Biophysics Lecture One Flashcards

Flashcards on Biophysics, covering key concepts, experiments, and techniques discussed in the lecture.

Biophysics

An interdisciplinary science that uses the principles, theories, and methods of physics to study and understand biological systems.

Why study physical properties of biological molecules?

Provides a description of their structures at various levels, from the atomic level to large assemblies of subunits Also provides insight into how macromolecules form, their interactions, how they function and how we can exploit them.

Energy sources used to determine physical properties of macromolecules

Light, heat, radioactive particles, magnetic force (eg. NMR), and centrifugal force.

Questions addressed by Molecular Biophysics

How do atoms join to make DNA and proteins? How do proteins work? How are variations in genes and proteins expressed in disease occurrence, disease control, and drug design?

Applications of Biophysics

Elucidation of DNA structure, decoding human genes in the Human Genome Project, sequencing genes and their relationships in organisms, preparation of vaccines, development of tools for understanding diseases such as cancer, and creating tools for medical imaging technologies (PET scans, MRI, CT scans, and sonograms).

Applications of Biophysics (continued)

Explains how complex systems in our bodies work (brain, circulation, immune system), helps understand interactions between macromolecules (nucleic acids, proteins), and advancements in therapeutic techniques and devices (kidney dialysis, defibrillator, artificial heart valves).

Applications of Biophysics (continued)

Exploring bioenergy and bioelectricity as alternatives to petroleum and coal and addressing food security, climate change, water resources, and emerging diseases.

Central Dogma of Molecular Genetics

DNA -> Primary Transcript -> mRNA -> Protein

Macromolecules

Polymers present in a cell with molecular weights ranging from 10^4 to 10^12 Daltons, made up of proteins, glycoproteins, and nucleic acids, that determine a cell’s shape, size, and function.

Molecular Biologists Activities

Identification of genes and their location, investigation of structure and function of genes and gene products, performing molecular separations, locating the position and movement of macromolecules in the cell, modifying macromolecules for specific functions, and designing macromolecules for many purposes.

Molecular Biologists Activities

Identification of genes and their location, investigation of structure and function of genes and gene products, performing molecular separations, locating the position and movement of macromolecules in the cell, modifying macromolecules for specific functions, and designing macromolecules for many purposes.

Gel Electrophoresis

Separates different nucleic acids or proteins and provides evidence of DNA as the genetic material.

Radiotracer Techniques

Techniques using labeled (radioactive) tracers to detect tiny quantities of substances.

Nucleic Acid Hybridization

Combines electrophoresis and labeled probes to identify specific DNA or map and quantify transcripts; includes Southern blots, Northern blots, DNA fingerprinting, DNA sequencing, and restriction mapping.

Techniques for detecting protein and DNA-protein interactions

Combines electrophoresis and labeling with antibodies or radioactive material to detect protein and DNA-protein interactions; includes Western blotting, DNA Footprinting, Gel Mobility Shifts and Microscopy.

Griffith's Experiment (1928)

Laid the foundation for identification of DNA as genetic material through experiments with Streptococcus pneumoniae.

Avery, Macleod, McCarty Experiment (1944)

Demonstrated that the transformation of Streptococcus pneumoniae from avirulent Type II-R to virulent Type II-S is the result of the transfer of DNA from dead Type II-S organisms to live Type II-R organisms.

Hershey-Chase Experiment (1952)

Provided evidence that genes were made of DNA through experiments using bacteriophages and radioactive labeling.

DNA (Deoxyribonucleic Acid)

Double-stranded, contains deoxyribose sugar, and the base Thymine.

RNA (Ribonucleic Acid)

Usually single-stranded, contains ribose sugar, and the base Uracil.

Nucleoside

A nitrogenous base linked to a pentose sugar (ribose or deoxyribose).

Nucleotide

A nitrogenous base linked to a pentose sugar and one or more phosphate groups.