1. 1
Chromosomes and Mitosis
Chapter 1 Thompson and Thompson

2. 1 Chromosomal Basis of Heredity
• A gene is a unit
of heredity
• Genes are
carried on DNA
• DNA is
contained
within
chromosomes as
chromatin

3. Chromosomes replicate during cell
division

4. The chromosome
complement

5. Chromosome analysis
Cri Du Chat results
from loss of a small
piece of chromosome
5

6. Gene Map

7. Chromosome
pairs

8. Non-identical genes

9. Sex
chromosomes
• These determine the sex of an
individual
– Two X chromosomes make a female
– One X and one Y a male

10. Two types of Cell Division
• Cells divide for two reasons
– To create genetically identical
copies of themselves
• This is
mitosis
– To create gametes that
contain half of the
chromosomes of the original
cell
• This is meiosis
46
46 46
46
23 23 23 23

11. The Cell
Cycle

12. S phase
Replication
Condensation
Schematic

13. DNA replication
Duplex DNA begins Replicating
Replication bubbles merge creating two duplexes

14. Mitosis

15. The stages of Mitosis

16. Prophase Detail

17. Prometaphase

18. Metaphase

19. Anaphase

20. Telophase

21. The sum total of
the process

22. Karyotypes

23. Chromosome
Length

24. Chromosome appearance