Review terms:
MPF
Cyclin
Phosphorylation
G1 checkpoint
Protein kinase
Cyclin-dependent kinase
Cell cycle checkpoints
G2 checkpoint
Metaphase checkpoint
P53
Tumor
Malignant tumors
Cancer
Apoptosis
Benign tumors
Metastasis
Rb proteins Growth factors
1. Have students write own definitions of highlighted terms and then go over them
-Cancer: out of control cell division. All cancers arise from cells in which cell-cycle checkpoints (G1 especially) have failed.
-P53: a protein that pauses the cell cycle or initiates apoptosis. If this protein is mutated cancer may occur.
-Apoptosis: program cell death
-Tumor: forms when one or more cells in a multicellular organism begins to divide in an uncontrollable fashion
Meiosis Chapter. 13
3. Worksheet: have them work through this however you feel comfortable. I will post the answers the next day
1. Human have 46 chromosomes in every cell except their gametes. a. Define what a karyotype is
Every organisms characteristic number and type of chromosomes b. What are sex chromosomes and how many are in every human somatic cell
The chromosomes that determine the sex of the individuals in some species. 1 pair. c. What are autosomes and how many are in every human somatic cell
All chromosomes except for the sex chromosomes. 22 pairs.

2. Meiosis occurs in two steps, meiosis I and meiosis II a. What is the ploidy of a cell before and after meiosis I
Before-diploid
After-haploid
*The homologs in each chromosome pair separate and go to different daughter cells b. What is the result of meiosis II
The sister chromatids of each chromosome separate and go to different daughter cells. Creating 4 haploid daughter cells. c. Diagram the process of meiosis I and meiosis II

3. The phases of meiosis a. What are the 5 phases of meiosis I and describe them as best as you can
1. Prophase I-homolog pairs come together in a pairing process called synapsis resulting in a tetrad, consisting of two homologs
2. Late prophase I-the non-sister chromatids being to separate and exchange or cross over between homologous non-sister chromatids.
3. Metaphase I-the tetrads line up at the metaphase plate
4. Anaphase I-the paired homologs separate and begin to migrate to opposite poles of the cell
5. Telophase I-the homologs finish migrating to the poles of the cell, and then the cell divides in the process of cytokinesis b. What are the 4 phases of meiosis II and describe them as best as you can
1. Prophase II-spindle apparatus forms, where one spindle fiber attaches to the centromere of each sister chromatid
2. Metaphase II-replicated chromosomes line up at the metaphase plate
3. Anaphase II-sister chromatids separate, the resulting daughter chromosomes begin moving to opposite sides of the cell
4. Telophase II-chromosomes arrive at opposite sides of the cell, the nuclear envelope forms around each haploid set of chromosomes, and each cell undergoes cytokinesis.