Name: protein mapping with 2d gel electrophoresis
Uploaded: 2023-04-30T06:31:06.000Z
Duration: 7 min 31 s
Channel: JoVE

K12 Standards

new-york-state-science-learning-standards

New York State Science Learning Standards

High School

Physical Science

HS. Structure and Properties of Matter

HS-PS1-10.

Two-Dimensional Gel Electrophoresis

electroforesis en gel bidimensional

Electroforesis en gel bidimensional (2DGE) es una técnica que puede resolver miles de biomoléculas de la mezcla. Esta técnica consiste en dos métodos de separación diferentes que han sido acoplados entre sí: la concentración isoeléctrica (IEF) y sodio dodecil sulfato poliacrilamida gel electroforesis (SDS-PAGE). Esto físicamente separa compuestos a través de dos ejes de un gel por sus puntos isoeléctricos (una propiedad electroquímica) y sus pesos moleculares.
El procedimiento en este video cubre los principales conceptos de 2DGE y un procedimiento general para la caracterización de la composición de una solución de proteína compleja. En la sección de aplicaciones, incluyendo la detección de biomarcadores para la iniciación de la enfermedad y tratamiento de pacientes y el estudio de las proteínas después de modificación postraduccional (PTM) de seguimiento del progreso, se muestran tres ejemplos de esta técnica.
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Bidimensional, o 2D, electroforesis en gel es una técnica que utiliza dos métodos de separación diferentes que pueden separar miles de proteínas de una mezcla única. Una de las técnicas, SDS-PAGE o sodio dodecil sulfato poliacrilamida gel electroforesis, puede separar completamente solo de mezclas complejas. Electroforesis 2D parejas SDS-PAGE a un segundo método, isoeléctrico centrado o IEF, que partiendo de puntos isoeléctricos se separa, lo que permite la resolución de potencialmente todas las proteínas en una célula lisado. Este video le mostrará que los principios de 2D gel de electroforesis, un procedimiento general y algunas de sus aplicaciones biomédicas.
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Electroforesis 2D comienza con IEF como la primera dimensión. Cada proteína tiene un valor de pH, llamado punto isoeléctrico o pI, donde la carga neta es cero. Cuando una proteína se somete a un campo eléctrico, se moverá hacia el electrodo con carga opuesta. Muestras de interés se cargan en el gradiente de pH inmovilizado, o IPG, tiras que han encajado anfolitos, moléculas que contienen grupos ácidos y básicos. Un campo eléctrico se aplica a la franja de gradiente de pH, haciendo que las proteínas que migran hasta alcanzar el valor de pH que empareja su pI, donde pierden su carga neta.
Antes de ejecutar la segunda dimensión, las proteínas incrustadas son tratadas con SDS, los desnaturalizantes y proporciona una carga negativa uniforme. Una vez completado, las tiras IPG se colocan en un gel de poliacrilamida. Un aplicado campo eléctrico atrae las proteínas hacia el ánodo, con proteínas más grandes moviéndose más lentamente a través del gel.
Una vez que se ha separado la mezcla de proteínas según peso molecular y el pI, se visualiza el mapa del proteoma con manchas, y proteínas de interés se identifican.
Ahora que hemos discutido los principios de la electroforesis en 2D, vamos un procedimiento de laboratorio típico.
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Antes de que el experimento se puede realizar, las proteínas deben solubilizadas en los medios de comunicación. Solubilización de la muestra se obtiene por la agregación de proteínas con una combinación de agentes caotrópico para interrumpir las interacciones de unión de hidrógeno, detergentes no iónicos para evitar la alteración de la carga de las proteínas, agentes reductores para romper los enlaces disulfuro y tampones. Para eliminar interferencias abundantes proteínas y otras moléculas, el material se extrae secuencialmente por centrifugación y la colección del precipitado resultante; seguido por el tratamiento con la endonucleasa, una enzima usada para consumir cualquier ADN que pueda interferir con el experimento.
