Name: cell ph and organelle balance
Uploaded: 2023-04-30T11:41:42.000Z
Duration: 1 min 28 s
Channel: JoVE

K12 Standards

north-carolina-k-12-science-standard-course-of-study

NC K-12 Science Standard Course of Study

9-12

Biology

from-molecules-to-organisms-structures-and-processes

From Molecules to Organisms- Structures and Processes

LS.Bio.1.1

pH Regulation in Cells

Le pH est une mesure de la concentration en H+ dans une solution et indique son niveau d’acidité ou d’alcalinité.
L’échelle de pH varie de 0 à 14, où sept est considéré comme neutre, une valeur inférieure à sept est acide et une valeur supérieure à sept est basique.
Le pH cytoplasmique typique se situe dans une plage légèrement alcaline de 7,0 à 7,4. De grandes variations de ce pH intracellulaire peuvent affecter des processus cellulaires critiques, tels que le métabolisme, le potentiel membranaire et les voies de signalisation.
Par exemple, le CO2 – le produit final de la respiration cellulaire – se combine avec H2O pour former H2CO3 .
H2CO3 est un acide faible qui se dissocie facilement, acidifiant lentement le cytoplasme et entraînant un stress cellulaire.
Par conséquent, les cellules régulent leur pH interne à l’aide d’échangeurs d’ions pour modifier la concentration en ions hydrogène.
L’échangeur Na+/H+ permet d’équilibrer le pH intracellulaire en couplant l’efflux de H+ avec l’afflux de Na+.
De même, les échangeurs Cl−-HCO3− jouent un rôle important dans le maintien du pH intracellulaire en émettant des ions HCO3− en échange d’ions Cl−.

régulation du ph dans les cellules

Le pH joue un rôle essentiel dans le maintien des activités cellulaires normales. Il aide à maintenir la structure et la fonction de diverses protéines, dicte la charge sur les membranes cellulaires et est crucial pour les réactions métaboliques à l'intérieur de la cellule. De plus, les cellules utilisent l’énergie de la force motrice des protons pour générer de l’ATP.

pH Cytosolique

Dans des conditions physiologiques, le pH cytosolique est légèrement plus acide que le pH extracellulaire. Cependant, les cellules doivent empêcher une acidification supplémentaire de leur cytosol pour maintenir leur potentiel membranaire et fonctionner normalement. Par conséquent, ils utilisent plusieurs machines spécialisées de translocation de protons – antiporteurs, symporteurs et ATPases pompant les protons – pour réguler étroitement le pH à l’état d’équilibre.

Organites Cellulaires et Homéostasie du pH

La compartimentation à l'intérieur des cellules eucaryotes contribue à fournir des conditions environnementales distinctes pour remplir des fonctions spécifiques au sein de différents organites membranaires. Le pH interne de ces différents compartiments est très variable, mais il constitue un déterminant important de leur fonctionnement efficace.

Par exemple, les cytochromes situés sur la membrane mitochondriale interne effluent les protons en utilisant l'énergie du flux d'électrons. Cela aide à établir un gradient de protons à travers la membrane mitochondriale qui est utilisé pour générer de l’énergie chimique sous forme d’ATP. De même, les lysosomes maintiennent un pH acide interne en pompant les protons du cytosol en utilisant l'énergie de l'hydrolyse de l'ATP. Ceci est essentiel au fonctionnement des enzymes lysosomales.

Cependant, certains organites, notamment le noyau, le réticulum endoplasmique et les peroxysomes, doivent maintenir leur pH interne en équilibre avec le cytoplasme. Par conséquent, ils manquent de systèmes intrinsèques de régulation du pH et sont très perméables aux protons.

Dysrégulation du pH Intracellulaire

Certaines conditions métaboliques ou génétiques peuvent perturber le pH à l'état d'équilibre du cytoplasme ou des organites à l'intérieur de la cellule et conduire à des maladies. Par exemple, des mutations chez les porteurs de chlorure, tels que CLCN6 et CLCN7, présents sur les endosomes et les lysosomes tardifs, ont été associées à l'ostéoporose et à la maladie de surcharge lysosomale. De même, les mutations du canal CLCN5 entravent l’acidification luminale et la production d’endosomes précoces dans les cellules épithéliales rénales et peuvent éventuellement conduire à une insuffisance rénale.

Régulation du pH dans les Cellules

Le pH joue un rôle essentiel dans le maintien d’activités cellulaires normales. Il aide à maintenir la structure et la fonction de diverses protéines, dicte la charge ...

