World Library  
Flag as Inappropriate
Email this Article

Interphase

Article Id: WHEBN0000222320
Reproduction Date:

Title: Interphase  
Author: World Heritage Encyclopedia
Language: English
Subject: Cell cycle, Meiosis, Cell nucleus, Chromatin, Cyclin-dependent kinase
Collection: Cell Biology, Mitosis
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Interphase

An illustration of interphase. The chromatin has not yet condensed, and the cell is undergoing its normal functions.
An image of the nucleus of a cell (HT1080) currently in interphase (likely G1). Note: Cytoplasm of this cell or the neighboring cell is not visible (top-left), which is currently in the telophase of mitosis. Image taken using an optical microscope and DAPI staining of DNA.

Interphase is the phase of the cell cycle in which a typical cell spends most of its life.[1] Interphase is the 'daily living' or metabolic phase of the cell, in which the cell obtains nutrients and metabolizes them, grows, reads its DNA, and conducts other "normal" cell functions.[1] The majority of eukaryotic cells spend most of their time in interphase. This phase was formerly called the resting phase. However, interphase does not describe a cell that is merely resting; rather, the cell is actively living, and preparing for later cell division, so the name was changed. A common misconception is that interphase is the first stage of mitosis. However, since mitosis is the division of the nucleus, prophase is actually the first stage.[2]

In interphase, the cell gets itself ready for mitosis or meiosis. Somatic cells, or normal diploid cells of the body, go through mitosis in order to reproduce themselves through cell division, whereas diploid germ cells (i.e., primary spermatocytes and primary oocytes) go through meiosis in order to create haploid gametes (i.e., sperm and ova) for the purpose of sexual reproduction. Chromosomes are copied.

Contents

  • Stages of interphase 1
  • Interphase within sequences of cellular processes 2
    • Interphase and the cell cycle 2.1
    • Interphase and other cellular processes 2.2
  • References 3

Stages of interphase

There are three stages of interphase, with each phase ending when a cellular checkpoint checks the accuracy of the stage's completion before proceeding to the next. The stages of interphase are:

  • mitochondria and chloroplasts divide. If the cell is not to divide again, it will enter G0.[3]
  • G2 (Gap 2), in which the cell resumes its growth in preparation for division.
  • In addition, some cells that do not divide often or ever, enter a stage called G0 (Gap zero), which is either a stage separate from interphase or an extended G1.

The duration of time spent in interphase and in each stage of interphase is variable and depends on both the type of cell and the species of organism it belongs to. Most cells of adult mammals spend about 20 hours in interphase; this accounts for about 90% of the total time involved in cell division.[4] Interphase includes G1, S, and G2 phases. Mitosis and cytokinesis, however, are separate from interphase.

Interphase within sequences of cellular processes

Interphase and the cell cycle

When G2 is completed, the cell enters a relatively brief period of nuclear and cellular division, composed of mitosis and cytokinesis, respectively. After the successful completion of mitosis and cytokinesis, both resulting daughter cells re-enter G1 of interphase.

In the cell cycle, interphase is preceded by telophase and cytokinesis of the M phase. In alternative fashion, interphase is sometimes interrupted by G0 phase, which, in some circumstances, may then end and be followed by the remaining stages of interphase. After the successful completion of the G2 checkpoint, the final checkpoint in interphase, the cell proceeds to prophase, or in plants to preprophase, which is the first stage of mitosis.

G0 phase is viewed as either an extended G1 phase where the cell is neither dividing nor preparing to divide and or as a distinct quiescent stage which occurs outside of the cell cycle.[5]

Interphase and other cellular processes

In gamete production interphase is succeeded by meiosis. In programmed cell death, interphase is followed or preempted by apoptosis.

References

  1. ^ a b
  2. ^ The Cell Cycle & Mitosis Tutorial The Biology Project – Cell Biology. University of Arizona.
  3. ^ Cummings, M. R. (2014). Human Heredity: Principles and Issues (10th ed., pp. 28-29). Belmont, CA: Brooks/Cole.
  4. ^ Mader, S. S. 2007. Biology 9th Ed. McGraw Hill Higher Education, Boston, MA, USA. ISBN 978-0-07-325839-3
  5. ^ Re: Are the cells in the G0 (g zero) phase of mitosis really suspended? Erin Cram, Grad student, Molecular and Cellular Biology, University of California, Berkeley. 1999. MadScience Network. Question ID 942142089.Cb.
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.