2. Cell follows definite stages of
growth, duplication and division
known as the CELL CYCLE.
This cycle involves distinct and
regular phases of growth and repair
If this cellular cycle goes out of
control, abnormal cell growth can
occur and it can be manifest in the
body of the organism
5. Gap 1(G1)
The cell carries out its normal
metabolic functions
Cells also increase their size as
their organelles increase in
number.
Cells spend most of their lives in
this phase, though the length
differ among cell types
Cells have a size limit.
6. Synthesis (S)
The time that the cell makes a copy of the genetic
material in the form of nuclear DNA
The cell spends considerable amount of time and
energy to make copy of its chromosomes
DNA replication- ensures that the daughter cell
receives exact copies of the parents genetic
material during cell division
It also produce a copy of protein complex that will
later help the cell organize its content.
After completion, the cell continues to grow then
prepares for cell division.
7. Gap 2(G2)
Cell continues to carry out their
normal functions and also
undergo further growth
The cell make sure that
everything is in order(size and
DNA without damage)
8. Mitosis (M)
Division of the nucleus and the genetic
material
Prophase, Metaphase, Anaphase,
Telophase
The hereditary material of the parent cell is
given to the daughter cell, that leads to the
formation of two daughter cells
The cell nuclear membrane disintegrates,
while DNA condense forming two nuclei
9. Cytokinesis
Divides the cytoplasm of the
cell
Begins early during telophase
and continues after the nuclei
have formed in the daughter cell
11. Prokaryotic cells have similar structures with
eukaryotic cells but not identical.
Prokaryotic cells lack membrane bound organelles
and cytoskeleton that make them divide more
rapidly.
Cell division is faster during embryonic age and
childhood.
Cell replacement is higher in areas subjected to lot
of wear and tear (skin and intestinal layer)
Intestinal cells(every few days)
Intestinal lining, lung, heart, kidney (occasionally.
Injury or cell death)
Skin cells(after a few weeks)
Liver cells(when repaiir is needed)
12. Gap 0 (G0)
Cells are unlikely to divide but still
continue to perform normal function
Neuron cells and heart muscle cells that
are highly differentiated or specialized that
the body cannot easily replace
Neuron(lymphocytes)- remain in the body
until the body recognize an invader
14. Mitosis
Division of nucleus into genetically
identical nuclei containing the same full
set of DNA
Prepares the cell for the cytokiniesis
15. Prophase: start of Mitosis
1. Chromatin condenses into tightly coiled
chromosomes, that consists of two identical
sister chromatid
The chromosomes are packaged into neat
bundles for an easy movement when the
division starts
2. the nuclear envelopes breakdown
The nucleolus also disappears.
