Monday 11/9/2015 Agenda: Cell Cycle and Division! Activity: Finish Mitosis Packet Activity: Cell Cycle Quest!! Homework: No Homework Tonight! https://www.youtube.com/watch?v=ZEwddr9ho-4

Tuesday 11/10/2015 Agenda: Cell Cycle and Division! Activity: Meiosis Reading Guide Homework: Meiosis Reading Guide due Thursday/Friday 11/12-11/13/2015 for 40 Points NO SCHOOL ON WEDNESDAY!

Meiosis Reading Guide You are to annotate each paragraph 4 times (there are 4 total paragraphs) Answer questions 1-18 on the worksheet This is due TODAY for 40 Points!!

Thursday/Friday 11/12-11/13/2015 Agenda: Cell Cycle and Division! Notes: Meiosis and Meiosis Terminology Activity: Meiosis Foldable Activity: Amoeba Sisters with Worksheet Homework: No Homework!

Q2 WK3 D2 MEIOSIS

One parent cell produces four daughter cells. Meiosis Meiosis is the type of cell division by which germ cells (eggs and sperm) are produced. One parent cell produces four daughter cells. Daughter cells have half the number of chromosomes found in the parent cell

There are 2 parts to Meiosis: During meiosis, DNA replicates once, but the nucleus divides twice. There are 2 parts to Meiosis: Meiosis 1 Meiosis 2 The 4 new daughter cells have variation of the parent DNA; this is genetic variation

Meiosis Terminology Karyotype: Arranging of chromosomes from largest to smallest; pairing up the homologous chromosomes Autosomes: All non-sex chromosomes; (#1-22 for humans) Sex Chromosomes: Chromosomes that determine the sex of an organism (#23 for humans) Set (n): # of different chromosomes. REMEMBER: Haploid = 1set, Diploid= 2 sets

Karyotype of a human Is this person male or female? How many sex chromosomes are present? How many autosome chromosomes are present? How many homologous pairs of chromosomes are present?

Background on Meiosis Meiosis involves 2 divisions of the nucleus Meiosis STARTS with HOMOLOGOUS CHROMOSOMES Homologous Chromosomes: They are similar in shape, size & genetic content

Meiosis 1: 1st Division of Meiosis Prophase I: Chromosomes condense, nuclear envelope breaks, homologous chromosomes pair at ends. ***Cross-Over: Part of chromatid on 1 homologous chromosome exchanges with the other chromosome*** This is Genetic variation DRAW ME 

Meiosis 1: 1st Division of Meiosis Metaphase I: Homologous chromosomes move to center of the cell by the spindle fibers. Anaphase I: Homologous chromosomes separate and move to opposite poles, BUT sister chromatids stay together. A set of chromosomes moves to each pole Telophase I: The spindle fibers disappear, cells begin to cleave; still, two sets of chromosomes are at opposite poles

Meiosis 1

End of Meiosis I Once Meiosis I is complete, cytokinesis occurs and the cell splits into 2 haploid cells. These 2 cells enter Meiosis II

Meiosis II Prophase II: A new spindle forms around the chromosomes (no longer HOMOLOGOUS CHROMOSOMES) Metaphase II: Chromosomes line up at center & spindle fibers attach to centromere Anaphase II: Centromeres split, chromatids move to opposite poles of cell Telophase II: Nuclear envelope forms around each set of chromosomes & spindles retracts, cell begins cytokinesis

Result of Meiosis II 4 HAPLOID cells form as a result of Meiosis II Haploid = cell containing 1 set of chromosomes

Meiosis II: 2nd division of Meiosis

Prophase II http://everyschool.org/u/logan/cellreproductionx/rogersa/research/meiosis.html

Metaphase II http://everyschool.org/u/logan/cellreproductionx/rogersa/research/meiosis.html

Telophase II http://everyschool.org/u/logan/cellreproductionx/rogersa/research/meiosis.html

Differences in Mitosis & Meiosis Asexual Cell divides once Two daughter cells form Genetic informationS is identical Meiosis Sexual Cell divides twice Four haploid daughter cells form Genetic information is different