1. Bellringer What is happening in metaphase?
What is happening in anaphase?
How many cells are created in mitosis? What about meiosis?
Where in the human body does meiosis occur?

2. Test on the 16th (B) and 13th (A)
Meiosis
Test on the 16th (B) and 13th (A)

3. Stages 2 divisions to make 4 genetically different cells from one cell
First Divisionmeiosis I
Prophase I
Metaphase I
Anaphase I
Telophase I
Cytokinesis I

4. Prophase II Metaphase II Anaphase II Telophase II Cytokenesis II
Second Division
Prophase II
Metaphase II
Anaphase II
Telophase II
Cytokenesis II

7. Meiosis I
The homologous chromosomes begin to pair up-called synapsis
The pairs in meiosis I are called tetrads
The goal of meiosis I is to break apart tetrads
Meiosis II
Chromatids separate and migrate to polls
Chromatids arrive at polls, and cell divides
The result is four cells with half the number of chromosomes as the starting cell

11. Animations
Mitosis animation
mitosis.htm
Meiosis animation
meiosis.htm

12. Make a Venn Diagram
Mitosis
Meiosis
Both

13. Characteristics of Meiosis

14. Vocabulary Somatic Cells “body cells” non-sex cells
Germ cells Cells in reproductive organs cells
Gamete sex cells (sperm and egg)
Autosomes non sex chromosomes (the other 22 pairs)
Sex chromosomes- chromosomes which determine male and female X and Y (one pair)

15. Genetic Recombination
Mixing of genetic information between chromosomes of the same organism or between two different organisms
Causes diversity in offspring
Can be done by man or natural
When done by man, called genetic engineering when scientists transplant genetic material from one organism to another.
When natural crossing over

16. Crossing Over
When a gene or piece of DNA switches places with a gene or piece of DNA from a homologous chromosome
In other words, material from each parent can be switched between homologous chromosomes
If this occurs, genetic information can be exchanged
Prophase I of Meiosis I
Increases genetic diversity

17. Crossing over

18. Independent Assortment
Alleles of different genes assort independently of one another during gamete formation
metaphase of meiosis I
the gamete can end up with any combination of paternal or maternal chromosomes
Increases genetic diversity
In humans there are 223 different combinations

19. Independent Assortment

20. Law of Segregation
when any individual produces gametes, the alleles separate so that each gamete receives only one copy.
A gamete will receive one allele or the other.
In meiosis the moms and dads chromosomes get separated and the alleles with the traits of a character are segregated into two different gametes.

22. Random Fertilization
Men produce millions of sperm, and each sperm has an equal chance of fertilizing the egg
Women produce multiple eggs per month, but only one is used for fertilization. The rest are used as polar bodies
Resulting is a randomly produced zygote with random alleles from each parent.

24. Haploid (n) Haploid a cell that has only one set of chromosomes
This means that the cell will have 23 chromosomes
Sex cells are haploid cells
A male haploid sperm cell and a female haploid egg cell will come together to make a diploid zygote (one celled embryo)

25. Diploid (2n)
Diploid a cell or organism that has two sets of chromosomes
Diploid cells have 46 chromosomes
One from mom and one from dad
Two haploid cells come together and make a diploid organism
A diploid cell would be your somatic cells. Which are…?

26. Spermatogenesis The process of creating sperm Male meiosis
Every one meiosis cycle produces 4 sperm
Males do this constantly with little regulation

28. Oogenesis Female meiosis Process of making egg cells
Only one egg cell per meiosis cycle
Only one meiosis cycle per month
The other four cells, called polar bodies, are going to become food for the potential fertilized egg
In other words, three out of the four cells do not become eggs, they become polar bodies
Ovum the mature egg once it has grown. It is ready to be fertilized by a sperm

30. Concept Four Square Draw a picture to represent the concept
Describe in your own words the major concept of choice
Draw a picture to represent the concept
Tell me how it is different than another concept we covered today
Why did we learn about the concept? (your answer can’t be because its on the test)
Concept