Una vez que las proteínas han sido solubilizadas, IPG strips son preparados mediante enjuague con una solución de limpieza de la tira y dejar boca abajo para secar. Cada tira entonces se asigna a un número de titular de la tira. Una vez listos, el extracto celular se carga en las tiras en un movimiento lento, desplazamiento desde el negativo al extremo positivo. Con el propósito de rehidratación, papel secante húmedo se coloca en la parte superior del electrodo y debajo de las tiras de gel; las tiras IPG se alinean entonces en el instrumento IEF. Se aplica una corriente eléctrica de alta, y las proteínas comienzan a migrar.
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Después de la finalización de la primera dimensión, el gel de SDS-PAGE se prepara en un aparato de fundición. Las tiras IPG son tratadas por colocarlos cara en tampón de equilibrado que contienen SDS. La unidad de electroforesis es preparada con la adición de tampón de electroforesis. Las tiras IPG tratadas se recogen con unas pinzas, colocar sobre las placas de gel y sellados con la solución de agarosa de sellado. Una fuente de tensión aplica un campo eléctrico, que se celebra hasta que las proteínas más rápido-mudanza son 1 cm de la parte inferior del gel.
Después de la terminación de la electroforesis, las proteínas deben ser visualizadas. Tradicionalmente esto se realiza mediante tinción con nitrato de plata o azul de Coomassie. Proteínas de interés pueden transferidas desde el gel y analizadas por análisis de Western blot.
Un segundo enfoque de identificación consiste en la supresión de las proteínas del gel, digerir, que el análisis por espectrometría de masas.
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Ahora que hemos revisado un procedimiento, Veamos algunas de las aplicaciones para electroforesis en 2D.
Uno de los usos más comunes de esta técnica es la identificación de moléculas implicadas en la progresión y la iniciación de la enfermedad. Electroforesis 2D, juntada con la espectrometría de masas, pueden detectar la para arriba - o abajo-regulación de proteínas específicas en áreas enfermas con las sanas.
Además, electroforesis en 2D es útil siguiendo el progreso de la respuesta de pacientes a un fármaco terapéutico potencial. Pueden tomarse muestras de pacientes en diferentes puntos de tiempo después de la administración del tratamiento. De esta manera, electroforesis 2D, junto con Western blot o análisis de espectrometría de masas, puede detectar proteínas asociadas con respuestas negativas tales como inflamación; o la ausencia de proteínas en un estado aliviada.
Otro uso para electroforesis en 2D es en el estudio de la estructura de la proteína y la función después de modificación postraduccional o PTM, que son adiciones a proteínas después de su traducción de mRNA. PTM puede regular una variedad de funciones, incluyendo la proteína de señalización, expresión génica, o causar daño oxidativo. Electroforesis en 2D es sensible a las modificaciones tales como metilación o acetilación, lo cual puede causar un cambio en pI, así como el peso molecular.
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<div class="chapter_text" id="script_5">
Sólo ha visto video de Zeus en electroforesis en 2D. Este video describe los principios de la técnica, un procedimiento experimental típico y varias de sus aplicaciones en el campo de la biomedicina.
¡Gracias por ver!
</div>

