Lesson 10

Lesson 10
Mitosis
THINK ABOUT IT
What role does cell division play in your life?
Does cell division stop when you are finished growing?
Chromosomes
Genetic information is passed on from one generation to the next by chromosomes.
Every cell must copy its genetic information before cell division begins.
Each daughter cell gets its own copy of that genetic information.
Prokaryote
DNA molecules are found in the cytoplasm.
Eukaryote
Chromosomes are located in the nucleus, and are made up of chromatin
CELL DIVISION
Prokaryote
Cells begin to replicate, or copy, their DNA once they have grown to a certain size.

When DNA replication is complete, the cells divide through a process known as binary fission.
Eukaryote
Cell cycle consists of four phases: G1, S, G2, and M.

Interphase is the time between cell divisions. It consists of the G1, S, and G2 phases.

The M phase is the period of cell division.
P
Q
Interphase
G1 Phase: Increase cell size, make proteins and new organelles

S Phase: New DNA is made and chromosomes are replicated

G2 Phase: Organelles and molecules for cell division are made
Prophase
The first phase of mitosis, the duplicated chromosome condenses and becomes visible.

It is the longest phase of mitosis
Metaphase
The second phase of mitosis, the centromeres of the duplicated chromosomes line up across the center of the cell.
Anaphase
Third phase of mitosis, the centromeres are pulled apart and the chromatids separate to become individual chromosomes.
Telophase
The fourth and final phase of mitosis, the chromosomes spread out into a tangle of chromatin.

The spindle begins to break down.

The nuclear envelope reforms
Cytokinesis
Division of the cytoplasm to form two separate daughter cells
Threadlike structure of DNA and protein that contains genetic information
Humans have 46 chromosomes
1 set of 23 from mom
1 set of 23 from dad
Substance found in eukaryotic chromosomes that consists of DNA tightly coiled around histones
CELL CYCLE: Series of events in which a cell grows, prepares for division and divides to form two daughter cells
A method of asexual reproduction that involves the splitting of a parent cell into two approximately equal parts.
Period of the cell cycle between cell divisions
Mitosis
M Phase: The period of nuclear division

Part of eukaryotic cell division during which the cell nucleus divides

Cytokinesis: Division of the cytoplasm to form two separate daughter cells

Prophase, Metaphase, Anaphase, Telophase
Period of the cell cycle between cell divisions
Region of a chromosome where the two sister chromatids attach
One of two identical "sister" parts of a duplicated chromosome