1. DNA
Sugar & Phosphate Backbone
Nucleic Acids in Center

5. DNA RNA Replication Ribosome Deletion Insertion New sequence
Mutations
Deletion
Insertion
New sequence
DNA
Replication
RNA
Transcription
Ribosome
Translation
tRNA
Codons

6. Chromosomes

7. Eye Color
Hair type
Blood Type

8. Diploid = Somatic or body cell
Gametes
Haploid
Diploid = Somatic or body cell

9. Keys to Understanding Meiosis
Chromosomes are paired.
Chromosomes carry genes.
The gene forms on a pair of chromosomes may be identical ..
Brown eyes
Tall
Brown eyes
Blue eyes
Tall
Short
or different.

10. One Way Meiosis Makes Lots of Different Sex Cells (Gametes) – Independent Assortment
Independent assortment produces 2n distinct gametes, where n = the number of unique chromosomes.
In humans, n = 23 and 223 ≈ 8,000,0000.
That’s a lot of diversity by this mechanism alone.

11. Another Way Meiosis Makes Lots of Different Sex Cells – Crossing-Over
Crossing-over multiplies the already huge number of different gamete types produced by independent assortment.

12. Between Independent Assortment and Crossing-Over, No Two Gametes Are Identical.

13. Homologous Chromosomes

18. Boy or Girl?
X chromosome
Y chromosome

19. Boy or Girl?

20. Karyotype

23. Nondisjunction- when homologous chromosomes fail to separate
When things go wrong
Nondisjunction- when homologous chromosomes fail to separate

24. Patau Syndrome (Trisomy 13)

25. Trisomy 18 Edwards Syndrom

26. Trisomy 21- down syndrome

28. Monosomy 45, turner syndrome (x)

29. Kleinfelter’s syndrom (xxy)

30. Mitosis / meiosis / problems