Electroforesis en Gel bidimensional

Two-dimensional gel electrophoresis (2DGE) is a technique that can resolve thousands of biomolecules from a mixture. This technique involves two distinct ...

La electroforesis en gel bidimensional, o 2D, es una técnica que utiliza dos métodos de separación distintos que pueden separar miles de proteínas de una sola mezcla. Una de las técnicas, SDS-PAGE o electroforesis en gel de poliacrilamida con dodecil sulfato de sodio, no puede separar completamente las mezclas complejas por sí sola. La electroforesis en gel 2D acopla el SDS-PAGE a un segundo método, el enfoque isoeléctrico o IEF, que separa en función de puntos isoeléctricos, lo que permite la resolución de potencialmente todas las proteínas en un lisado celular. Este video mostrará los principios de la electroforesis en gel 2D, un procedimiento general y algunas de sus aplicaciones biomédicas.La electroforesis en gel 2D comienza con IEF como primera dimensión. Cada proteína tiene un valor de pH, llamado punto isoeléctrico o pI, donde la carga neta es cero. Cuando una proteína se somete a un campo eléctrico, se moverá hacia el electrodo con carga opuesta. Las muestras de interés se cargan en tiras de gradiente de pH inmovilizado, o IPG, que tienen anfolitos incrustados, moléculas que contienen grupos ácidos y básicos. A continuación, se aplica un campo eléctrico a la franja de gradiente de pH, lo que hace que las proteínas migren hasta que alcancen el valor de pH que coincida con su pI, donde pierden su carga neta.Antes de ejecutar la segunda dimensión, las proteínas incrustadas se tratan con SDS, desnaturalizándolas y proporcionando una carga negativa uniforme. Una vez completadas, las tiras de IPG se colocan sobre un gel de poliacrilamida. Un campo eléctrico aplicado atrae las proteínas hacia el ánodo, y las proteínas más grandes se mueven más lentamente a través del gel.Una vez que se ha separado la mezcla de proteínas según pI y peso molecular, se visualiza el mapa del proteoma mediante tinciones y se identifican las proteínas de interés.Ahora que hemos discutido los principios de la electroforesis en gel 2D, repasemos un procedimiento típico de laboratorio.Antes de que se pueda realizar el experimento, las proteínas deben solubilizarse en medios. La solubilización de la muestra se logra mediante la desagregación de proteínas con una combinación de agentes caotrópicos para interrumpir las interacciones de enlace de hidrógeno, detergentes no iónicos para evitar la alteración de la carga de las proteínas, agentes reductores para romper los enlaces disulfuro y tampones. Para eliminar las proteínas abundantes y otras moléculas que interfieren, el material se extrae secuencialmente por centrifugación y recolección de la pellets resultante; seguido de un tratamiento con endonucleasa, una enzima utilizada para consumir cualquier ADN que interfiera con el experimento.Una vez que las proteínas se han solubilizado, las tiras de IPG se preparan enjuagando con una solución limpiadora de tiras y se dejan secar boca abajo. A cada tira se le asigna un número de soporte de tira. Una vez listo, el extracto celular se carga en las tiras con un movimiento lento y deslizante desde el extremo negativo al positivo. Con el fin de rehidratar, se coloca papel secante húmedo encima del electrodo y debajo de las tiras de gel; A continuación, las tiras de IPG se alinean en el instrumento IEF. Se aplica una corriente eléctrica alta y las proteínas comienzan a migrar.Una vez completada la primera dimensión, el gel para SDS-PAGE se prepara en un aparato de fundición. Las tiras de IPG se tratan colocándolas boca abajo en un tampón de equilibrio que contiene SDS. La unidad de electroforesis se prepara con la adición de tampón de electroforesis. Las tiras de IPG tratadas se recogen con pinzas, se colocan encima de las placas de gel y se sellan con una solución selladora de agarosa. Luego, una fuente de voltaje aplica un campo eléctrico, que se mantiene hasta que las proteínas que se mueven más rápido están a 1 cm del fondo del gel.Una vez finalizada la electroforesis, se deben visualizar las proteínas. Tradicionalmente, esto se realiza teñiendo con azul de Coomassie o nitrato de plata. Las proteínas de interés pueden transferirse del gel y analizarse mediante análisis de Western blot.Un segundo enfoque de identificación implica la escisión de las proteínas del gel, digeriéndolas, y luego analizarlas mediante espectrometría de masas.Ahora que hemos revisado un procedimiento, veamos algunos de los usos de la electroforesis en gel 2D.Uno de los usos más comunes de esta técnica es la identificación de moléculas implicadas en el inicio y la progresión de la enfermedad. La electroforesis en gel 2D, junto con la espectrometría de masas, puede detectar la regulación positiva o negativa de proteínas específicas en áreas enfermas en comparación con las sanas.Además, la electroforesis en gel 2D es útil para seguir el progreso de la respuesta de los pacientes a un posible fármaco terapéutico. Se pueden tomar muestras de los pacientes en varios momentos después de la administración del tratamiento. De esta manera, la electroforesis en gel 2D junto con el Western blot o el análisis de espectrometría de masas, pueden detectar proteínas asociadas con respuestas negativas como la inflamación; o la ausencia de proteínas en un estado aliviado.Otro uso de la electroforesis en gel 2D es en el estudio de la estructura y función de las proteínas después de la modificación postraduccional, o PTM, que son adiciones a las proteínas después de su traducción desde el ARNm. Los PTM pueden regular una variedad de funciones, incluida la señalización de proteínas, la expresión génica o causar daño oxidativo. La electroforesis en gel 2D es sensible a modificaciones como la metilación o la acetilación, que pueden causar un cambio en el pI, así como en el peso molecular.Acabas de ver el vídeo de JoVE sobre la electroforesis en gel 2D. En este vídeo se describen los principios de la técnica, un procedimiento experimental típico, y varias de sus aplicaciones en el campo de la biomedicina.¡Gracias por mirar!

