L.+Meiosis+(13)

Meiosis Overview
toc Brightstorm Meiosis Overview media type="youtube" key="l-nufBO4zhs?version=3" height="315" width="560"

Another Overview of Meiosis media type="youtube" key="ijLc52LmFQg" height="315" width="560"

MEIOSIS CROSSWORD PUZZLE

Includes general terms and information, and you can solve it online. (Answer key on same page) [|Meiosis Crossword]

Quizlet Game on Overall Reproduction: [|Quizlet Reproduction/Genetics Game]

BLANK sexual vs. asexual venn diagram:



COMPLETED sexual vs. asexual venn diagram:



Target 2: Define homologous chromosomes and explain how chromosomes unite to form homologous pairs.
Homologous Chromosome Introduction media type="youtube" key="w6pZ4u8xxao" height="315" width="420"

In the human body, egg and sperm cells are the only haploid cells. Haploid cells are cells that have only one set of each chromosome. Haploid cells do not have homologous pairs because there is only one set of each chromosome, and pair implies two sets. Haploid cells are made by diploid cells (cells with two sets of each chromosome) that undergo meiosis. The human haploid number (n) is 23, which means human haploid cells have 23 chromosomes.

Target 4: Apply the term diploid to specific types of cells in the human body, the number of chromosomes, homologous pairs, and method of cell division.
In the human body, any cell that is not an egg cell or a sperm cell is known as a somatic cell. All somatic cells are diploid. Diploid cells are cells that have two sets of each chromosome (one from Mom and one from Dad). Homologous means that the genes in each of the chromosomes in the homologous pair can be found in the same locus (place where gene is found on chromosome). Homologous pairs are not identical (unless both of one’s parents gave identical DNA to their child, which would be weird and very very very unlikely). Homologous pairs have to have genes in the same locus but can have different alleles. The human diploid number (2n) is 46, which means that human diploid cells have 46 chromosomes. One set of chromosomes is homozygous in girls, but not in boys. This pair is known as the sex chromosomes and are labeled X and Y. Boys have an X and a Y chromosome, while girls have two X chromosomes

Target 5: Relate karyotypes to the cell cycle, homologous chromosomes, sister chromatids, gender, and their diagnostic capabilities.
Video about Karyotypes media type="youtube" key="q8errsrd4FE?version=3" height="315" width="560"

**Karyotypes**

Definition: Photographed, stained human chromosomes present at metaphase.

Use the following terms to fill out the blanks in the outline: sex chromosomes, Down Syndrome, autosomes, homologous chromosomes, X, Y, XX, XY. Terms may be used once, multiple times, or not at all.


 * The two chromosomes in a pair are called [1].
 * Each homologous chromosome is made up of [2].
 * Chromosome pairs 1-22 are called [3].
 * Remaining two chromosomes are called [4] because they determine an individual's sex.
 * Females have a pair of [5] chromosomes ([6])
 * Males have one [7] and one [8] chromosome ([9])
 * Used to screen for abnormal number of chromosomes or defective chromosomes associated with certain congenital disorders such as [10].


 * Answers (Highlight to see):** [1] Homologous Chromosomes, [2] Sister Chromatids, [3] Autosomes, [4] Sex Chromosomes, [5] X, [6] XX, [7] X, [8] Y, [9] XY, [10] Down Syndrome

1) Identify the Different types of Karyotypes Below:







2) How many pairs of homologous chromosomes do humans have?

a) 46

b) 23

c) 22

c) 44

3) What is the difference between a male karyotype and a female karyotype?

4) What is the difference between a normal karyotype and a Down Syndrome karyotype?

5) Label the pair of chromosomes on the left side of the following diagram for: Pair of Homologous Chromosomes, Centromere, Sister Chromatids, and Metaphase Chromosome.




 * Answers (highlight to see):**

1) Normal Male, Normal Female, Down Syndrome Male

2) b, 23

3) Male karyotype has both an X and a Y while the female karyotype has two X's.

4) Normal karyotype has a pair of homologous chromosome 21 while a Down Syndrome karyotype has three.

5)



Target 6: Describe the number of homologous chromosomes and sister chromatids in a human diploid cell in G1 and after the S phase of the cell cycle for both a human male and female.
Target 6 in a nutshell: After S phase: Homologous chromosome number stays same. Chromosomes are now made up of sister chromatids.

Target 7: Distinguish between events and characteristics of meiosis I & meiosis II including crossing over and tetrads.
Meiosis I and Meiosis II Video

media type="youtube" key="WSM-iH2wA4s" height="315" width="560"

[|Quizlet on Meiosis I and Meiosis II]



Target 8: Compare and contrast meiosis and mitosis.
Side by side animation and explanation of meiosis vs. mitosis - click on pink link below the text: [|Meiosis vs. Mitosis Animation]

McGraw Hill Animation and Quiz: [|Meiosis vs. Mitosis McGraw Hill]

Mindbites Comparison of Meiosis and Mitosis: media type="youtube" key="_IzfJSxa-uA" height="315" width="420" [|Quiz on Meiosis vs. Mitosis]

Meiosis Stages Picture Quiz: media type="custom" key="11983121"

Diagram Showing Side-by-Side Differences:

Target 9: Describe three mechanisms by which meiosis (and sexual reproduction) produce genetic variation.
Crossing Over Animation Diagram Showing the Process of **Crossing Over** Diagram Showing **Independent Assortment** **of Chromosome**

How does independent assortment of chromosomes produce genetic variation?

How does crossing over produce genetic variation?

How does random fertilization produce genetic variation?


 * Answers:**