A proposed explanation that leads to predictions that can be tested with additional observations or experiments.

Variable

Any part of an experiment that can vary or change during the experiment.

Control

A part of an experiment that contains all components but never varies or changes.

Scientific Theory

A concept that is broader in scope than a hypothesis and is supported by a large body of evidence.

Properties of Life

The nine characteristics of living organisms: order, sensitivity or response to the environment, reproduction, adaptation, growth and development, regulation, homeostasis, energy processing, and evolution.

Cellular Respiration

The metabolism of glucose to yield energy.

Photosynthesis

The production of glucose using light energy.

Taxonomic Hierarchy

The ranking of taxonomic groups from most inclusive to least inclusive: Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.

Domains of Life

The three domains of life: Bacteria, Archaea, and Eukarya.

Six Kingdoms of Life

The six kingdoms of life: Bacteria, Archaea, Plants, Animals, Fungi, and Protistas.

Prokaryote

A single-celled organism with no nucleus and no membrane-bound organelles, such as Bacteria and Archaea.

Eukaryote

An organism made of cell(s) that contain a nucleus and membrane-bound organelles.

Domain Eukarya

The domain comprising three multicellular kingdoms (Plantae, Fungi, and Animalia) and Protista (all other eukaryotic organisms that are not plants, animals, or fungi).

Element

A substance that cannot be broken down to other substances by chemical reactions.

Atom

The smallest unit of matter that still retains the properties of an element.

Neutron

A subatomic particle located in the atomic nucleus that has no electrical charge (neutral).

Proton

A subatomic particle located in the atomic nucleus with a positive charge ($+$).

Electron

A subatomic particle forming a cloud around the nucleus with a negative charge ($-$).

Atomic Number

The number of protons in an atom's nucleus.

Mass Number

The sum of protons plus neutrons in the nucleus of an atom.

Isotopes

Atoms of the same element that have the same number of protons, but differ in the number of neutrons.

Valence Shell

The outermost electron shell of an atom, which mostly determines its chemical behavior and reactivity.

Covalent Bond

A chemical bond formed by the sharing of a pair of valence electrons by two atoms.

Nonpolar Covalent Bond

A covalent bond in which atoms share electrons equally.

Polar Covalent Bond

A covalent bond in which one atom is more electronegative, causing atoms to share electrons unequally.

Cation

A positively charged ion.

Anion

A negatively charged ion.

Hydrogen Bond

A bond formed when a hydrogen atom covalently bonded to one electronegative atom is also attracted to another electronegative atom on a different molecule.

Cohesion

Water molecules staying close together linked to each other by hydrogen bonds.

Adhesion

The clinging of one substance to a different substance.

Hydrophilic

Having an affinity for water; characterized by polar covalent bonds and solubility in water.

Hydrophobic

Not having an affinity for water; characterized by nonpolar covalent bonds and non-dissolving nature in water.

Acid

A substance yielding a pH balance less than $7$.

Base

A substance yielding a pH balance greater than $7$.

Buffer

A substance that minimizes changes in concentrations of $H^+$ and $OH^-$ in a solution.

Functional Groups

The components of organic molecules most commonly involved in chemical reactions, giving each molecule its unique properties.

Polymer

A long molecule consisting of many similar building blocks.

Monomer

Small building-block molecules that make up polymers.

Dehydration Reaction

A chemical reaction where monomers bond together through the loss of a water molecule ($H_2O$), removing an $-OH$ group from one monomer and an $-H$ from another.

Hydrolysis

A chemical process that disassembles polymers into monomers by adding a water molecule ($H_2O$), attaching an $-OH$ to one monomer and an $-H$ to the other.

Monosaccharides

Simple sugars; the simplest carbohydrates.

Polysaccharides

Carbohydrate macromolecules; polymers composed of many sugar building blocks.

Glucose

The most common monosaccharide, with formula $C_6H_{12}O_6$.