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protein mapping with 2d gel electrophoresis

Protein mapping with 2D gel electrophoresis separates complex protein mixtures across two steps. The method combines isoelectric focusing, or IEF, with sodium dodecyl sulfate polyacrylamide gel electrophoresis, or SDS-PAGE. Together, these methods can resolve thousands of biomolecules from a single sample by their isoelectric point and molecular weight.

The first dimension is IEF. Each protein has an isoelectric point, or pI, which is the pH where its net charge is zero. Proteins are loaded onto immobilized pH gradient, or IPG, strips that contain ampholytes, which are molecules with both acidic and basic groups. When an electric field is applied, the proteins move until they reach the pH that matches their pI. At that point, they stop moving because they no longer have a net charge.

Before the second dimension, the proteins are treated with SDS. This step denatures the proteins and gives them a uniform negative charge. The IPG strips are then placed on a polyacrylamide gel for SDS-PAGE. When the electric field is applied, proteins move toward the anode, and larger proteins move more slowly through the gel.

A typical lab workflow begins by solubilizing the protein sample. This is done with chaotropic agents, nonionic detergents, reducing agents, and buffers. The sample is then cleaned by sequential centrifugation and pellet collection, and endonuclease is used to remove DNA that could interfere with the experiment. IPG strips are rinsed, dried, numbered, and loaded with the extract in a slow motion from the negative end to the positive end. Damp blotting paper helps with rehydration before the strips are run on the IEF instrument.

After the first run, the SDS-PAGE gel is prepared in a casting apparatus. The IPG strips are placed face down in SDS-containing equilibration buffer, and then positioned on the gel plates with agarose-sealing solution. Electrophoresis continues until the fastest-moving proteins are about 1 cm from the bottom of the gel. The separated proteins are then visualized with stains such as Coomassie blue or silver nitrate. Proteins of interest can also be transferred for Western blot analysis or excised, digested, and identified by mass spectrometry.

2D gel electrophoresis is widely used in biomedicine. It can help identify proteins involved in disease initiation and progression by comparing diseased and healthy samples. It is also useful for tracking how patients respond to a potential therapeutic drug over time. Another application is the study of posttranslational modifications, or PTMs, which are changes made to proteins after translation from mRNA. Methylation and acetylation can shift both pI and molecular weight, making them detectable with this method.

Protein Mapping with 2D Gel Electrophoresis

protein-mapping-with-2d-gel-electrophoresis

dialysis: diffusion based separation

Dialysis for Buffer Exchange in Biochemistry

Dialysis is a common biochemistry technique for buffer exchange and desalting. It separates molecules by diffusion through a semipermeable membrane, which lets small molecules pass while holding larger biomolecules inside the sample. The membrane is the key part of the setup. Its pores create a molecular weight cutoff, so a membrane such as a 10 kDa membrane usually keeps molecules larger than 10 kilodaltons inside. This cutoff is not exact, because membranes have a range of pore sizes.

