Name: hydrogen bonding and dna stability
Uploaded: 2025-05-22T09:05:54.000Z
Duration: 1 min 4 s
Channel: JoVE

K12 Standards

Florida Department of Education

High School

Physical Science

SC.912.P.8

SC.912.P.8.6

Hydrogen Bonds

Un enlace de hidrógeno es una atracción electrostática intermolecular entre un átomo de hidrógeno y un átomo electronegativo con un par solitario de electrones.
En una molécula polar, como el fluoruro de hidrógeno o HF, el amoníaco o NH3 y el agua oH2O, el átomo de flúor, nitrógeno u oxígeno es más electronegativo que el hidrógeno.
El átomo más electronegativo atrae los pares de electrones de enlace con más fuerza que el hidrógeno. Esto da como resultado una distribución desigual de electrones en el enlace, lo que le da al átomo electronegativo una carga negativa parcial y al átomo de hidrógeno una carga positiva parcial.
La carga positiva parcial en el átomo de hidrógeno le permite atraer pares de electrones no enlazados de un átomo electronegativo en su vecindad, formando un enlace de hidrógeno.
Los enlaces de hidrógeno proporcionan estabilidad estructural a varias moléculas biológicas, incluido el ADN.

enlaces de hidrógeno

Un enlace de hidrógeno se forma cuando un átomo de hidrógeno débilmente positivo ya enlazado a un átomo electronegativo (por ejemplo, el oxígeno en la molécula de agua) es atraído hacia otro átomo electronegativo de otra molécula polar, como el agua (H2O), el fluoruro de hidrógeno (HF) o el amoníaco (NH3). La gran diferencia de electronegatividad entre el átomo de H (2.1) y el átomo al cual está enlazado (4.0 para un átomo de F, 3.5 para un átomo de O o 3.0 para un átomo de N), combinado con el tamaño muy pequeño de un átomo de H, resulta en una distribución desigual de cargas entre el átomo de hidrógeno y el átomo electronegativo. Esto hace que el átomo de hidrógeno se vuelva parcialmente positivo y el átomo electronegativo se vuelva parcialmente negativo. Así, las moléculas con grupos F-H, O-H o N-H son fuertemente atraídas por grupos similares de moléculas cercanas y forman una atracción dipolo-dipolo particularmente fuerte llamada enlace de hidrógeno.

Los enlaces de hidrógeno tienen un efecto pronunciado en las propiedades de líquidos y sólidos. Por ejemplo, el punto de fusión y el punto de ebullición de la metilamina (CH3NH2) son mayores que los del etano (CH3CH3), aunque ambos son similares en tamaño y masa. A diferencia del etano, la metilamina posee un grupo −NH que le permite formar enlaces de hidrógeno e incrementar las fuerzas intermoleculares entre moléculas, eventualmente elevando su punto de fusión y ebullición.

El enlace de hidrógeno es común en el mundo natural, como el ADN que contiene información genética y se encuentra en todo organismo. Cada par de bases del ADN se forma mediante enlaces de hidrógeno a través de tres enlaces de hidrógeno. Esta complementariedad en el emparejamiento de bases contribuye a la forma y estabilidad de la estructura en doble hélice del ADN.



Este texto es adaptado de <a href="https://openstax.org/books/anatomy-and-physiology-2e/pages/">Openstax, Anatomy and Physiology 2e, Section 2.2: Chemical Bonds</a> and <a href="https://openstax.org/books/anatomy-and-physiology-2e/pages/">Openstax, Chemistry 2e, Section 10.1: Intermolecular Forces </a>

Enlaces de hidrógeno

Un enlace de hidrógeno se forma cuando un átomo de hidrógeno débilmente positivo ya está unido a un átomo electronegativo (por ejemplo, el oxígeno en la molécula de agua) ...

Education

Educación

JoVE Core

Anatomy and Physiology

Anatomía y Fisiología

Unit 1

Unidad 1

Fundamentals of Chemistry

Fundamentos de Química

KEY TERMS AND CONCEPTS

TÉRMINOS Y CONCEPTOS CLAVE

hydrogen bonding and dna stability

Hydrogen bonding helps explain why some molecules stick together more strongly than others. A hydrogen bond forms when a weakly positive hydrogen atom, already bonded to an electronegative atom, is attracted to another electronegative atom on a nearby polar molecule. Common examples include water, hydrogen fluoride, and ammonia.

This attraction happens because hydrogen has a much lower electronegativity than atoms such as fluorine, oxygen, and nitrogen. The electronegativity difference, along with hydrogen’s very small size, creates an uneven charge. The hydrogen becomes partially positive, and the electronegative atom becomes partially negative. Molecules with F-H, O-H, or N-H groups can then form a strong dipole-dipole attraction called a hydrogen bond.

Hydrogen bonding can change the properties of liquids and solids. For example, methylamine has a higher melting point and boiling point than ethane, even though the two molecules are similar in size and mass. The difference is that methylamine has an -NH group, which lets it form hydrogen bonds and strengthens the intermolecular forces between its molecules.

