Page 16 - Science E-Book Prep.3 2024-2025 1st term_Neat unit 3,4

Science Department
Prep.3

Mitosis (Mitotic) Division:

Before starting division, the cell passes through a
phase is called "Interphase"

During Interphase:
- Some important biological processes occur to
prepare the cell for division.
-The amount of DNA (the genetic material) is
duplicated.

Prophase:

- Chromatin reticulum condenses
then appears in the form of long, thin
and double strings (chromosomes).

- Network of filamentous fibers
called (spindle fibers) are formed
extending between two poles of the cell.

- The nucleolus and nuclear membrane disappear.

- Note:
a. In animal cell spindle fibers formed by centrosome.
b. In plant cell spindle fibers formed by cytoplasm.

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First Term