1. THE ANSWER TO YOUR QUESTION IS: YES!
Biology 101: Unit 5
First few days: Cell Cycle, Asexual vs Sexual Reproduction, Chromosome Number

2. GENETICS II: Cell Cycle Asexual vs Sexual Reproduction
Meiosis (friday)
Mon- finish meiosis- Reebops Lab
DNA Mutations
Genetics Disorders

3. IMPORTANT DATES TO KNOW:
Benchmark: USA TEST PREP: Thurs 10/17
MIDTERM: 10/18: will include all information up to this point on this test

4. Getting Started…
If you were the prosecutor in this criminal case, who would you want arrested? Why?
What is the DNA Technology that is used in this situation called?

5. How does cell division differ in uni and multicellular organisms?
Unicellular: reproduce by binary fission, budding, fragmentation= asexual reproduction
Multicellular: involves the production of sex cells

6. Compare internal/external fertilization
Fertilization- joining of sex cells
External fertilization- gametes are released into the environment
Internal fertilization- sperm are deposited inside female’s body

7. What are chromosomes? Carriers of genetic material found in nucleus
Made up of DNA

8. What is involved in Chromosome structure?
Chromosomes are made up of two chromatids which are held together with a centromere
Human chromosome number is 46 in body cells; 23 in sex cells

9. Compare haploid/diploid number
Haploid number- (n) “half-number” typically found in gametes only
Diploid number- (2n) “double-number” found in somatic cells (body cells)

10. How is gender determined in humans?
Females have XX as last set of chromosomes (sex chromosomes)
All eggs are X
Males have XY as last set of chromosomes
Half of sperm are X sperm; half are Y sperm
Males determine gender of offspring

11. Activity:
Chromosome Worksheet: Chromosome Number practice

12. What is the cell cycle? Sequence of growth and division in the cell
1. Interphase is the growth period where replication occurs
2. Mitosis

13. What is mitosis?
division of cells producing two cells with the same number of chromosomes
Ex: 46 chromosomes in human body cells, so ALL body cells should have 46

14. What is involved in Prophase?
Chromatin (normal form of DNA) coils into chromosomes
The nucleus disappears
Centrioles form and move to opposite poles of cell
Spindle fibers form from centrioles and begins to cross cell

15. What is involved in Metaphase?
Chromosomes line up in the middle of the cell
Spindle forms across the cell from centrioles

16. What is involved in Anaphase?
Spindle fibers begin to shorten
Chromosomes pulled apart
Move to opposite poles

17. What is involved in Telophase?
Chromosomes unwind into chromatin
Spindle fibers break down
Nucleolus and nuclei reform
Plasma membrane begins to pinch in

18. What is Cytokinesis? Division of cytoplasm
In animal cells: cell membrane continues to pinch in until two cells are formed
In plant cells: cell plate forms in center of cell and eventually splits cells
At the end of mitosis, two new cells are produced; called “daughter” cells

19. Thurs: 10/10 Quick Quiz 1
1. Which part of the cell cycle involves the copying of the DNA?
a. interphase b. mitosis
2. What is the division of the cytoplasm called?
a. cytolysis b. cytofission c. cytokinesis
Prophase B. Metaphase C. Anaphase D. Telophase
3. Which phase involves the splitting of the chromosomes?
4. Which phase involves the chromosomes lining up in the center of the cell?
5. Which phase involves the formation of chromosomes?
6. In which phase does a cell plate form in a plant cell?
7. The nucleus begins to disappear and spindle fibers begin to form across the cell?

20. Review of The Cell Cycle: Mitosis
Chromosome Structure/Number
Gender
Interphase
Mitosis- P-M-A-T-Cyto
Review Mitosis and Cancer Reading

21. Activity 1: Cell Cycle
Using supplies available in class, create a Cell Cycle Flipbook:
MUST INCLUDE:
ALL steps of the cell cycle: Interphase-Cytokinesis
Show LABELED diagrams and a description of what is happening in each stage

22. Activity 2: Mitosis Lab Onion Root Tip Lab Complete lab in lab area;
Use caution with microscope slides and the microscope

23. Asexual vs. Sexual Repoduction
Sexual Reproduction
Sperm and egg are produced & fused
Newly produced cells are genetically different from each other and the parent cell.
This creates genetic diversity
If it occurs in
human body cells- called meiosis
Single-celled organisms like bacteria or protists- called conjugation.
Asexual Reproduction
No sperm or egg are used
Newly produced cells are genetically identical to parent cell- clones
If it occurs in…
human body cells (like the skin)- called mitosis
single-celled organisms like bacteria or protists- called binary fission
simple animals (like sponge)- called budding

24. Homework: Thurs 10/10
HW: Why Sex is Good Case Study- ALL **If needed: Mitosis matching WS for practice with stages