Hydrogen bonds are also important in living things. DNA, which carries genetic information in every organism, relies on hydrogen bonding between base pairs. Each base pair is held together by three hydrogen bonds. This complementary pairing helps give DNA its double helix shape and supports its stability.

Hydrogen Bonding and DNA Stability

what is matter?

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Matter is the substance that makes up the universe, from a grain of sand to a star. Scientists define matter as anything that occupies space and has mass. Mass is the amount of matter in an object, while weight depends on gravity. Mass stays the same whether an object is on Earth or in the zero-gravity environment of outer space. Weight changes when gravity changes. An object weighs more where gravity is stronger and less where gravity is weaker. A piece of cheese that weighs a pound on Earth...

the periodic table and organismal elements

the-periodic-table-and-organismal-elements

Organismal Elements in the Periodic Table

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atomic structure

From Atomos to the Modern Atom

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chemical symbols

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atomic number and mass number

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atomic weight

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isotopes and radioisotopes

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introduction to chemical bonds

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ionic bonds

Ionic Bonds and Charge Transfer

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covalent bonds

Polar and Nonpolar Covalent Bonds

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hydrogen bonds

Hydrogen bonding helps explain why some molecules stick together more strongly than others. A hydrogen bond forms when a weakly positive hydrogen atom, already bonded to an electronegative atom, is attracted to another electronegative atom on a nearby polar molecule. Common examples include water, hydrogen fluoride, and ammonia. This attraction happens because hydrogen has a much lower electronegativity than atoms such as fluorine, oxygen, and nitrogen. The electronegativity difference, along...

ions, molecules, and compounds

Atomic Charges, Bonds, and Compounds

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states of matter

Solids, Liquids, Gases, and Plasma

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colloids and suspensions

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types of chemical reactions: anabolic and catabolic

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types of chemical reactions: exchange and reversible

types-of-chemical-reactions-exchange-and-reversible

Electron Transfer and Chemical Equilibrium

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Chemical Energy and Reaction Types

Chemical reactions depend on energy transfer, chemical bonds, and the way matter collides. A reaction needs enough energy for particles to meet with the right force and precision. That energy can break old bonds and help form new ones. Kinetic energy is the energy of motion. A person lifting a brick uses kinetic energy to move the brick into place on a wall. Once the wall is built, it stores potential energy, which is the energy of position or structure. If the wall falls, that stored energy...

factors influencing the rate of chemical reactions

factors-influencing-the-rate-of-chemical-reactions

Chemical Reaction Rates and Catalysts

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Acids, bases, and pH help control how cells and body systems work. In biology, pH can strongly affect enzymes, proteins, and nucleic acids. Enzymes work best within a certain pH range, and pH changes can alter their structure or denature them, which changes how they function. Acids release hydrogen ions, or H+, in solution. A hydrogen ion is a proton, so it is very reactive in chemical reactions. Strong acids release all of their H+ in water and ionize completely. Hydrochloric acid (HCl) is a...

key terms and concepts

Learn how hydrogen bonding forms, why it strengthens intermolecular forces, and how it helps raise boiling points and stabilize DNA.

Hydrogen Bonding and DNA Stability | JoVE K12

anatomy and physiology

JoVE Core Anatomy and Physiology showcases the anatomical and physiological details of the human body in comprehensive, clear, and engaging video animations. This collection of lessons focuses on the structures, components, functions, and requirements of the human body. It is complemented by scientist-in-action videos that demonstrate the application of this knowledge in real-world medical and research settings.

Classifying Matter by State

Chemistry is the study of matter and the changes it undergoes. Matter is anything that has mass and occupies space. Matter is all around us; the air, ...

States of Matter

Solids, liquids, and gases are the three states of matter commonly found on Earth. A solid is rigid and possesses a definite shape. A liquid flows and ...

States of Matter and Phase Changes

The internal energy of a substance&#8212;the total kinetic energy of all its molecules and the potential energy of their associated forces&#8212;depends ...

molecular-comparison-of-gases-liquids-and-solids

Molecular Comparison of Gases, Liquids, and Solids

Particles in a solid are tightly packed together (fixed shape) and often arranged in a regular pattern; in a liquid, they are close together with no ...

Differentiate between physical and chemical properties and physical and chemical changes of matter.

SC.912.P.8.1

physical-and-chemical-properties-of-matter

Physical and Chemical Properties of Matter

The characteristics that enable us to distinguish one substance from another are called properties.

Physical Properties of Matter

A physical property is ...

Phase Transitions

Whether solid, liquid, or gas, a substance&#39;s state depends on the order and arrangement of its particles (atoms, molecules, or ions). Particles in the ...

phase-transitions-vaporization-and-condensation

Phase Transitions: Vaporization and Condensation

The physical form of a substance changes on changing its temperature. For example, raising the temperature of a liquid causes the liquid to vaporize ...