Starch

A storage polysaccharide found in plants.

Cellulose

A structural polysaccharide that is a major component of the tough wall of plant cells.

Glycogen

A storage polysaccharide found in animals.

Chitin

A structural polysaccharide found in the exoskeleton of arthropods and cell walls of many fungi.

Fat (Triacylglycerol)

A lipid constructed from glycerol and $3$ fatty acids linked by dehydration reactions, releasing $3$ water molecules.

Saturated Fatty Acids

Fatty acids with the maximum number of hydrogen atoms possible and no double bonds, which are solid at room temperature.

Unsaturated Fatty Acids

Fatty acids containing $1$ or more double bonds, which are liquid at room temperature (oils).

Phospholipids

Lipids that serve as major constituents of cell membranes.

Amino Acid

An organic molecule containing carboxyl and amino groups, built from a set of $20$ amino acids to form proteins.

Polypeptide

Unbranched polymers built from amino acids joined by peptide bonds.

Protein

A biologically functional molecule consisting of one or more polypeptides twisted, folded, and coiled into a unique 3D shape.

Primary Structure

The unique, genetically determined sequence of amino acids in a protein.

Secondary Structure

Coils and folds in a polypeptide chain resulting from hydrogen bonding.

Tertiary Structure

The overall shape of a polypeptide determined by interactions among side chains (R-groups).

Quaternary Structure

The protein structure that results when a protein consists of more than $1$ polypeptide chain.

Denaturation

The loss of a protein’s native structure, rendering the denatured protein biologically inactive.

Nucleic Acids

Biological molecules made of nucleotide monomers that store and transmit genetic information.

Plasma Membrane

A selective barrier made of a double layer of phospholipids (phospholipid bilayer).

Cytoplasm

The area between the plasma membrane and the nuclear envelope, containing a gel-like cytosol.

Nucleus

An organelle in eukaryotic cells enclosed by a double membrane with pores that contains most of the cellular DNA.

Chromosomes

Discrete units into which DNA is organized within the nucleus.

Ribosomes

Complexes of ribosomal RNA (rRNA) and protein responsible for protein synthesis using information from DNA.

Mitochondria

Organelles that serve as sites of cellular respiration, using oxygen to generate ATP.

ATP

Adenosine Triphosphate, the fundamental unit of cellular energy.

Central Vacuole

A large organelle found in plants that holds organic compounds and water.

Chloroplasts

Organelles found in plants and algae that contain chlorophyll and carry out photosynthesis.

Endomembrane System

A cellular system consisting of the Endoplasmic Reticulum (ER), Golgi apparatus, and Lysosomes.

Rough ER

Endoplasmic reticulum studded with ribosomes that secretes glycoproteins, distributes transport vesicles, and acts as a membrane factory.

Smooth ER

Endoplasmic reticulum lacking ribosomes that synthesizes lipids, metabolizes carbohydrates, detoxifies drugs and poisons, and stores calcium ions ($Ca^{2+}$).

Golgi Apparatus

An organelle that modifies products of the ER, manufactures certain macromolecules, and sorts and packages materials into transport vesicles.

Lysosome

A membranous sac of enzymes found in animals that breaks down food, recycles cell parts, and digests biological macromolecules.

Centrosome

A microtubule-organizing center found in animal cells containing a pair of centrioles.

Cell Wall

An external structure in plant cells located outside the plasma membrane that provides structural support and shape.

Cytoskeleton

A network of fibers extending throughout the cytoplasm that organizes cell structures, anchors organelles, supports the cell, and maintains its shape.

Cilia and Flagella

Microtubule-containing extensions projecting from some cells whose beating movement is controlled by microtubules.

Extracellular Matrix (ECM)

An elaborate matrix covering animal cells that aids in cellular connections and activities.

Plasmodesmata

Channels perforating plant cell walls that allow water and small solutes to pass from cell to cell.