Name: cell compartments in eukaryotes
Uploaded: 2020-11-23T11:47:33.000Z
Duration: 1 min 46 s
Channel: JoVE

- [Verteller] Eukaryotische cellen bevatten talrijke interne compartimenten, membraan-gebonden organellen, waardoor zeer specifieke functies kunnen plaatsvinden in micro-omgevingen, beschermd tegen zowel het cytoplasmatische interieur als de extracellulaire omgeving. Bijvoorbeeld, de kern vereist gereguleerde omstandigheden voor een nauwkeurige regeling van de genen in de kern. Daardoor is het omgeven door een dubbele membraan, het kernomhulsel, met poriën om te controleren welke moleculen kunnen in en uittreden, zoals mRNAs.

Bovendien hebben sommige eiwitten een oxidatieve omgeving nodig en moeten ze worden geïsoleerd uit het cytosol, dat reductief is. Hierdoor produceren de ribosomen deze eiwitten binnen het endoplasmatische reticulum, waar ze ook kritische wijzigingen kunnen ondergaan. De daaropvolgende bewegingen vinden zelfs plaats in kleine chemische microkosmossen, vesikels genaamd, terwijl ze op weg zijn naar hun eindbestemming.

Andere organellen, zoals peroxisomen, bieden bescherming tegen hun eigen schadelijke bijproducten, zoals waterstofperoxide, door enzymen die giftige verbindingen omzetten in onschadelijke moleculen, zoals water, op te slaan. Evenzo scheiden lysosomen enzymen, maar om een andere reden, om spijsverteringsreacties te beschermen die een veel lagere pH-waarde vereisen dan waaruit cytoplasma bestaat. Mitochondriën hebben ook zure gedeelten tussen hun twee membranen, die helpen energie te produceren.

In het algemeen ondersteunt eukaryotisch compartimentering handelingen die anders onverenigbaar zouden zijn als ze tegelijkertijd worden uitgevoerd, zonder enige vorm van insluiting.

eukaryotic compartmentalization

Een van de onderscheidende kenmerken van eukaryote cellen is dat ze membraangebonden organellen bevatten, zoals de kern en de mitochondriën, die gespecialiseerde functies uitvoeren. Omdat biologische membranen slechts selectief doorlaatbaar zijn voor opgeloste stoffen, helpen ze bij het creëren van compartimenten met gecontroleerde omstandigheden binnen een organel. Deze micro-omgevingen zijn specifiek afgestemd op de functies van het organel en helpen deze te isoleren van het omringende cytosol.

Lysosomen in dierlijke cellen handhaven bijvoorbeeld een zure omgeving vergeleken met het omringende cytosol. Dit bevordert de activiteit van lysosomale enzymen, die cellulair afval afbreken. Op dezelfde manier speelt pH-regulering in de mitochondriën een cruciale rol bij de synthese van energiemoleculen.

Daarnaast hebben sommige eiwitten een oxidatieve omgeving nodig voor correcte vouwing en verwerking, terwijl het cytosol over het algemeen een reducerend milieu is. Daarom worden deze eiwitten gesynthetiseerd door ribosomen in het endoplasmatisch reticulum (ER), dat de noodzakelijke chemische omgeving in stand houdt. Vervolgens worden de eiwitten via membraangebonden blaasjes naar hun eindbestemming binnen de cel getransporteerd.

Het genetisch materiaal van eukaryote cellen is gecompartimenteerd in de kern, die wordt omgeven door een dubbel membraan, de nucleaire envelop. Kleine poriën in deze envelop reguleren welke moleculen of ionen de kern kunnen binnendringen of verlaten. Zo verlaat messenger-RNA (mRNA) de kern via deze poriën om de genetische instructies, die in het DNA zijn gecodeerd, naar de ribosomen te brengen, waar ze worden vertaald in eiwitten.

Dankzij compartimentering kunnen verschillende functies efficiënter worden uitgevoerd binnen dezelfde cel. Dit gebeurt door de benodigde componenten in een beperkte ruimte te concentreren en ze tegelijkertijd te scheiden van de rest van de cel.

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 ...

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Eukaryotische Compartimentatisatie

cell compartments in eukaryotes

Eukaryotic cells use compartments to organize many different jobs inside one cell. These compartments help separate processes so they can happen in the right place.

The compartment called the cytosol is the fluid part of the cell. It surrounds the other internal structures and helps support many cell processes.

Inside the cell, membrane-bound organelles create distinct microenvironments. A microenvironment is a small internal space with conditions that fit a specific task. This separation lets the cell run different reactions at the same time.

The nucleus is one of the main compartments in eukaryotic cells. It keeps the cell’s genetic material in a protected space and helps separate DNA-related activities from other work in the cytosol.

Compartmentalization is a key feature of eukaryotic cells. It improves organization and helps the cell control where important processes take place.

Cell Compartments in Eukaryotes

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Eukaryotic cells use compartments to organize many different jobs inside one cell. These compartments help separate processes so they can happen in the right place. The compartment called the cytosol is the fluid part of the cell. It surrounds the other internal structures and helps support many cell processes. Inside the cell, membrane-bound organelles create distinct microenvironments. A microenvironment is a small internal space with conditions that fit a specific task. This separation...

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key terms and concepts

Learn how eukaryotic cells use the cytosol, nucleus, and membrane-bound organelles to create microenvironments and organize cell processes.

Cell Compartments in Eukaryotes | JoVE K12

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Cell Compartments in Eukaryotes

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