Vapor Pressure

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Clausius-Clapeyron Equation

The equilibrium between a liquid and its vapor depends on the temperature of the system; a rise in temperature causes a corresponding rise in the vapor ...

Phase Transitions: Melting and Freezing

Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy ...

phase-transitions-sublimation-and-deposition

Phase Transitions: Sublimation and Deposition

Some solids can transition directly into the gaseous state, bypassing the liquid state, via a process known as sublimation. At room temperature and ...

Heating and Cooling Curves

When a substance&#8212;isolated from its environment&#8212;is subjected to heat changes, corresponding changes in temperature and phase of the substance ...

Phase Diagrams

A phase diagram combines plots of pressure versus temperature for the liquid-gas, solid-liquid, and solid-gas phase-transition equilibria of a substance. ...

SC.912.P.8.2

The Atomic Theory of Matter

The earliest recorded discussion of the basic structure of matter comes from ancient Greek philosophers. Leucippus and Democritus argued that all matter ...

Subatomic Particles

Dalton was only partially correct about the particles that make up matter. All matter is composed of atoms, and atoms are composed of three smaller ...

The Wave Nature of Light

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The Electromagnetic Spectrum

The electromagnetic spectrum consists of all the types of electromagnetic radiation arranged according to their frequency and wavelength. Each of the ...

Interference and Diffraction

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Photoelectric Effect

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The Bohr Model

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Emission Spectra

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The de Broglie Wavelength

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The Uncertainty Principle

Werner Heisenberg considered the limits of how accurately one can measure properties of an electron or other microscopic particles. He determined that ...

The Quantum-Mechanical Model of an Atom

Shortly after de Broglie published his ideas that the electron in a hydrogen atom could be better thought of as being a circular standing wave instead of ...

Explore the scientific theory of atoms (also known as atomic theory) by describing changes in the atomic model over time and why those changes were necessitated by experimental evidence.

SC.912.P.8.3

Elements: Chemical Symbols and Isotopes

A chemical symbol is an abbreviation used to indicate an element or an atom of an element. For example, the symbol for mercury is Hg. The same symbol is ...

Ions and Ionic Charges

In ordinary chemical reactions, the nucleus &mdash; which contains the protons and neutrons of each atom and thus identifies the element &mdash; remains ...

The Periodic Table

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Atomic Mass

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Atomic Number and Mass Number

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Explore the scientific theory of atoms (also known as atomic theory) by describing the structure of atoms in terms of protons, neutrons and electrons, and differentiate among these particles in terms of their mass, electrical charges and locations within the atom.

SC.912.P.8.4

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 ...

Electron Configurations

Electron configurations and orbital diagrams can be determined by applying the Aufbau principle (each added electron occupies the subshell of lowest ...

Electronic Structure of Atoms


An atom comprises protons and neutrons, which are contained inside the dense, central&#160;core called the nucleus, with electrons present around the ...

Electron Behavior

Electrons are negatively charged subatomic particles that are attracted to an orbit around the positively-charged nucleus of an atom. They reside in ...

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 ...

Atomic Orbitals

An atomic orbital represents the three-dimensional regions in an atom where an electron has the highest probability to reside. The radial distribution ...

The Pauli Exclusion Principle

The arrangement of electrons in the orbitals of an atom is called its electron configuration. We describe an electron configuration with a symbol that ...

The Energies of Atomic Orbitals

In an atom, the negatively charged electrons are attracted to the positively charged nucleus. In a multielectron atom, electron-electron repulsions are ...

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 ...

electron-configuration-of-multielectron-atoms

Electron Configuration of Multielectron Atoms

The alkali metal sodium (atomic number 11) has one more electron than the neon atom. This electron must go into the lowest-energy subshell available, the ...

Relate properties of atoms and their position in the periodic table to the arrangement of their electrons.

SC.912.P.8.5

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 ...

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 ...

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 ...

Bonding in Metals

Metallic bonds are formed between two metal atoms. A simplified model to describe metallic bonding has been developed by Paul Dr&#xFC;de called the ...

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 ...

Distinguish between bonding forces holding compounds together and other attractive forces, including hydrogen bonding and van der Waals forces.

A. A working definition of matter is that it takes up space, has mass, and has measurable properties. Matter is comprised of atomic, subatomic, and elementary particles.

B. Electrons are key to defining chemical and some physical properties, reactivity, and molecular structures. Repeating (periodic) patterns of physical and chemical properties occur among elements that define groups of elements with similar properties. The periodic table displays the repeating patterns, which are related to the atom's outermost electrons. Atoms bond with each other to form compounds.

C. In a chemical reaction, one or more reactants are transformed into one or more new products. Many factors shape the nature of products and the rates of reaction. 

D. Carbon-based compounds are building-blocks of known life forms on earth and numerous useful natural and synthetic products.

Hydrogen Bonding and DNA Stability

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