enzyme assays and kinetics

Measuring Enzyme Reaction Rates

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maldi-tof mass spectrometry

How MALDI-TOF Reads Biomolecules

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tandem mass spectrometry

Tandem Mass Spectrometry for Biomolecule Analysis

Tandem mass spectrometry is used to isolate a biomolecule and break it into smaller pieces so its makeup can be studied. Because biomolecules often have large, complex structures, it can be hard to identify their molecular composition and sequence from a single measurement. By linking mass spectrometers in series, the technique first selects one ion and then analyzes the fragments it produces. The process starts with an ion source that converts the sample into ions. A mass analyzer then...

protein crystallization

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chromatography-based biomolecule purification methods

chromatography-based-biomolecule-purification-methods

Protein Purification with SEC and IMAC

Protein purification with size-exclusion chromatography and affinity chromatography helps isolate biomolecules from complex mixtures. These methods are common in biochemistry because purified samples are needed before a biomolecule’s properties and activity can be studied. The video focuses on the principles behind size-exclusion chromatography, affinity chromatography, and immobilized metal affinity chromatography, or IMAC. Size-exclusion chromatography, or SEC, separates molecules by size. A...

two-dimensional gel electrophoresis

Protein mapping with 2D gel electrophoresis separates complex protein mixtures across two steps. The method combines isoelectric focusing, or IEF, with sodium dodecyl sulfate polyacrylamide gel electrophoresis, or SDS-PAGE. Together, these methods can resolve thousands of biomolecules from a single sample by their isoelectric point and molecular weight. The first dimension is IEF. Each protein has an isoelectric point, or pI, which is the pH where its net charge is zero. Proteins are loaded...

metabolic labeling

Tracking Cell Chemistry with Metabolic Labels

Metabolic labeling tracks cell chemistry by using chemical analogs that cells take up and build into biomolecules. These labels help scientists follow biochemical changes and modifications inside cells. The labeled products can then be studied with tools such as SDS-PAGE and NMR to learn more about metabolic pathways. Several labeling strategies are shown here. Isotopic labeling uses analogs that match the natural molecule but contain uncommon isotopes, such as carbon-13 and nitrogen-15 in an...

electrophoretic mobility shift assay (emsa)

electrophoretic-mobility-shift-assay-emsa

Detecting Protein-DNA Binding by EMSA

Electrophoretic mobility shift assay, or EMSA, is a biochemical method used to detect binding between proteins and nucleic acids. It is also called a gel shift assay. The test compares how a labeled nucleic acid moves through a gel before and after it binds a protein. EMSA is used to see whether a specific protein binds to a specific nucleic acid. First, the nucleic acid is labeled to make a probe. The transcript describes radioactive phosphorus-32 as a common label. The probe is then mixed...

photometric protein determination

Measuring Protein Concentration with Absorbance

Measuring protein concentration with absorbance is a key step in many biochemical assays. Photometric methods use the fact that samples with more light-absorbing material transmit less light. Because concentration and absorption are directly related, this makes it possible to measure an unknown sample. The core idea comes from the Beer-Lambert Law. This law states that the concentration of a light-absorbing species is proportional to its absorbance. The video also introduces the Bradford assay...

density gradient ultracentrifugation

Sucrose Gradient Separation in an Ultracentrifuge

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co-immunoprecipitation and pull-down assays

co-immunoprecipitation-and-pull-down-assays

Protein Interaction Capture Methods in Cells

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reconstitution of membrane proteins

Membrane Proteins in Liposome Models

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f&#246;rster resonance energy transfer (fret)

FRET as a Molecular Ruler in Cells

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surface plasmon resonance (spr)

SPR Biosensors for Tracking Binding Kinetics

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biochemistry

Esta colección presenta varios métodos de purificación comúnmente usados, como la cromatografía de afinidad y métodos analíticos, como MALDI-TOF. Además, los videos muestran métodos para evaluar la interacción y la función de diversas biomoléculas como en la coprecipitación y el etiquetado metabólico.

See how 2D gel electrophoresis separates proteins by pI and size, then use staining, Western blot, or mass spectrometry to identify biomarkers and PTMs.