Education

Enseignement

JoVE Core

Cell Biology

Biologie cellulaire

Unit 1

Unité 1

Biochemistry of the Cell

Biochimie de la cellule

KEY TERMS AND CONCEPTS

TERMES ET CONCEPTS CLÉS

cell ph and organelle balance

Cell pH and organelle balance are essential for normal cell function. pH affects protein shape and activity, the charge on cell membranes, and many metabolic reactions inside the cell. Cells also use the proton motive force, which is the energy stored in a proton gradient, to make ATP, the cell’s main energy molecule.

The cytosol, or fluid inside the cell, is usually slightly more acidic than the fluid outside the cell. Even so, cells must stop the cytosol from becoming too acidic. They use proton-translocating machinery, including antiporters, symporters, and proton-pumping ATPases, to keep steady-state pH under control and preserve membrane potential.

Eukaryotic cells also separate functions into membrane-bound organelles with different internal pH levels. This compartmentalization creates the conditions needed for each organelle to work properly. In mitochondria, cytochromes on the inner membrane move protons using energy from electron flow. This builds the proton gradient that helps produce ATP. Lysosomes keep an acidic interior by pumping protons from the cytosol with energy from ATP hydrolysis, which is needed for lysosomal enzymes to function.

Some organelles need their internal pH to stay close to the cytoplasm. These include the nucleus, endoplasmic reticulum, and peroxisomes. They do not have their own pH-control systems and are highly permeable to protons, so their pH stays in equilibrium with the cytosol.

Problems with intracellular pH can cause disease. Changes in metabolism or gene function can disturb the steady-state pH of the cytoplasm or organelles. Mutations in chloride carriers such as CLCN6 and CLCN7, which are found on late endosomes and lysosomes, have been linked to osteoporosis and lysosomal storage disease. Mutations in the CLCN5 channel can block luminal acidification and early endosome formation in renal epithelial cells, and this can eventually lead to kidney failure.

Cell pH and Organelle Balance

the periodic table and organismal elements

the-periodic-table-and-organismal-elements

Elements in the Human Body and Periodic Table

Elements are the smallest units of matter that cannot be broken down further by chemical processes. Scientists know 118 elements, but not all of them occur naturally. Only a small number are essential for life, and living matter depends mostly on carbon, nitrogen, hydrogen, and oxygen. The periodic table organizes elements by their physical and chemical properties. Each square shows the element name, chemical symbol, atomic number, and atomic weight. The atomic number is the number of protons...

functional groups

Functional Groups in Organic Molecules

Functional groups are the part of an organic molecule that gives it specific chemical behavior. They help explain why compounds with similar carbon skeletons can react in different ways. In organic chemistry, these groups are often used to classify compounds. A functional group can change the properties of a molecule and affect how it behaves in a reaction. Knowing functional groups helps students recognize patterns in organic compounds. It also makes it easier to compare molecules that share...

types of chemical bonds

Chemical Bonds and How Atoms Join

Chemical bonds hold atoms together and help explain how different substances form. In chemistry, the main bond types are ionic bonds, covalent bonds, and metallic bonds. Ionic bonds form when electrons move from one atom to another. Covalent bonds form when atoms share electrons. Metallic bonds occur in metals, where electrons are held in a shared arrangement that gives metals their characteristic behavior. Understanding these bond types helps students compare how atoms connect in different...

noncovalent attractions in biomolecules

Biomolecule Interactions Without Covalent Bonds

Biomolecules often stay together through noncovalent attractions instead of covalent bonds. These weaker interactions help molecules recognize each other and form structures needed for life. The main noncovalent attractions are hydrogen bonds, electrostatic interactions, van der Waals forces, and hydrophobic interactions. Each one works in a different way, but all of them can influence how biomolecules fold, bind, and behave in cells. Hydrogen bonds form when a hydrogen atom is attracted to...

polymers

Polymer Chains and Their Properties

Polymers are large molecules made from repeating units called monomers. These long chains can form many common materials. Their structure helps explain why different polymers can behave in different ways. Polymers can be built in more than one way. Some form by addition polymerization, where monomers join together directly. Others form by condensation polymerization, which releases a small molecule as the chain grows. The type of polymer affects its properties and uses. Some polymers are...

what are lipids?

