Mitosis is the phase of the cell cycle where the nucleus of a cell is divided into two nuclei with an equal amount of genetic material in both the daughter nuclei. every detail is available @biOlOgy BINGE-insight learning

1. MITOSIS
THE EQUATIONAL DIVISION
VIDEO LESSON available @biOlOgy BINGE-insight learning (youtube channel)

2. What is mitosis?
 Mitosis is the phase of the cell cycle where the
nucleus of a cell is divided into two nuclei with
an equal amount of genetic material in both
the daughter nuclei.
 It succeeds the G2 phase and is succeeded
by cytoplasmic division after the separation of
the nucleus.
 Mitosis is essential for the growth of the cells
and the replacement of worn-out cells.

3. Why EQUATIONAL?
 “Mitosis is that step in the cell
cycle where the newly formed DNA
is separated and two new cells are
formed with the same number and
kind of chromosomes as the
parent nucleus.”

4. Before mitosis....what cell
does?
 Before entering mitosis, a cell spends a period of its
growth under interphase. It undergoes the following
phases when in interphase:
1. G1 Phase: This is the period before the synthesis of
DNA.
2. S Phase: This is the phase during which DNA
synthesis takes place.
3. G2 Phase: This is the phase between the end of DNA
synthesis and the beginning of prophase.

6. U need to know.....
A chromosome is a
long DNA molecule with part or all of
the genetic material of an organism.
Most eukaryotic chromosomes
include packaging proteins
called histones which, aided
by chaperone proteins, bind to
and condense the DNA molecule .
Here in this diagram:
(1) Chromatid – one of the two
identical parts of the chromosome
after S phase.
(2) Centromere – the point where
the two chromatids touch.
(3) Short arm
(4) Long arm

8. State of cell before mitosis:
 Let’s start by looking at a cell right before it begins mitosis. This cell is in
interphase (late G2 phase) and has already copied its DNA, so the
chromosomes in the nucleus each consist of two connected copies,
called sister chromatids.
 You can’t see the chromosomes very clearly at this point, because they are
still in their long, stringy, decondensed form.
 This animal cell has also made a copy of its centrosome, an organelle that will
play a key role in orchestrating mitosis, so there are two centrosomes.
 (Plant cells generally don’t have centrosomes with centrioles, but have a
different type of microtubule organizing center that plays a similar role.)

10. Phases of MITOSIS
 Prophase
 Metaphase
 Anaphase
 Telophase

11. Phases of mitosis:

12. PROPHASE
 At the start of prophase there are two identical copies
of each chromosome in the cell due to replication
in interphase.
 These copies are referred to as sister chromatids and
are attached by DNA element called the centromere.
 The main events of prophase are:
 the condensation of chromosomes,
 the movement of the centrosomes,
 the formation of the mitotic spindle, and

14. PROMETAPHASE
 Prometaphase is the phase
of mitosis following prophase and
preceding metaphase,
in eukaryotic somatic cells.
 In prometaphase, the nuclear
membrane breaks apart into numerous
"membrane vesicles", and the

16. METAPHASE
 Metaphase is a stage of mitosis in the eukaryotic cell
cycle in which chromosomes are at their second-most
condensed and coiled stage (they are at their most
condensed in anaphase).
 These chromosomes, carrying genetic information, align in
the equator of the cell before being separated into each of
the two daughter cells.
 In metaphase, the centromeres of the chromosomes
convene themselves on the metaphase plate (or equatorial
plate), an imaginary line that is equidistant from the

18. ANAPHASE
 Anaphase , is the stage of mitosis after the process
of metaphase, when replicated chromosomes are split and
the newly-copied chromosomes (daughter chromatids) are
moved to opposite poles of the cell.
 Chromosomes also reach their overall maximum
condensation in late anaphase, to
help chromosome segregation and the re-formation of the
nucleus.
 While the chromosomes are drawn to each side of the cell,
interpolar microtubules and astral microtubules generate

20. TELOPHASE
 During telophase, the effects
of prophase and prometaphase (the nucleolus and
nuclear membrane disintegrating) are reversed.
As chromosomes reach the cell poles, a nuclear
envelope is re-assembled around each set
of chromatids, the nucleoli reappear, and
chromosomes begin to decondense back into the
expanded chromatin that is present during interphase.
The mitotic spindle is disassembled and remaining
spindle microtubules are depolymerized.
 Cytokinesis typically begins before late telophase and,
when complete, segregates the two
daughter nuclei between a pair of separate daughter
cells.

24. Summarizing it.....