Protein Mapping with 2D Gel Electrophoresis | JoVE K12

HS. Chemical Reactions

HS-PS1-11.

Life Science

Structure and Function

HS-LS1-1.

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Matter and Energy in Organisms and Ecosystems

HS-LS1-6.

Inheritance and Variation of Traits

HS-LS3-1.

Overview

Principles of 2D Gel Electrophoresis

Sample Preparation and Running Isoelectric Focusing

Running SDS-PAGE and Visualization/Analysis

Applications

Summary

Periodic Classification of the Elements

The periodic table arranges atoms based on increasing atomic number so that elements with the same chemical properties recur periodically. When their ...

atomic-radii-and-effective-nuclear-charge

Atomic Radii and Effective Nuclear Charge

The elements in groups of the periodic table exhibit similar chemical behavior. This similarity occurs because the members of a group have the same number ...

Ionic Radii

Ionic radius is the measure used to describe the size of an ion. A cation always has fewer electrons and the same number of protons as the parent atom; it ...

Ionization Energy

The amount of energy required to remove the most loosely bound electron from a gaseous atom in its ground state is called its first ionization energy ...

Electron Affinity

The electron affinity (EA) is the energy change for adding an electron to a gaseous atom to form an anion (negative ion).



This process can be either ...

Electron Orbital Model

Orbitals are the areas outside of the atomic nucleus where electrons are most likely to reside. They are characterized by different energy levels, shapes, ...

The Aufbau Principle and Hund's Rule

To determine the electron configuration for any particular atom, we can build the structures in the order of atomic numbers. Beginning with hydrogen, and ...

Coordination Chemistry Complexes

Source: Laboratory of Dr. Neal Abrams &#8212; SUNY College of Environmental Science and Forestry
Transition metals are found everywhere from vitamin ...

Use the periodic table as a model to predict the relative properties of elements based on the patterns of electrons in the outermost energy level of atoms.

HS-PS1-1.

Types of Chemical Bonds

Chemical bonding theories were pioneered by American chemist Gilbert&#xA0;N. Lewis. He developed a model called the Lewis model to explain the type and ...

Lewis Symbols and the Octet Rule

Chemical bonds are complex interactions between two or more atoms or ions, which reduce the potential energy of the molecule. Gilbert N. Lewis developed a ...

Ionic Bonding and Electron Transfer

Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence ...

The Born-Haber Cycle

Lattice Energy&#xA0;

An ionic compound is stable because of the electrostatic attraction between its positive and negative ions. The lattice energy of a ...

trends-in-lattice-energy-ion-size-and-charge

Trends in Lattice Energy: Ion Size and Charge

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Covalent Bonding and Lewis Structures

Compared to ionic bonds, which results from the transfer of electrons between metallic and nonmetallic atoms, covalent bonds result from the mutual ...

Electronegativity

Whether a bond is nonpolar or polar covalent is determined by a property of the bonding atoms called electronegativity.&#xA0;

Electronegativity values of ...

bond-polarity-dipole-moment-and-percent-ionic-character

Bond Polarity, Dipole Moment, and Percent Ionic Character

Bond Polarity

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lewis-structures-of-molecular-compounds-and-polyatomic-ions

Lewis Structures of Molecular Compounds and Polyatomic Ions

To draw Lewis structures for complicated molecules and molecular ions, it is helpful to follow a step-by-step procedure as outlined:


	Determine the ...

Resonance

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Formal Charges

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Exceptions to the Octet Rule

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	...

Bonding in Metals

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VSEPR Theory and the Basic Shapes

Overview of VSEPR Theory

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vsepr-theory-and-the-effect-of-lone-pairs

VSEPR Theory and the Effect of Lone Pairs

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Predicting Molecular Geometry

VSEPR Theory for Determination of Electron Pair Geometries

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Molecular Shape and Polarity

Dipole Moment of a Molecule

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Valence Bond Theory

Overview of Valence Bond Theory

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Hybridization of Atomic Orbitals I

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Hybridization of Atomic Orbitals II

sp3d and sp3d&nbsp;2 Hybridization

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Molecular Orbital Theory I

Overview of Molecular Orbital Theory

Molecular orbital theory describes the distribution of electrons in molecules in the same way as the distribution of ...