Lipids in Cells: Membranes, Energy, and Signals

Lipids are important cell molecules that act as membrane parts, energy stores, and signaling molecules. They are a diverse group of hydrocarbons, which are compounds made of carbon and hydrogen atoms. The carbon-carbon and carbon-hydrogen bonds are nonpolar, so lipids have an overall nonpolar character. Lipids are also hydrophobic, or “water-hating.” They do not form hydrogen bonds with water, so they are nearly insoluble in water. They are, however, soluble in organic solvents such as...

structure of lipids

How Lipid Molecules Are Built

Lipid molecules are built from hydrocarbon chains and a few key structural parts. Their shape helps explain why they behave differently from many other biological molecules. In high school biology, this structure is often linked to how lipids store energy and help form cell membranes. Some lipids are made from fatty acids joined to other small molecules. Triglycerides contain glycerol and three fatty acids, while phospholipids contain glycerol, two fatty acids, and a phosphate group. These...

chemistry of carbohydrates

Carbohydrate Structure and Bonding

Carbohydrates are built from sugar units and the bonds that link them. Their chemistry explains how simple sugars join to form larger molecules. It also helps show why carbohydrates have different structures and functions. The video focuses on the main sugar types found in carbohydrates. These include monosaccharides, disaccharides, and polysaccharides. Monosaccharides are single sugar units. Disaccharides contain two sugar units, while polysaccharides are long chains of many sugar units. The...

nucleic acids

DNA and RNA in Cells

DNA and RNA are nucleic acids that help store and use genetic information in cells. They are key molecules in biology and are often studied together because they work as a pair in living systems. Nucleic acids are built from repeating units called nucleotides. Each nucleotide has a sugar, a phosphate group, and a nitrogenous base. The order of these bases carries the genetic code. There are two main nucleic acids: DNA, or deoxyribonucleic acid, and RNA, or ribonucleic acid. DNA usually stores...

protein and protein structures

How Protein Shape Determines Function

Proteins are essential molecules in living things, and their shape affects how they work. Protein structure is described at several levels, including primary, secondary, tertiary, and quaternary structure. These levels help explain how a protein is built and how its final form supports its job. Primary structure is the sequence of amino acids in a protein. Secondary structure forms when parts of the chain fold into regular patterns. Tertiary structure is the overall three-dimensional shape of...

ph regulation in cells

Cell pH and organelle balance are essential for normal cell function. pH affects protein shape and activity, the charge on cell membranes, and many metabolic reactions inside the cell. Cells also use the proton motive force, which is the energy stored in a proton gradient, to make ATP, the cell’s main energy molecule. The cytosol, or fluid inside the cell, is usually slightly more acidic than the fluid outside the cell. Even so, cells must stop the cytosol from becoming too acidic. They use...

chemistry of the cell

Cell Chemistry: Water, Ions, and Molecules

Cell chemistry explains the substances that make cells work. Water is the main component of cells, and it supports the chemical reactions that keep life going. Cells also contain organic molecules, which are carbon-based compounds, and inorganic ions, which are charged particles needed for cell function. Organic molecules in cells include carbohydrates, lipids, proteins, and nucleic acids. These molecules have different roles, but together they build cell structures, store energy, and carry...

key terms and concepts

Learn how cells control cytosolic pH and organelle acidity using proton pumps, gradients, and transporters, and why pH problems can cause disease.

Cell pH and Organelle Balance | JoVE K12

cell biology

JoVE Core Biologie cellulaire illustre les processus cellulaires complexes dans des leçons vidéos complètes mais faciles à comprendre. Cette collection se concentre sur les composants et fonctions essentiels de la cellule ; cela inclut les organelles et les membranes ainsi que le transport et le métabolisme énergétique cellulaire. Elle est complétée par nos vidéos de scientifiques à l'action qui démontrent l'application de la biologie cellulaire dans des expériences concrètes.

Virginia  Standards of Learning

HIgh School

BIO.2

BIO.2.b

BIO.6

BIO.6.a

Alabama Course of Study Science

From Molecules to Organisms: Structures and Processes

9-12.B.1.1

Compounds Essential to Human Function

The human body is composed of cells that are fundamentally made up of several different molecules. These molecules are essential to carry out all ...

Macromolecules

Biomolecules
Organisms contain a wide variety of organic molecules with numerous functions which depend on the chemical structures and properties of these ...

Solution Preparation
ExpandCAUTION: It is important to always use care when handling reagents. For example, iodine will stain clothes and skin so wear ...

Identifying Macromolecules with Indicator Solutions
ExpandHYPOTHESES: In this activity, the experimental hypothesis might be that the addition of an ...

pH plays a critical role in maintaining normal cellular activities. It helps maintain the structure and function of various proteins, dictates the charge ...

