The Cell Cycle

1
The Cell Cycle

• Interphase and Mitosis

2
The Cell Cycle

• Cells must divide to maintain maximum efficiency.
• Mitosis is the process in which somatic (body)
  cells divide to form a new cell.
• Mitosis consists of four phases.
• Interphase is the period in between each mitotic
  cell division.

3
Interphase

• Interphase is made of 3 stages.
• The Gap 1 and 2 or G1 and G2 phase is when cells
  grow and make RNA, proteins, and other
  macromolecules.
• The S or Synthesis phase is when the cell is
  making DNA.

4
DNa Replication

• During the S phase of the cell cycle, DNA
  replicates.
• A short section of the DNA uncoils.
• New nucleotides bond to the open sections of the
  DNA.
• The new and old sections of DNA separate and
  now there are 2 DNA strands.

5

• Replication Animation
• http//www.ncc.gmu.edu/dna/repanim.htm
• http//www.johnkyrk.com/DNAreplication.html
• http//www.lewport.wnyric.org/jwanamaker/animation
  s/DNA20Replication20-20long20.html

6
Interphase

• ATP is synthesized.
• Damaged parts are repaired.
• Wastes are excreted.
• Proteins are made.
• Organelles are formed.
• Chromosomes are copied.
• Specialized tasks are performed .

7
Mitosis

• Mitosis consists of four phases
• Prophase
• Metaphase
• Anaphase
• Telophase

8
Prophase

• Longest phase.
• Chromatin coils.
• Nucleus disappears.
• Centrioles migrate.
• Spindle forms.

9
Metaphase

• Chromatids attach to spindle fibers.
• Chromatids migrate to equator of spindle.

10
Anaphase

• Centromere splits.
• Chromatids are separated.
• Chromatids are now called chromosomes.

11
Telophase

• Cytoplasm divides.
• Nucleus reappears.
• Chromosomes uncoil.

12
Cytokinesis

• In the process called cytokinesis, the cytoplasm
  divides and two identical daughter cells are
  formed.

13
Animation

• http//www.phschool.com/science/biology_place/labb
  ench/lab3/mitfilm.html
• Lab Quiz http//www.phschool.com/science/biology_p
  lace/labbench/lab3/quiz1.html
• http//www.cellsalive.com/mitosis.htm