Meiosis Explained: How Egg and Sperm Cells Form with Half the Chromosomes

Pg. ,[object Object],[object Object],[object Object],[object Object]

Pg. ,[object Object],[object Object],[object Object],[object Object],[object Object]

M I T O S I S M E I O S I S I M E I O S I S II

Asexual vs. Sexual Reproduction ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

How many chromosomes in human cells? ,[object Object],[object Object],[object Object],2 sets of chromosomes 1 from mom & 1 from dad

How many chromosomes in human cells? ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],1 set of chromosomes

If egg and sperm had same number of chromosomes as other body cells . . . baby would have too many chromosomes! No Good! The Problem!

The Solution! Much Better! If egg and sperm had half the number of chromosomes than other body cells . . . baby would have just the right amount!

Meiosis ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],46 23

Meiosis allows sex cells to join to form a complete set of chromosomes/instructions to make a new organism. Copyright Pearson Prentice Hall Haploid gametes MEIOSIS Diploid zygote MITOSIS Diploid adult Not in notes

You tell me! ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],Not in notes

Meiosis is a special kind of cell division that halves the number of chromosomes in gametes. This insures that the correct number of chromosomes are passed on. Copyright Pearson Prentice Hall Not in notes

The goal is to make haploid sex cells Copyright Pearson Prentice Hall 1 st division 2 nd division Not in notes

Where does it happen? ,[object Object],[object Object]

Homologous Chromosomes Homologous chromosomes sister chromatids paternal sister chromatids maternal Tetrad

Homologous Chromosomes ,[object Object],[object Object],[object Object]

Homologous Chromosomes Paternal Maternal eye color locus eye color locus hair color locus hair color locus

[object Object],[object Object],Copyright Pearson Prentice Hall

Gametogenesis ,[object Object]

Gametogenesis ,[object Object],Meiosis I Meiosis II

Remember, humans have 23 pairs of chromosomes……………. ,[object Object],Copyright Pearson Prentice Hall gene for eye color gene for hair color

Phases of Meiosis ,[object Object],Copyright Pearson Prentice Hall Prophase I Metaphase I Anaphase I Telophase I and Cytokinesis Interphase I ,[object Object]

Phases of Meiosis ,[object Object],Copyright Pearson Prentice Hall Interphase I

Phases of Meiosis ,[object Object],[object Object],Copyright Pearson Prentice Hall MEIOSIS I Prophase I

Phases of Meiosis ,[object Object],[object Object],Copyright Pearson Prentice Hall

[object Object],[object Object],[object Object],[object Object],[object Object],Copyright Pearson Prentice Hall

Phases of Meiosis ,[object Object],[object Object],Copyright Pearson Prentice Hall MEIOSIS I Metaphase I

Phases of Meiosis ,[object Object],[object Object],Copyright Pearson Prentice Hall MEIOSIS I Anaphase I

Phases of Meiosis ,[object Object],[object Object],[object Object],Copyright Pearson Prentice Hall MEIOSIS I Telophase I and Cytokinesis

Phases of Meiosis ,[object Object],[object Object],[object Object],[object Object],Copyright Pearson Prentice Hall

Phases of Meiosis ,[object Object],Copyright Pearson Prentice Hall Telophase II and Cytokinesis Prophase II Metaphase II Anaphase II Telophase I and Cytokinesis I Meiosis II

Phases of Meiosis ,[object Object],Copyright Pearson Prentice Hall MEIOSIS II Prophase II

Phases of Meiosis ,[object Object],Copyright Pearson Prentice Hall MEIOSIS II Metaphase II

Phases of Meiosis ,[object Object],Copyright Pearson Prentice Hall MEIOSIS II Anaphase II

Phases of Meiosis ,[object Object],Copyright Pearson Prentice Hall MEIOSIS II Telophase II and Cytokinesis

Gamete Formation ,[object Object],[object Object],Copyright Pearson Prentice Hall

Gamete Formation ,[object Object],Copyright Pearson Prentice Hall

Interphase I ,[object Object],[object Object],[object Object]

Meiosis I ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],Prophase I Metaphase I Anaphase I Telophase I & Cytokinesis

Prophase I ,[object Object],[object Object],[object Object]

Prophase I - Synapsis Homologous chromosomes sister chromatids paternal sister chromatids maternal Tetrad

Prophase I centrioles spindle fiber spindle fibers

Crossing Over ,[object Object],[object Object],[object Object]

Crossing Over - variation variation nonsister chromatids chiasmata: site of crossing over Tetrad

Metaphase I ,[object Object],[object Object],[object Object],[object Object],[object Object]

Metaphase I metaphase plate OR metaphase plate

Anaphase I ,[object Object],[object Object]

Telophase I ,[object Object],[object Object]

Meiosis II ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Prophase II ,[object Object],[object Object]

Metaphase II ,[object Object],[object Object]

Metaphase II metaphase plate metaphase plate

Telophase II ,[object Object],[object Object],[object Object],[object Object]

Mitosis vs. Meiosis ,[object Object],[object Object],Diploid (2n) Parent Cells Replication of Chromosomes – double the # End of Mitosis & Meiosis I Results in 2 diploid (2n) daughter cells End of Meiosis II Results in 4 haploid (n) daughter cells

Pg. 143 Meiosis Vocab Word Description Picture Homologous chromosomes Tetrads Crossing over Haploid Diploid Locus Spermatogenesis Oogenesis

Meiosis Explained: How Egg and Sperm Cells Form with Half the Chromosomes

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Viewers also liked

Viewers also liked (8)

Similar to Meiosis Explained: How Egg and Sperm Cells Form with Half the Chromosomes

Similar to Meiosis Explained: How Egg and Sperm Cells Form with Half the Chromosomes (20)

Recently uploaded

Recently uploaded (20)

Meiosis Explained: How Egg and Sperm Cells Form with Half the Chromosomes