1. Reproduction Notes

2. I. Asexual Reproduction
Definition – reproduction without sex! A partner is not needed and there is no exchange of DNA.

3. Benefit – fast and easy!
Drawback – no genetic diversity; your offspring are identical to you EVERYTIME!

4. Examples of Asexual Reproduction
Regeneration

5. B. Formation of Spores

6. C. Plant Asexual Reproduction

7. II. Sexual Reproduction
Definition – creating an organism by combining the genetic material of 2 organisms. Fusion of gametes. Gametes are reproductive cells (sperm or egg)

8. Benefits – produces DIVERSITY in a species
Drawback - slow and sometimes difficult

9. Examples of Sexual Reproduction

11. Back To Humans

12. Sperm Cells Formed during a process of cell division called meiosis
Contribute half of father’s DNA (23 chromosomes)
Formed during a process of cell division called meiosis
The combination of genes is different in every single sperm

13. Egg Cells (Ova) Contribute half of mother’s DNA (23 chromosomes)
Also formed during meiosis
Each egg is different!

14. Fertilization fusion of egg and sperm forms a cell called a zygote
(egg) 23 chromosomes
+ (sperm) 23 chromosomes
zygote with 46 chromosomes

15. Identical Twins
One sperm
One egg
Zygote splits in 2
Same DNA

17. Fraternal Twins 2 eggs 2 sperm
Each develops into a baby with a unique set of genes and traits!

19. Formation of the Fetus
The zygote goes through a series of cell divisions called mitosis.
Cells eventually differentiate into different cell types.

20. Gender Father determines baby’s gender Men XY and Women XX
50% chance of either!