1. CCR Biology DSL
List 5 of your genetic traits you want to pass on to your children. Why those specific traits?

2. CCR Biology Agenda DSL Chromosome and Meiosis PowerPoint
Meiosis Review Worksheet – Due Monday

3. CCR Biology Objectives
I can compare mitosis and meiosis
I can model the phases of meiosis

4. Chromosomes and Meiosis Genetics LT1
Unit 5: Genetics
LT 1: Chromosomes and Meiosis

5. If stretched and laid end to end, the DNA in just one of your cells would be about 3 meters (10 feet) long. How does it fit inside the nucleus of a microscopic cell?

6. Condensing our DNA A chromosome is: thread of DNA and proteins
in nucleus of eukaryotic cells
consists of genes and regulatory information.

7. Chromosome Structure Pg. 139
DNA condenses tightly during the early stages of mitosis
Stage 1: DNA double helix
Stage 2: DNA and histones
Stage 3: Chromatin
Stage 5: Condensed, duplicated chromosome
Stage 4: Supercoiled DNA

8. Region of chromosome that holds sister chromatids together
Two identical chromatids that make up 1 chromosome

9. Exploring your cells and chromosomes
You have many specialized cells in your body BUT they can be divided into 2 major groups:
Somatic (body) cells
Germ cells

10. Cell types Germ cells: Somatic (body) cells:
cells in reproductive organs, the ovaries or testes
Develop into gametes: sex cells – eggs in the female and sperm cells in the male
DNA in gametes IS passed on to children
Divide by MEIOSIS
Somatic (body) cells:
make up most of body tissue and organs
Ex: spleen, kidneys, and eyeballs
DNA in body cells is NOT passed on to offspring
Divide by MITOSIS

11. Counting Chromosomes
Each of your body cells contains a set of 46 chromosomes, which come in 23 pairs
23 from mom and 23 from dad
These cells are genetically
identical to each other unless
mutations occurred
Cells in your body differ because different genes are expressed … NOT because they have different genes

13. “Homologous pairs”
Each pair of chromosomes is referred to a homologous pair
Homologous chromosomes: 2 chromosomes – 1 from mom and 1 from dad – that have the same length and general appearance
Autosomes: chromosome pairs 1 – 22
Contain genes not directly related to sex or organism
Sex chromosomes: 23rd chromosome pair
Controls development of sexual characteristics
XX = Female XY = Male

14. TELOPHASE AND CYTOKINESIS
Mitosis Review
Occurs in somatic cells
Consists of 4 stages
Produces 2 genetically identical daughter cells
PROPHASE
METAPHASE
ANAPHASE
TELOPHASE AND CYTOKINESIS

15. Meiosis Occurs in germ cells Consists of 8 stages
Produces 4 daughter germ cells with ½ the amount of DNA