Chemistry of the Cell

Overview of Functional Groups

Functional groups are a group of atoms with characteristic properties, which when linked to the carbon skeleton of a molecule, alter the properties of ...

Introduction to Carbohydrates

Carbohydrates, proteins, and fats are the primary macronutrients in the human diet. However, carbohydrates are the most favored source of energy in the ...

Carbohydrate Metabolism

Sugars as Energy Storage Molecules

What are Lipids?

lipid-derived-compounds-in-the-human-body

Lipid-derived Compounds in the Human Body

Fats and lipids are crucial components in the human body. Some lipid-derived compounds, such as fat-soluble vitamins, eicosanoids, lipoproteins, and ...

Fats as Energy Storage Molecules

What are Proteins?

Protein Organization

Globular Proteins

In organisms, proteins are the most abundant macromolecules. They act as the building blocks of life and play various crucial roles in the body. Proteins ...

Fibrous Proteins

Fibrous proteins are either long and narrow proteins or assemble to form long and thin structures. They contain repetitive units and usually consist of ...

Protein Denaturation

The function of proteins depends on their native three-dimensional structure, which is dictated by the amino acid sequence of the specific protein. ...

Role of Proteins in the Human Body

Proteins are the building block of life. They are also&#160; the most abundant macromolecules with as many diverse roles in the body. They are part of ...

Nucleic Acids and Nucleotides

Nucleic acids are the most important macromolecules for the continuity of life. They carry the cell&#39;s genetic blueprint and have instructions for its ...

Nucleic Acid Structure

The pentose sugar in DNA is deoxyribose, while in RNA the pentose sugar is ribose. The difference between the sugars is the presence of the hydroxyl group ...

ATP Energy Storage and Release

ATP and Macromolecule Synthesis

Biological macromolecules are organic compounds, predominantly composed of carbon atoms. The carbon atoms are covalently bonded with hydrogen, oxygen, ...

Construct an explanation to illustrate relationships between structure and function of major macromolecules essential for life.

Introduction to Enzymes

The use of enzymes by humans dates to 7000 BCE. Humans first used enzymes to ferment sugars and produce alcohol without knowing that this was an ...

Enzymes and Activation Energy

The activation energy (or free energy of activation), abbreviated as Ea, is the small amount of energy input necessary for all chemical reactions to ...

Introduction to Enzyme Kinetics

Enzyme kinetics studies the rates of biochemical reactions. Scientists monitor the reaction rates for a particular enzymatic reaction at various substrate ...

Turnover Number and Catalytic Efficiency

The turnover number of an enzyme is the maximum number of substrate molecules it can transform per unit time. Turnover numbers for most enzymes range from ...

Catalytically Perfect Enzymes

The theory of catalytically perfect enzymes was first proposed by W.J. Albery and J. R. Knowles in 1976. These enzymes catalyze biochemical reactions at ...

introduction-to-mechanisms-of-enzyme-catalysis

Introduction to Mechanisms of Enzyme Catalysis

For many years, scientists thought that enzyme-substrate binding took place in a simple &#34;lock-and-key&#34; fashion. This model stated that the enzyme ...

Ligand Binding and Linkage

Cooperative Allosteric Transitions

Ribozymes

Carry out investigations to illustrate how enzymes act as catalysts for biochemical reactions and how environmental factors affect enzyme activity.

LS.Bio.1.2

What are Cells?

Cells are the smallest and basic units of life, whether it is a single cell that forms the entire organism, e.g., in a bacterium or trillions of them, ...

Cell Size

Cell sizes vary widely among and within organisms. Bacterial cells range between 1-10 micrometers (&#x3BC;m)and are considerably smaller than most ...

Eukaryotic Compartmentalization

One of the distinguishing features of eukaryotic cells is that they contain membrane-bound organelles, such as the nucleus and mitochondria, that carry ...

Prokaryotic Cells

Prokaryotes are small unicellular organisms that include the domains&#x2014;Archaea and Bacteria. Bacteria include many common organisms, such as ...

Cytoplasm

The cytoplasm consists of organelles and a framework of protein scaffolds called the cytoskeleton suspended in an aqueous solution, the cytosol. The ...

The Nucleus

The nucleus is a membrane-bound organelle that acts as a control center in a eukaryotic cell. It contains chromosomal DNA, which controls gene expression ...

Endoplasmic Reticulum

Endoplasmic ReticulumThe endoplasmic reticulum (ER) is an extensive network of membranous sacs and tubules in eukaryotic cells, continuous with the outer ...

