1. Sexual vs. Asexual Reproduction

2. Extra chromosomes allow all female lizards to reproduce without males  double their chromosomes twice before everything kicks off, creating eight copies of each.  double their chromosomes twice before everything kicks off, creating eight copies of each.

3. 1. Sexual Reproduction  Reproduction - genetic materials from two different sex cells combine, - Sperm & Egg  Fertilization : an egg cell and a sperm cell join together  The new cell is a zygote  Reproduction - genetic materials from two different sex cells combine, - Sperm & Egg  Fertilization : an egg cell and a sperm cell join together  The new cell is a zygote

4. Advantages: Sexual Reproduction 1) Diverse offspring : genetic variation among offspring  Individuals in population have slight differences  Some differences allow for some to resist diseases 1) Diverse offspring : genetic variation among offspring  Individuals in population have slight differences  Some differences allow for some to resist diseases

5. Advantages: Sexual Reproduction 2) Selective Breeding  develop many types of plants and animals that have desirable traits 2) Selective Breeding  develop many types of plants and animals that have desirable traits

6. Disadvantages : Sexual Reproduction 1) Time and Energy  Organisms have to grow and develop until they are old enough to produce sex cells  Search and find a mate  Searching can expose individuals to predators, diseases, or harsh environmental conditions  Fertilization cannot take place during pregnancy, which can last as long as 2 years for some mammals. 1) Time and Energy  Organisms have to grow and develop until they are old enough to produce sex cells  Search and find a mate  Searching can expose individuals to predators, diseases, or harsh environmental conditions  Fertilization cannot take place during pregnancy, which can last as long as 2 years for some mammals.

7. Examples: Sexual Reproduction

8. 2. Asexual Reproduction  One parent: organism produces offspring without fertilization  Uniform offspring: They are genetically identical to each other and to their parent.  One parent: organism produces offspring without fertilization  Uniform offspring: They are genetically identical to each other and to their parent.

9. Examples of Asexual Reproduction 1) Fission : Cell division in prokaryotes that forms two genetically identical cells Ex: bacteria 2) Budding: a new organism grows by mitosis and cell division on the body of its parent. Ex: yeast, hydra, cactus 1) Fission : Cell division in prokaryotes that forms two genetically identical cells Ex: bacteria 2) Budding: a new organism grows by mitosis and cell division on the body of its parent. Ex: yeast, hydra, cactus

10. Examples of Asexual Reproduction 3) Regeneration: occurs when an offspring grows from a piece of its parent. Ex: sea star 4) Vegetative Propagation: uniform offspring grow from a part of a parent plant 3) Regeneration: occurs when an offspring grows from a piece of its parent. Ex: sea star 4) Vegetative Propagation: uniform offspring grow from a part of a parent plant

11. Advantages : Asexual Reproduction 1)Organisms can reproduce without a mate 2) rapidly reproduction 1)Organisms can reproduce without a mate 2) rapidly reproduction

12. Disadvantages : Asexual Reproduction 1) No genetic variation 2)High disease vulnerability 1) No genetic variation 2)High disease vulnerability

13. Examples Examples: Asexual Reproduction

14. Now think of the lizard- exception to the rule  Asexual reproduction yet with genetic variability