bio chem flashcards ap bio

Atom

The basic unit of a chemical element, made up of protons, neutrons, and electrons.

Proton

A positively charged particle found in the nucleus of an atom.

Neutron

A neutral particle found in the nucleus of an atom.

Electron

A negatively charged particle that orbits the nucleus of an atom.

Atomic Number

The number of protons in the nucleus of an atom, which defines the element.

Atomic Weight

The weighted average of the masses of an element's naturally occurring isotopes.

Isotope

Different versions of an element that have the same number of protons but a different number of neutrons.

Cation

A positively charged ion, which has lost one or more electrons.

Anion

A negatively charged ion, which has gained one or more electrons.

Electron Configuration

The arrangement of electrons in the orbitals of an atom.

Octet Rule

The principle that atoms prefer to have eight electrons in their outermost shell.

Covalent Bond

A chemical bond formed when two atoms share electrons.

Polar Covalent Bond

A type of covalent bond where electrons are shared unequally between two atoms.

Nonpolar Covalent Bond

A type of covalent bond where electrons are shared equally between two atoms.

Ionic Bond

A chemical bond formed through the complete transfer of electrons from one atom to another.

Hydrogen Bond

A weak bond formed between a hydrogen atom and an electronegative atom.

Polarity of Water

The condition in which water molecules have a partial positive charge on the hydrogen atoms and a partial negative charge on the oxygen atom.

Cohesion

The attraction between molecules of the same substance, such as water molecules.

Adhesion

The attraction between different substances, such as water molecules and other materials.

Hydrophilic

Substances that are attracted to water and can dissolve in it.

Hydrophobic

Substances that repel water and do not dissolve in it.

Heat Capacity of Water

The amount of energy required to raise the temperature of water.

Universal Solvent

A characteristic of water due to its ability to dissolve many substances.

Acid

A substance that increases the concentration of hydrogen ions in a solution.

Base

A substance that increases the concentration of hydroxide ions in a solution.

pH Scale

A logarithmic scale used to measure the acidity or alkalinity of a solution.

Buffer

A solution that resists changes in pH when small amounts of acid or base are added.

Macromolecule

A large molecule, typically formed by the polymerization of smaller subunits.

Carbohydrates

Organic compounds made up of sugar molecules, providing energy and structural support.

Lipids

Fatty acids and their derivatives, which are hydrophobic and play roles in energy storage and cell membranes.

Proteins

Large biomolecules consisting of one or more long chains of amino acid residues, essential for structure and function in organisms.

Nucleic Acids

Biomacromolecules that store and transmit genetic information, such as DNA and RNA.

Amino Acids

The building blocks of proteins, consisting of an amino group, a carboxyl group, and a side chain.

Triglyceride

A type of lipid made up of three fatty acids and glycerol, used for long-term energy storage.

Phosphate Group

A functional group consisting of phosphorus atom bonded to four oxygen atoms, important in energy transfer and nucleic acids.

Hydroxyl Group

A functional group consisting of an oxygen atom bonded to a hydrogen atom (-OH) that makes molecules polar.

Carboxyl Group

A functional group (-COOH) that acts as an acid by donating a hydrogen ion.

Methyl Group

A functional group (-CH3) that contributes to the hydrophobic nature of a molecule.

Disulfide Bridge

A strong covalent bond that forms between sulfur atoms in the R groups of cysteine amino acids.

Peptide Bond

The bond formed between amino acids during protein synthesis.

Gene

A segment of DNA that contains the instructions for building a specific protein.

RNA

Ribonucleic acid, a molecule that plays a key role in coding, decoding, regulating, and expressing genes.

DNA

Deoxyribonucleic acid, the molecule that carries the genetic instructions for life.

Antibodies

Proteins produced by the immune system to identify and neutralize foreign objects like bacteria and viruses.

Enzymes

Proteins that act as catalysts to accelerate chemical reactions in cells.

Starch

A polysaccharide carbohydrate that serves as a form of energy storage in plants.

Glycogen

A polysaccharide that serves as a form of energy storage in animals.

Cellulose

A polysaccharide that provides structural support in plant cell walls.

Primary Structure

The linear sequence of amino acids in a protein.

Secondary Structure

Local folded structures that form within a protein due to hydrogen bonding.

Tertiary Structure

The overall three-dimensional shape of a protein formed by interactions between its side chains.

Quaternary Structure

The structure formed when two or more polypeptide chains aggregate into one functional protein.

Electronegativity

The tendency of an atom to attract a bonding pair of electrons.

Hydrophilic Molecules

Molecules that are attracted to water and can interact with it.

Hydrophobic Molecules

Molecules that repel water and do not easily mix with it.

Valence Electrons

The electrons in the outermost shell of an atom that are involved in forming bonds.

Condensation Reaction

A chemical reaction where two molecules combine to form a larger molecule, releasing water.

Hydrolysis Reaction

A chemical reaction where water is used to break down a compound.

Functional Group

A specific group of atoms within a molecule that is responsible for certain properties or reactions.

Phosphodiester Bond

A covalent bond between the phosphate group of one nucleotide and the sugar of another, forming the backbone of nucleic acids.

Ionic Compound

A compound formed by the electrostatic attraction between oppositely charged ions.

Polar Molecule

A molecule with a net dipole moment due to the opposing charges from polar bonds.

Peptidoglycan

A polymer consisting of sugars and amino acids that form a structural component of bacterial cell walls.

Complex Lipid

Lipids that contain additional elements beyond carbon, hydrogen, and oxygen, often including phosphorus or nitrogen.

Signal Transduction

The process by which a chemical or physical signal is transmitted through a cell.

Extracellular Matrix

A collection of extracellular molecules secreted by cells that provides structural and biochemical support to the surrounding cells.

Endoplasmic Reticulum

An organelle that synthesizes proteins and lipids, comprising rough (with ribosomes) and smooth variants.

Golgi Apparatus

An organelle involved in the modification, sorting, and packaging of proteins and lipids.

Mitochondria

Organelles known as the powerhouses of the cell, where ATP (energy) production occurs.

Chloroplast

An organelle found in plants and photosynthetic algae that conducts photosynthesis.

Gene Expression

The process by which information from a gene is used to synthesize functional gene products, often proteins.

Evolutionary Biology

The study of the origin and descent of species over time.

Biochemical Pathway

A series of chemical reactions occurring within a cell.

Cell Membrane

The biological membrane that separates and protects the interior of all cells from the outside environment.

Electrochemical Gradient

A gradient that involves both a difference in charge and a difference in concentration across a membrane.

Homeostasis

The process by which living organisms regulate their internal environment to maintain stable, constant conditions.

Anabolic Pathway

A metabolic pathway that constructs molecules from smaller units.

Catabolic Pathway

A metabolic pathway that breaks down molecules into smaller units.

Apoptosis

Programmed cell death, a process that eliminates old cells, unnecessary cells, and unhealthy cells.

Endocytosis

The process by which cells internalize substances from the extracellular environment.

Exocytosis

The process by which cells expel materials in vesicles.

Ecosystem

A biological community of interacting organisms and their physical environment.

Biomes

Large geographic biotic units, each characterized by its own climate and vegetation.

Biodiversity

The variety and variability of life on Earth, encompassing the diversity of species, ecosystems, and genetic differences.