1. Cellular Reproduction
Chapter 6: pp

2. Definitions Related to Cell Division
Gene-a segment of DNA that codes for a protein or RNA molecule
Chromatid- one pair of strands of DNA that make up a chromosome
Centromere-

3. Chromosomes-
DNA tightly coiled around proteins
Humans have 46

4. Chromosomes affect Development
Homologous Chromosomes-
Similar in shape size and genetic content
Diploid
2 sets of chromosomes
Haploid
One set of chromosomes
Zygote
Fertilized egg cell, the first cell

5. Chromosomes affect Development
Autosomes
Chromosomes that do not determine sex
Sex Chromosomes
Contain genes that determine male or female
Karyotype
A picture of the chromosomes in a dividing cell that shows the chromosomes arranged by size.

7. The Cell Cycle (Fig 6-6) Interphase: 90% of time First Growth (G1)
In your book
The Cell Cycle (Fig 6-6)
Interphase:
90% of time
First Growth (G1)
Cell grows rapidly
Synthesis Phase (S)
Cell’s DNA copied
Second Growth (G2)
Prepare for Mitosis
                                              

8. Cell Division- 3 types
1. Binary Fission- asexual reproduction that produces identical offspring

9. Cell Division 2. Mitosis – (Fig 6-9) Nucleus of cell divides
In your book
Cells must divide because Surface Area to Volume ratios get too small
Skin Cells

10. Cellular Reproduction
Link!Mitosis
animation

11. Prophase Chromosomes coil up and become visible.
The nuclear envelope dissolves and a spindle forms.

12. Metaphase
Chromosomes move to the middle of the cell and line up along the equator.
Spindle fibers link the chromatids of each chromosome to opposite poles.

13. Anaphase Centromeres divide
Chromatids (now called chromosomes) move toward opposite poles

14. Telophase A nuclear envelope forms around the chromosomes at each pole
Chromosomes uncoil
LAST step in mitosis

15. Cytokinesis (Fig 6-10) Cytoplasm is divided in half.
In your book
Cytokinesis (Fig 6-10)
Cytoplasm is divided in half.
Cell membrane encloses each cell