Ribosomes

Ribosomes translate genetic information encoded by messenger RNA (mRNA) into proteins. Both prokaryotic and eukaryotic cells have ribosomes. Cells that ...

Golgi Apparatus

As they leave the Endoplasmic Reticulum (ER), properly folded and assembled proteins are selectively packaged into vesicles. These vesicles are ...

Lysosomes

Lysosomes are membrane-enclosed spherical sacs derived from the Golgi apparatus. The most important function of the lysosome is degrading macromolecules ...

Peroxisomes

Peroxisomes and mitochondria are two important oxygen-utilizing organelles in eukaryotic cells. Mitochondria carry out cellular respiration&#x2014;the ...

Introduction to the Cytoskeleton

Overview of the Cytoskeleton
The cytoskeleton is a network of protein filaments present within the cell, having three distinct filaments ...

Introduction to Actin

Actin is a highly conserved cytoskeletal protein found abundantly in eukaryotic cells. It constitutes 10% weight of the total cellular protein in muscle ...

Cell Structure

Background
Cells represent the most basic biological units of all organisms, whether it be simple, single-celled organisms like bacteria, or large, ...

overview-of-myosin-structure-and-function

Overview of Myosin Structure and Function

Myosins are a family of molecular motor proteins, first identified in the skeletal muscles, where they are responsible for muscle contraction. Along with ...

Visualizing Onion and Cheek Cells
ExpandImmediately before the experiment, wash and peel onion bulbs for the class.
Remove the entire brown outer skin and ...

Microtubules

Microtubules are the thickest cytoskeletal filaments with a diameter of 25 nm. In prokaryotic organisms, microtubules are commonly found in locomotory ...

The Structure of Intermediate Filaments

The intermediate filaments are one of three widely studied cytoskeletal filaments. They are so named as their diameter (10 nm) is in between that of ...

Types of Intermediate Filaments

The intermediate filaments are an essential component of the cytoskeleton. Presently six types of intermediate filament have been identified. Type I and ...

Gap Junctions

Multicellular organisms employ a variety of ways for cells to communicate with each other. Gap junctions are specialized proteins that form pores between ...

The Extracellular Matrix

In order to maintain tissue organization, many animal cells are surrounded by structural molecules that make up the extracellular matrix (ECM). Together, ...

Tissues

Cells with similar structure and function are grouped into tissues. A group of tissues with a specialized function is called an organ. There are four main ...

Plant Cell Wall

The plant cell wall gives plant cells shape, support, and protection. As a cell matures, its cell wall specializes according to the cell type. For ...

Plasmodesmata

The organs in a multicellular organism&#x2019;s body are made up of tissues formed by cells. To work together cohesively, cells must communicate. One way ...

Use models to explain how the structure of organelles determines its function and supports overall cell processes.

LS.Bio.1.3

Cells are the smallest and basic units of life, whether it is a single cell that forms the entire organism, e.g., in a bacterium, or trillions of them, ...

the-tree-of-life-bacteria-archaea-and-eukaryotes

The Tree of Life - Bacteria, Archaea, and Eukaryotes

Prokaryotes are small unicellular organisms that include the domains &#8212; Archaea and Bacteria. Bacteria include many common microorganisms, such as ...

Prokaryotic vs. Eukaryotic Cells

Prokaryotic and eukaryotic cells represent two fundamental types of cellular organization, differing significantly in structure, complexity, and function. ...

Construct explanations to compare prokaryotic and eukaryotic cells in terms of structures and degree of complexity.

LS.Bio.1.4

The DNA Helix

Deoxyribonucleic acid, or DNA, is the genetic material responsible for passing traits from generation to generation in all organisms and most viruses. DNA ...

The Central Dogma

The central dogma explains the flow of genetic information from DNA nucleotides to the amino acid sequence of proteins.
RNA is the Missing Link Between ...

What is Gene Expression?

A gene is a stretch of DNA that serves as the blueprint for functional RNAs and proteins. Since DNA is comprised&#160; of nucleotides and proteins are ...

RNA Structure

The basic structure of RNA consists of a string of ribonucleotides attached by phosphodiester bonds. Although most RNA is single-stranded, it can form ...

Types of RNA

Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse ...

Construct an explanation to summarize how DNA and RNA direct the synthesis of proteins.

LS.Bio.1.5

Analyze how the relationship between structure and function supports life processes within organisms.

Cell pH and Organelle Balance

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