Principles of Biophysics

These flashcards cover core concepts in biophysics, including systems, biomolecules, chemical interactions, water properties, stability, and biological processes essential for understanding the subject.

System

A group of interacting or interrelated entities that form a unified whole.

Open System

A system that can exchange both energy and matter with its surroundings.

Closed System

A system that can exchange only energy with its surroundings, not matter.

Isolated System

A system that cannot exchange either matter or energy with its surroundings.

Dynamic Equilibrium

A system that remains constant over time but requires continual work to maintain.

Biomolecules

Molecules present in organisms essential for biological processes.

Antioxidants

Molecules that inhibit or quench free radical reactions to delay cellular damage.

Covalent Bond

A chemical bond where two atoms share electrons.

Hydrogen Bond

An intermolecular force that is a type of dipole-dipole attraction involving hydrogen.

Hydrophobic Interactions

Relations between water and hydrophobes, or low water-soluble molecules.

Polarity of Water

Water is a polar molecule, making it an effective solvent.

Cohesion

Attraction between water molecules.

Adhesion

Attraction of water molecules to other substances.

Surfactants

Substances that reduce the surface tension of water.

Specific Heat of Water

Measure of heat required to raise the temperature of water.

Dielectric Constant

A measure of a substance's ability to reduce the electric force between charged particles.

Vapor Pressure

Pressure exerted by a vapor in equilibrium with its liquid.

Heat Capacity

The amount of heat required to change the temperature of a substance.

Freezing Point Depression

Decrease in the freezing point of a solvent when a solute is added.

Thermal Conductivity

The property of a material to conduct heat.

Electronegativity

A measure of an atom's ability to attract and hold onto electrons.

Ion-Dipole Interaction

Interaction between an ion and a polar molecule.

Ion Permeation

Process by which ions pass through a channel or membrane.

Hydration Shell

The layer of solvent molecules surrounding a solute particle.

Osmosis

Movement of water across a semipermeable membrane.

Macromolecules

Large molecules essential for life, including proteins, lipids, and nucleic acids.

Functional Groups

Specific groups of atoms within molecules that determine characteristics and chemical reactions.

Glycerol

A simple polyol compound and a key component of lipids.

Dimethyl Sulfoxide

A solvent with the ability to penetrate biological membranes.

Ethylene Glycol

A colorless, odorless, sweet-tasting organic compound used as an antifreeze.

Propylene Glycol

A synthetic organic compound used in food, cosmetics, and pharmaceuticals.

Molecular Interactions

Interactions that account for the association of atoms into molecules, ions, etc.

Cations

Positively charged ions.

Anions

Negatively charged ions.

Ionic Bond

A chemical bond formed between oppositely charged ions.

Van der Waals Forces

Weak attractions between molecules or parts of molecules that result from transient local partial charges.

Inductive Interactions

Interactions arising when external electric fields distort electron clouds.

Stable Equilibrium

A state where a system is stable over time without energy input.

Glutathione

An antioxidant present in cells that protects against oxidative stress.

Superoxide Dismutase (SOD)

An enzyme that catalyzes the dismutation of superoxide into oxygen and hydrogen peroxide.

Catalase (CAT)

An enzyme that converts hydrogen peroxide into water and oxygen.

Glutathione Peroxidase (GSHPx)

An enzyme that reduces peroxide levels in cellular environments.

Ecosystem

A biological community interacting with its environment.

Entropy

A measure of disorder or randomness in a system.

Redox Reactions

Chemical reactions involving the transfer of electrons.

Monosaccharides

The simplest form of carbohydrates, consisting of single sugar molecules.

Polysaccharides

Complex carbohydrates formed from long chains of monosaccharides.

Lipids

Biomolecules that are insoluble in water, including fats and oils.

Nucleic Acids

Biomolecules that are essential for storing and transmitting genetic information.

Photosynthesis

The process by which green plants convert light energy into chemical energy.

Cell Division

The process by which a parent cell divides into two or more daughter cells.

Morphogenesis

The biological process that causes an organism to develop its shape.

Dynamic Homeostasis

The ability of an organism to maintain stable internal conditions despite changes in the environment.

Electrolytes

Ionic substances that dissociate in solution to produce electrically conductive solutions.

Biochemical Pathways

Series of chemical reactions occurring within a cell.

Bioenergetics

The study of energy flow through living systems.

Cytosol

The aqueous component of the cytoplasm in which organelles are suspended.

Chemical Bonding

The joining of atoms to form new substances.

Transmembrane Proteins

Proteins that span the entire lipid bilayer of a cell membrane.

Genetic Drift

A mechanism of evolution involving random changes in allele frequencies.

Natural Selection

The process through which populations adapt to their environment through advantageous traits.

Biophysical Properties

Physical properties of biological systems that affect their behavior and function.

Cell Membrane

The protective barrier that encloses a cell and regulates internal conditions.

Nuclear Forces

Forces that hold protons and neutrons together in an atomic nucleus.

Life Cycle of Cells

The various stages a cell goes through from formation to division.

Metabolism

The set of life-sustaining chemical reactions in organisms.

Trophic Levels

The hierarchical levels in an ecosystem, determined by the flow of energy and nutrients.

Species Interactions

The ways in which species interact with each other, including predation, competition, and symbiosis.

Chemical Equilibrium

A state in which the concentrations of reactants and products remain constant over time.

Thermal Energy

The total kinetic energy of particles within a substance.

Activation Energy

The minimum energy required for a chemical reaction to occur.

Equilibrium Constant

A number that expresses the relationship between the concentrations of products and reactants at equilibrium.

Concentration Gradient

A difference in the concentration of a substance across a space.

Endothermic Reaction

A chemical reaction that absorbs heat from the surroundings.

Exothermic Reaction

A reaction that releases energy in the form of heat.

Phenotype

The observable characteristics of an organism resulting from the interaction of its genotype with the environment.

Genotype

The genetic constitution of an individual organism.

Catalyst

A substance that increases the rate of a chemical reaction without being consumed.

Chemical Energy

Energy stored in the bonds of chemical compounds.

Cellular Respiration

The process by which cells convert biochemical energy from nutrients into ATP.

Photosynthetic Pigments

Molecules that absorb light energy for photosynthesis.

Sustainability

The capacity to endure in a relatively constant fashion across multiple domains of life.

Homeostasis

The ability of a system to maintain internal stability.

Thermodynamic Laws

Principles that govern the behavior of energy and matter.

Biological Signaling

The process by which cells communicate with each other using chemical signals.

Gene Expression

The process by which the information from a gene is used to synthesize functional gene products.

Microenvironment

The small-scale environment surrounding a cell or organism.

Cellular Communication

The ways in which cells send and receive signals from each other.

Biochemical Engineering

The application of engineering principles to biological systems and processes.