2. State Standard 2E. Compare the advantages of sexual reproduction and asexual reproduction in different situations. Meiosis & Sexual Reproduction (10.1)

3.  Human body cells have ____ chromosomes 10.1 Meiosis Sexual Reproduction and Genetics  Each parent contributes ____ chromosomes Chapter 10  ____________ ____________—one of two paired chromosomes, one from each parent Chromosomes & Chromosome Number

4. Chromosomes & Chromosome Number Cont’d 10.1 Meiosis Sexual Reproduction and Genetics  Same __________  Same centromere __________  Carry genes that control the same inherited ________ Chapter 10 Homologous Chromosomes have…

5. These chromosomes have replicated These chromosomes Have not replicated

6. Haploid and Diploid Cells Sexual Reproduction and Genetics  Gametes are __________. The contain half the normal # of chromosomes for the organism. (n) Human gametes = 23 chromosomes  All other body cells (aka somatic cells) are __________. They contain the normal # of chromosomes for the organism. (2n) Human body cells = 46 chromosomes. 10.1 Meiosis  An organism produces __________ to maintain the same number of chromosomes from generation to generation. Chapter 10

7. Meiosis  __________ is a special type of cell division that produces gametes.  Gametes are __________ (n) cells Sexual Reproduction and Genetics 10.1 Meiosis Chapter 10 When 2 gametes combine during fertilization, the __________ (2n) number of chromosomes is restored.

8. Stages of Meiosis  Meiosis __________ the chromosome number (2n) to half (n) through the __________ of homologous chromosomes  Human meiosis reduces the cell from _____ to _____ chromosomes. Sexual Reproduction and Genetics  Involves _____ consecutive cell divisions called Meiosis ___ and Meiosis ___ 10.1 Meiosis Chapter 10

9. Meiosis I - ____________ Sexual Reproduction and Genetics 10.1 Meiosis  Chromosomes replicate.  Chromatin condenses. Chapter 10 Interphase

10. Meiosis I – ____________ Sexual Reproduction and Genetics 10.1 Meiosis  ____________ of homologous chromosomes occurs. (called ____________)  Each chromosome consists of two chromatids.  The nuclear envelope breaks down.  Spindles form. Chapter 10 Prophase I

11. Meiosis I – Prophase I Cont’d Sexual Reproduction and Genetics 10.1 Meiosis  During Prophase I, crossing over creates genetic ____________.  ____________ __________—chromosomal segments are ____________ between a pair of homologous chromosomes. Chapter 10

12. Meiosis I – ____________ Sexual Reproduction and Genetics 10.1 Meiosis  Chromosome centromeres attach to spindle fibers.  Homologous ____________ line up at the equator. Chapter 10 Metaphase I

13. Meiosis I – ____________ Sexual Reproduction and Genetics 10.1 Meiosis Chapter 10 Anaphase I  _________ homologous chromosomes separate and move to opposite poles of the cell.

14. Meiosis I – ____________ Sexual Reproduction and Genetics 10.1 Meiosis  The spindles break down.  Chromosomes uncoil and form two nuclei.  The cell divides.  There is _____ __________ following Meiosis I Chapter 10 Telophase I

15. Meiosis II – __________ Sexual Reproduction and Genetics 10.1 Meiosis Chapter 10  A second set of phases begins as the spindle apparatus forms and the chromosomes condense.  Meiosis II is like ____________. Prophase II

16. Meiosis II – ____________ Sexual Reproduction and Genetics 10.1 Meiosis Chapter 10  A __________ number of chromosomes line up at the equator. Metaphase II

17. Meiosis II – ____________ Sexual Reproduction and Genetics 10.1 Meiosis Chapter 10 Anaphase II  The sister ____________ are pulled apart at the centromere by spindle fibers and move toward the opposite poles of the cell.

18. Sexual Reproduction and Genetics 10.1 Meiosis Meiosis II – ____________ Chapter 10  The chromosomes reach the poles, and the nuclear membrane and nuclei reform. Telophase II

19. Meiosis II - Cytokinesis Sexual Reproduction and Genetics  Cytokinesis results in _____ _________ cells, each with n number of chromosomes.  The 4 daughter cells are ___________ __________. 10.1 Meiosis Chapter 10 Cytokinesis

20. The Importance of Meiosis  Meiosis consists of _____ sets of divisions Sexual Reproduction and Genetics  Produces __________ __________ daughter cells that are ________ __________ 10.1 Meiosis  Results in genetic __________ Chapter 10

21. Other Concepts in Sexual Reproduction  __________- the joining of a sperm & egg to form a fertilized egg cell called a __________.

22. Other Concepts in Sexual Reproduction __________ in Plants - when pollen grains (______ ______) from a seed plant land on the female reproductive structure of the plant. This leads to __________ & __________ formation. This process is __________ by wind & animals

23. Other Concepts in Sexual Reproduction  __________ - A process in which two cells (__________ or __________) connect to each other and exchange genetic information – thereby increasing genetic variation.

24. Sexual Reproduction and Genetics Sexual vs. Asexual Reproduction Asexual reproduction  The organism inherits all of its chromosomes from a ________ parent.  The new individual is genetically __________to its parent. 10.1 Meiosis Chapter 10 Advantages: Doesn’t require a __________, _________works well in a ________ environment. Disadvantages: _____ genetic variation. A major environmental change can wipe out a species.

25. Sexual Reproduction and Genetics Sexual vs. Asexual Reproduction Sexual reproduction  The organism inherits __________ genetic info from each parent.  The new individual is genetically __________ from its parents. 10.1 Meiosis Chapter 10 Advantages: More genetic variation means possible __________ in a changing environment. Disadvantages: __________, ____ parents & mating required.