Molecular Orbital Theory II

Molecular Orbital Energy Diagrams

The relative energy levels of atomic and molecular orbitals are typically shown in a molecular orbital diagram. For a ...

Molecular Orbital (MO) Theory

Source: Tamara M. Powers, Department of Chemistry, Texas A&#38;M University
This protocol serves as a guide in the synthesis of two metal complexes ...

Intermolecular vs Intramolecular Forces

Intermolecular forces (IMF) are electrostatic attractions arising from charge-charge interactions between molecules. The strength of the intermolecular ...

Intermolecular Forces

Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions ...

Molecular and Ionic 
Solids

Crystalline solids are divided into four types: molecular, ionic, metallic, and covalent network based on the type of constituent units and their ...

comparing-intermolecular-forces-melting-point-boiling-point

Comparing Intermolecular Forces: Melting Point, Boiling Point, and Miscibility

Intermolecular forces are attractive forces that exist between molecules. They dictate several bulk properties, such as melting points, boiling points, ...

Plan and conduct an investigation to gather evidence to compare the structure of substances at the bulk scale to infer the strength of electrical forces between particles.

HS-PS1-3.

Radioactivity and Nuclear Equations

Nuclear chemistry is the study of reactions that involve changes in nuclear structure. The nucleus of an atom is composed of protons and, except for ...

Types of Radioactivity

The most common types of radioactivity are &#945; decay, &#946; decay, &#947; decay, neutron emission, and electron capture.
Alpha (&#945;) decay is the ...

Nuclear Stability

Protons and neutrons, collectively called nucleons, are packed together tightly in a nucleus. With a radius of about 10&#8722;15 meters, a nucleus is ...

Nuclear Binding Energy

The difference between the calculated and experimentally measured masses is known as the mass defect of the atom. In the case of helium-4, the mass defect ...

Radioactive Decay and Radiometric Dating

Radioactivity is a spontaneous disintegration of an unstable nuclide and is a random process, as all the nuclei in the sample do not decay simultaneously. ...

Nuclear Fission

Many heavier elements with smaller binding energies per nucleon can decompose into more stable elements that have intermediate mass numbers and larger ...

Nuclear Power

Controlled nuclear fission reactions are used to generate electricity. Any nuclear reactor that produces power via the fission of uranium or plutonium by ...

Nuclear Fusion

The process of converting very light nuclei into heavier nuclei is also accompanied by the conversion of mass into large amounts of energy, a process ...

Nuclear Transmutation

Nuclear transmutation is the conversion of one nuclide into another. It can occur by the radioactive decay of a nucleus, or the reaction of a nucleus with ...

Biological Effects of Radiation

All radioactive nuclides emit high-energy particles or electromagnetic waves. When this radiation encounters living cells, it can cause heating, break ...

determining-rate-laws-and-the-order-of-reaction

Determining Rate Laws and the Order of Reaction

Source: Laboratory of Dr. Neal Abrams &#8212; SUNY College of Environmental Science and Forestry
All chemical reactions have a specific rate defining the ...

Develop models to illustrate the changes in the composition of the nucleus of the atom and the energy released during the processes of fission, fusion, and radioactive decay.

HS-PS1-8.

Properties of Transition Metals

Transition metals are defined as those elements that have partially filled d orbitals. As shown in Figure 1, the d-block elements in groups 3&#8211;12 are ...

Coordination Compounds and Nomenclature

In most main group element compounds, the valence electrons of the isolated atoms combine to form chemical bonds that satisfy the octet rule. For ...

Metal-Ligand Bonds

The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain ...

Communicate scientific and technical information about why the particulate-level structure is important in the functioning of designed materials.

HS-PS2-6.

Protein Mapping with 2D Gel Electrophoresis

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