1. Question of the Day
3-7
When are sister chromatids formed? When are they separated? When are homologous pairs separated?

2. Question of the Day
3-8
What is cancer?
What causes cancer?

3. Today How Cancer Grows Quiz make ups
3-7
How Cancer Grows
Quiz make ups
Read Section 8.3 in the Owl Book and answer #s 1-6 on page 156

4. Question of the Day
3-9
What is a haploid cell (there are multiple correct answers)?

5. Question of the Day 1. What are the four stages of mitosis in order?
3-10
1. What are the four stages of mitosis in order?

6. Announcement
3-10
Plan for the Unit # 6 Test at the end of next week (Thursday 3-17 or Friday 3-18)

7. Control of Cell Division
Cell division in eukaryotes is controlled by many proteins.
Contact Inhibition = when normal cells come in contact with one another, growth stops

8. Cancer
Cancer may result if cells do not respond to proteins and/or contact inhibition.
Contact Inhibition -
Cancer cells do not stop dividing when they come in contact.

9. Cancer = uncontrolled cell growth
causes = mutated DNA (genetic or environmental)

10. Mitosis vs. Meiosis
 Mitosis produces 2 daughter cells while meiosis produces 4 daughter cells
 Mitosis produces diploid cells while meiosis produces haploid cells

11. Mitosis Review
Genetically – how similar are the daughter cells in mitosis?
They are identical
When is the DNA copied for the new cell?
S phase of interphase
What are two things make up chromosomes?
DNA and histones (protein)
What is the middle part of the chromosome?
Centromere
What gets separated during mitosis?
Sister chromatids NOT homologous pairs

12. Meiosis Objectives
Compare the end products of meiosis with those of mitosis.
Summarize the events of meiosis I.
Explain crossing-over and how it contributes to the production of unique individuals.
Summarize the events of meiosis II.
Compare spermatogenesis and oogenesis.
Define sexual reproduction. 12

13. Assignment
#s 1-6 on page 156 – Owl Book

14. Poster Contest Due Friday 3-11 3-8
Topics:
The S-phase of Interphase Prophase
Metaphase Anaphase
Telophase Cytokinesis
The chromosome
Creativity
Slogan / Title
Aesthetically pleasing
Accurately descriptive and understandable
MAKE SURE YOU GET A CHECKLIST FOR YOUR TOPIC!!!

15. Important vocab. review
What does DIPLOID mean?
Cells having 2 homologous copies of each chromosome (homologous pairs)
What does HAPLOID mean?
Number of chromosomes in a sex cell (half the number in a diploid cell)
What are sister chromatids?
Identical copies of the same chromosome

16. Important vocab. review
What is are sister chromatids?
Identical copies of the same chromosome
When does the cell produce the copy of the chromatid?
S phase of interphase

17. Important vocab. review
What are homologous chromosomes?
Chromosomes that carry genes for same traits (though variation of the trait may differ)
Allele – variation of a trait
Trait = flower color
Alleles = genes for either white or purple flowers

18. Formation of Haploid Cells
Meiosis – the process of making sex cells.
makes sperm and eggs
Four new haploid cells result (gametes)
Meiosis is broken down into Meiosis I and Meiosis II. 18

19. Question of the Day
3-14
How is meiosis different from mitosis (there is more than one correct answer)?

20. Announcement
3-14
Plan for the Unit # 6 Test on Friday 3-18

21. Reviewing Objectives Describe the structure of a chromosome.
How is a prokaryotic chromosome different than a eukaryotic chromosome?
How many chromosomes do you have?
How are diploid and haploid cells different?

22. Reviewing Objectives cell division in prokaryotes = ???
What happens during interphase?
4 stages of mitosis in order = ???
How is cytokinesis in animal cells different from cytokinesis in plant cells?
How is cell division controlled? What happens if it is not?

23. Meiosis I:  crossing over takes place
 homologous chromosomes get separated
 2 new haploid cells result

24. Meiosis II:  sister chromatids get separated (like in mitosis)
 2 new haploid cells result from each of the cells from meiosis I (total 4 new cells)

25. During meiosis…
Synapsis – pairing of homologous chromosomes – this did not occur in mitosis

26. Formation of Haploid Cells
Crossing-over – when portions of homologous chromosomes exchange genes
Results in genetic recombination.
Genetic recombination –
Regrouping of genes in an offspring that results in a genetic makeup that is different from the parents 26

27. Crossing Over

28. Crossing Over

29. Types of Reproduction
Asexual Reproduction = genes identical to parents
PRO:
Offspring well adapted to survival
Need only one parent
Fast
CON:
If susceptible to a disease, may kill off the entire population (b/c all genes are the same)

30. Why is genetic recombination important?
Sexual Reproduction
PRO:
Leads to genetic diversity from parents
Not all members will die from a disease (leads to species evolution)
CON:
Need two parents
Takes longer

31. Poster Contest Due Friday 3-14 3-14
Topics:
The S-phase of Interphase Prophase
Metaphase Anaphase
Telophase Cytokinesis
The chromosome
Creativity
Slogan / Title
Aesthetically pleasing
Accurately descriptive and understandable
MAKE SURE YOU GET A CHECKLIST FOR YOUR TOPIC!!!

32. Error in Meiosis
Nondisjunction - when a set of homologous chromosomes do not separate
Means "not coming apart"
Results in gametes with incorrect chromosome #