Name: interphase and cell growth
Uploaded: 2025-05-22T09:05:54.000Z
Duration: 56 s
Channel: JoVE

Dans les cellules eucaryotes, la plus grande partie du cycle cellulaire est l’interphase, qui est divisée en trois étapes, G1, S et G2.
 Dans G1, la première phase d’écart, une cellule fille nouvellement générée augmente en taille et se prépare à la duplication de l’ADN dans la phase suivante.
Maintenant, dans S, la phase de synthèse, les cellules dupliquent leur ADN nucléaire, qui reste emballé sous forme de chromatine. Les cellules dupliquent également les centrosomes, la structure organisatrice des microtubules qui forme l’appareil du fuseau mitotique.
Enfin, dans G2, la deuxième phase d’écart, les cellules continuent de croître, multiplient les organites et les protéines nécessaires à la mitose et reconstituent leurs réserves d’énergie. La cellule est maintenant prête à entrer dans la première étape de la mitose.

interphase

Interphase

Le cycle cellulaire se déroule sur environ 24 heures (dans une cellule humaine typique) et en deux étapes distinctes : l'interphase, qui comprend trois phases du cycle cellulaire (G1, S et G2), et la mitose (M). Pendant l'interphase, qui représente environ 95 % de la durée du cycle cellulaire eucaryote, les cellules se développent et répliquent leur ADN en préparation pour la mitose.

Phases d'interphase

Après chaque période de mitose et de cytokinèse, les cellules eucaryotes entrent en interphase, au cours de laquelle elles se développent et répliquent leur ADN en préparation pour la division mitotique suivante.

Pendant la phase G1 (espace 1), les cellules se développent continuellement et se préparent à la réplication de l'ADN. Au cours de cette phase, les cellules sont métaboliquement actives et copient les organites essentiels et les molécules biochimiques, telles que les protéines.

Dans la phase S (synthèse) suivante de l'interphase, les cellules dupliquent leur ADN nucléaire, qui reste conditionné dans la chromatine semi-condensée. Au cours de la phase S, les cellules dupliquent également le centrosome, une structure organisatrice de microtubules qui forme l'appareil du fuseau mitotique. Le fuseau mitotique sépare les chromosomes pendant la mitose.

Dans la phase G2 (espace 2), qui suit la synthèse de l'ADN, les cellules continuent de croître et de synthétiser des protéines et des organites pour se préparer à la mitose.

Dans les cellules humaines, la phase G1 dure environ 11 heures, la phase S environ 8 heures et la phase G2 dure environ 4 heures. Pendant G1, les cellules sont diploïdes (2n, une paire de chaque chromosome). Après la réplication en phase S, les cellules augmentent leur teneur en ADN à 4n. Les cellules restent 4n jusqu'à la cytokinèse, moment auquel leur contenu en ADN est réduit à 2n.

Le cycle cellulaire se déroule sur environ 24 heures (dans une cellule humaine typique) et en deux étapes distinctes : l’interphase, qui comprend trois phases de la ...

Education

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JoVE Core

Anatomy and Physiology

Anatomie et physiologie

Unit 1

Unité 1

Essential Cellular Processes

Processus cellulaires essentiels

KEY TERMS AND CONCEPTS

TERMES ET CONCEPTS CLÉS

interphase and cell growth

Interphase is the part of the cell cycle when a cell grows and prepares to divide. It is a major stage of the cell cycle, and it comes before cell division begins.

During interphase, the cell carries out its normal functions. It also copies its DNA so each new cell can receive a full set of genetic material. The cell may also build up the materials it needs for division.

Interphase is not a single step. It includes phases such as G1, S, and G2, which help the cell grow, copy DNA, and get ready for mitosis. These steps keep the cell cycle moving in an orderly way.

Interphase and Cell Growth

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Interphase is the part of the cell cycle when a cell grows and prepares to divide. It is a major stage of the cell cycle, and it comes before cell division begins. During interphase, the cell carries out its normal functions. It also copies its DNA so each new cell can receive a full set of genetic material. The cell may also build up the materials it needs for division. Interphase is not a single step. It includes phases such as G1, S, and G2, which help the cell grow, copy DNA, and get...

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molecular-factors-affecting-cell-division

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key terms and concepts

Learn how interphase supports cell growth, DNA copying, and preparation for mitosis. A clear high school explanation of this key cell cycle stage.

Interphase and Cell Growth | 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.

Interphase and Cell Growth

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