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This illustration shows two sister chromatids. Each has a kinetochore at the centromere, and mitotic spindle microtubules radiate from the kinetochore.
During prometaphase, mitotic spindle microtubules from opposite poles attach to each sister chromatid at the kinetochore. In anaphase, the connection between the sister chromatids breaks down, and the microtubules pull the chromosomes toward opposite poles.

During metaphase    , the “change phase,” all the chromosomes are aligned in a plane called the metaphase plate    , or the equatorial plane, midway between the two poles of the cell. The sister chromatids are still tightly attached to each other by cohesin proteins. At this time, the chromosomes are maximally condensed.

During anaphase    , the “upward phase,” the cohesin proteins degrade, and the sister chromatids separate at the centromere. Each chromatid, now called a chromosome, is pulled rapidly toward the centrosome to which its microtubule is attached. The cell becomes visibly elongated (oval shaped) as the polar microtubules slide against each other at the metaphase plate where they overlap.

During telophase    , the “distance phase,” the chromosomes reach the opposite poles and begin to decondense (unravel), relaxing into a chromatin configuration. The mitotic spindles are depolymerized into tubulin monomers that will be used to assemble cytoskeletal components for each daughter cell. Nuclear envelopes form around the chromosomes, and nucleosomes appear within the nuclear area.

Cytokinesis

Cytokinesis , or “cell motion,” is the second main stage of the mitotic phase during which cell division is completed via the physical separation of the cytoplasmic components into two daughter cells. Division is not complete until the cell components have been apportioned and completely separated into the two daughter cells. Although the stages of mitosis are similar for most eukaryotes, the process of cytokinesis is quite different for eukaryotes that have cell walls, such as plant cells.

In cells such as animal cells that lack cell walls, cytokinesis follows the onset of anaphase. A contractile ring composed of actin filaments forms just inside the plasma membrane at the former metaphase plate. The actin filaments pull the equator of the cell inward, forming a fissure. This fissure, or “crack,” is called the cleavage furrow    . The furrow deepens as the actin ring contracts, and eventually the membrane is cleaved in two ( [link] ).

In plant cells, a new cell wall must form between the daughter cells. During interphase, the Golgi apparatus accumulates enzymes, structural proteins, and glucose molecules prior to breaking into vesicles and dispersing throughout the dividing cell. During telophase, these Golgi vesicles are transported on microtubules to form a phragmoplast (a vesicular structure) at the metaphase plate. There, the vesicles fuse and coalesce from the center toward the cell walls; this structure is called a cell plate    . As more vesicles fuse, the cell plate enlarges until it merges with the cell walls at the periphery of the cell. Enzymes use the glucose that has accumulated between the membrane layers to build a new cell wall. The Golgi membranes become parts of the plasma membrane on either side of the new cell wall ( [link] ).

Questions & Answers

What are other types of cell
ATAMA Reply
plant and animal cell
Jessy
prokaryotic and eukaryotic cell
Joneth
meaning inside and outside cells
Joneth
external feature of earthworm
Ajas Reply
what is the reason behind that before F2 generation is no segregation?
asmamaw Reply
what is mitosis and meiosis
Rabiu Reply
hypothesis theory law
Tamba Reply
what is hypothesis theory law
Tamba
Briefly describe the process of mitosis and meiosis.
Lilian Reply
what is chromosome
Deborah Reply
Chromosome is the thread-like structure containing DNA and found in the nucleus of a cell. DNA contains gene which has genetic information.
Lilian
if a cell is killed by strain why then is it use
uchenna Reply
what is an atom
Finda Reply
an atom is the must smallest element in the world.
Young
please help me friends. I wont a good example of lab report based on carbohydrate,lipid,reducing and non reducing sugar.
Ng
that can't be split by any chemical means
uchenna
No an atom is the smallest particles of an element which can take part in a chemical reaction
Solayemi
An atom is the smallest indivisible particle of an element which can take part in a chemical reaction.
Samuel
sure atoms can't be splited
Solayemi
atom can't be split
john
what is molecule
john
Molecules consists of one or more tiny particles called atom
Rofiah
atoms joined together by covalent bonds
Bad
an atom is a particle that cannot be divided further by a chemical reaction
Bad
how do earthworms excrete
Ndlovu
what is genotype
Precious Reply
What is the difference between longitudinal section and vertical section
dela Reply
what is a cell
Young Reply
A cell is the basic unit of Life
Sondja
And what is life...?
ShAmy
it's being.
ernest
how many layers does the eye have
Gift
Three
Winifred
Cell is the basic unit of life
dela
what is virus
Khalid
building block of life
Stanisla
what is diffusion
Precious
excretory system of earthworm
Okotiti Reply
what is flaccidity
Joshua Reply
a condition of composure in respective to the object
Gula
variety of organisms
Abdulkudusi Reply

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Source:  OpenStax, Biology. OpenStax CNX. Feb 29, 2016 Download for free at http://cnx.org/content/col11448/1.10
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