Chapter 10 Cell Growth and Division

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Transcript Chapter 10 Cell Growth and Division

Section 10-1 & 10-2
Cells divide rather than get larger
because…….
1. Demands on DNA would be too great.
2. Cell would have trouble moving food
and waste across the cell membrane.
Volume increases faster than surface area.
 Each
organism has a specific number of
chromosomes.
 During cell division chromatin condenses into
chromosomes.
 In order for each cell to get the right number
the chromosomes have to double
 Cell
cycle – The series of events that cells
go through as they grow and divide.



G1 – Growth phase #1.
Cells increase in size and
make new proteins and
organelles.
S – Synthesis.
Chromosomes are
replicated.
G2 – Growth Phase #2
Cell division organelles are
produced. Short phase.
Cell division is made up of 2 parts.
1. Mitosis – division of the nucleus.
Divided into 4 phases.
2. Cytokinesis – division of the
cytoplasm.




Chromosomes are visible.
Centrioles separate
Spindle fibers form
Nuclear membrane breaks down.
 Chromosomes
the cell
line up in the middle of
 Chromosomes
are pulled apart/away
from each other.




The opposite of prophase occurs.
Chromosomes disappear back to chromatin
Nuclear membrane reforms
Spindle fibers break apart and disappear
 Cytokinesis
occurs right after Mitosis and
is the division of the cytoplasm.