Download notes from Ch11.1

Ch11.1p265-273
Cell Growth and Reproduction
When do cells divide?
All the time.
Cells multiply to grow bodies larger.
Cell Reproduction19th Century microscopes =
The Role of Chromosomes
understanding of Cells
-The discovery of Chromosomes DNA is always in a cell.
Chromosomes are coiled DNA
-The structure of eukaryotic chromosomes
Chromatine is uncoiled DNA
Uncoiled DNA performs function in cell
The Cell Cycle
The sequence of growth and
division of a cell.
Cells grow and reproduce.
Interphase= cell growth, metabolism,
And DNA replication.
Mitosis= nuclear + cytoplasm division
Interphase- a busy time
Performing the regular functions of the cell
3 parts to interphase
1st= grows + make proteins
2nd= copies chromosomes
3rd= growth, prep for division
The Phases of Mitosis
cell cycle is a continuous process,
4 phases, prophase,
metaphase, anaphase, telophase
Prophase- The first phase of mitosis
DNA coils up to chromosomes
Copies of dna = sister chromatids
Nuclear envelope disappears
Centrioles migrate to opposite ends of cell
ChromotidsLined up between centrioles.
Microtubulals make up the spindle
Metaphase- The 2nd stage of mitosis
Chromosomes become attached to spindle
fibers and line up in middle of cell.
rd
Anaphase- The 3 phase of mitosis
Sister chromatides start to separate moving
toward opposite sides of cell
Telophase- The 4th stage of mitosis
Chromatides reach opposite sides of cell.
Chromatides unwinds to become
chromatine dna again. Nuclear
envelope forms again.
Division of the cytoplasm Plasma
membrane pinches in the middle of
the cell forming two cells from one
= 2 daughter cells
Plants = no pinching in rather formation of
new wall.
Results of mitosis
makes 2 identical cells that perform
identical functions of original cell
Grow until they split again.