Medical Biophysics Lecture Notes

Flashcards generated from lecture notes on medical biophysics, covering key concepts and definitions.

Biophysics

Uses methods of physics to study biological processes.

Polymer

Large molecule made by connecting many smaller molecules.

Residue

Smaller molecules that make up polymers.

Biopolymers

Biological polymers where residues have something in common but are not identical.

Active Site

Particular part of a molecule involved in carrying out its function.

Conformational Transitions (Denaturation)

Change in shape; in biophysics, the 3D arrangement of atoms in a molecule.

DNA Melting

Unwinding of DNA molecule to replicate itself.

Intermolecular Binding

Binding together of molecules.

Ligand

Smaller molecule or atom that binds to a larger molecule.

Diffusion

Process of molecules spreading out due to random motion, moving from higher to lower concentration.

Molecular Transport

How molecules move around cells and outside to inside the cell.

Membrane

Limits and controls the movement of molecules into and out of the cell and from one region of the cell to another; able to create electrical potential.

Liposomes

Lipid vesicles for drug delivery systems.

Superhelix

Helix of a helix.

Supercoiling

Process of forming a superhelix in DNA (tertiary structure).

Quaternary Structure (DNA)

Occurs when DNA superhelix wraps around histone proteins.

Cell Motility

Self-induced movement of a cell.

Bioenergetics

Study of energy transduction in living cells; obeys the laws of thermodynamics.

Statistical Mechanics

How molecules move, their energy, and shape changes; calculates statistical probability of events.

Kinetics

Measuring the speed of biological processes.

Machine

Device that can alter the direction and/or size of a force.

Motor

Special type of machine that converts potential energy into mechanical energy (motion).

Michaelis-Menten Equation

Rate equation for one-substrate enzyme-catalyzed reaction.

Michaelis-Menten Model of Kinetics

Explains how the rate of an enzyme-catalyzed reaction depends on the concentration of the enzyme and its substrate.

Biomechanics

Motion of Animals

Excitable tissue

Cells that create or use electric impulses: nerve, muscle, sensory cell, and electrogenic and electroreceptive cells.

Sensory Biophysics

Electrophysiology and mechanics of the senses.

Preparative Technique

Purify or isolate biological specimens or get them ready for use in some other process or further experimentation

Analytical Technique

Used to measure physical aspects of a biological system

Superior (cranial)

Above; upper part (Head from abdomen)

Inferior (Caudal)

Below; lower part (Navel from chin)

Anterior (ventral)

In front; front of body (Breastbone and spine)

Posterior (dorsal)

Behind; back of body (Heart from breastbone)

Medial

Inner Side; midline of body (Heart to arm)

Lateral

Outer Side; away of midline (Arms from chest)

Intermediate

Bet. Medial and Lateral (Collarbone)

Supination

radius and ulna are parallel

Pronation

radius rotates over ulna

Kinematics

Describes motion using equations of motion; explains acceleration, velocity, and position of objects (mass not considered).

Linear Motion

Involves uniform motion of the system of interest, with all system parts moving in the same direction at the same speed.

Translational

Moves as a unit, and portions of the body do not move relative to each other (whole object moves)

Rectilinear

Straight line

Curvilinear

Curved line

Angular Motion

Rotation around an imaginary central line (axis of rotation) which is perpendicular to the plane in which the rotation occurs.

Inertia

resistance to action or to change.

Mass

quantity of matter composing a body.

Force

Push or pull acting on a body; characterized by magnitude, direction, and point of application.

Center of Gravity

Point around which the weight is equally balanced no matter how it is positioned.

Weight

Amount of gravitational force exerted on a body.

Pressure

Force distributed over a given area.

Volume

Amount of space that it occupies.

Density

Combines mass of body with volume of body; defined as mass per unit of volume.

Torque

Rotary force; the angular equivalent of linear force.

Impulse

When force is applied, the resulting motion depends on magnitude and duration of the force.

Allometry

Describes how the characteristics of living creatures change with size.

Compression/Compressive Force

Pressing or squeezing force directed axially through a body; shortens.

Tension/Tensile Force

Pulling or stretching force directed axially through a body; stretches.

Shear

Force directed to a parallel surface; tends to cause one portion of the object to slide or displaced to another portion of the object.

Mechanical Stress

The outcome of the action of forces on the human body is how the force is distributed.

Torsion

Structure is caused to twist about its longitudinal axis, typically when one end of the structure is fixed

Bending

Asymmetric loading that produces tension on one side of a body’s longitudinal axis and compression on the other side

Strain

The measure of the deformation of a material created by a load.