Lilliana

9C: Room 206 Front of Room Jason Amando Crystal Carla Jonathan Joe Marie Obayanna Kendra Lilliana Anthony Amanjot Asarel Karen Julian Marcus Jamesly Meryem Brunyr Rockens Jhon Christine Garlyn

Bio 9C: Friday, 3.11.11Title: Introduction to Meiosis & Genetic Inheritance • Homework: • Go to the Biology blog (phascience.wordpress.com) and do the note-taking assignment. • Then answer the questions on the back of assignment sheet (also on PowerPoint) • Finish the Karyotyping Activity & Questions if you didn’t finish it in class. • Do Now: • What is a chromosome and how does it relate to DNA? • Today’s Objectives: • Describe the difference between asexual and sexual reproduction • Explain how karyotypes are made and be able to identify homologous chromosomes in a human karyotype. • Differentiate between a male and female karyotype.

HUMAN GENETICS& MEIOSIS PHA: Biology 9 Moretti and Dickson

Asexual vs. Sexual Reproduction Asexual Reproduction • One parent • Parent and offspring are genetically identical (clones) • Reproduce using MITOSIS Sexual Reproduction • Two parents • Offspring are genetically different from parents • Reproduce using MEIOSIS (makes eggs and sperm) and FERTILIZATION (egg and sperm join) • Objectives for Class: • Describe the difference between asexual and sexual reproduction

Sexual reproduction cycle:

Human body cells contain… • Over 20,000 genes stored on 46 total chromosomes • 23 pairs ofhomologous chromosomes • 22 are same in males in females (1-22) • The 23rdpair is the sex-determining chromosomes • Females = X X • Males = X Y • Objectives for Class: • Explain how karyotypes are made and be able to identify homologous chromosomes in a human karyotype. • Differentiate between a male and female karyotype.

Karyotyping Activity – Part I Individual A Individual A • Circle 3 pairs of homologous chromosomes • Objectives for Class: • Explain how karyotypes are made and be able to identify homologous chromosomes in a human karyotype. • Differentiate between a male and female karyotype.

Bio 9C: Monday, 3.14.11Title: Meiosis & Genetic Inheritance – Vocab. Review • Homework: • Read Section 11.4 (pages 275-278). Address the following questions: • What is the purpose of meiosis? • How does the process accomplish this purpose? What are the major steps and the final result? • How does the process of meiosis create gametes that are different from each other? Name two ways. • Why does it matter that a person’s gametes are not all the same? • Do Now: • Clear desks for a quick quiz • Today’s Objectives: • Differentiate between mitosis and meiosis • Explain how meiosis produces 4 haploid sex cells (gametes) – eggs and sperm

Quick Genetics Vocabulary Quiz • Word Bank:Diploid, Haploid, Gametes, Meiosis, Alleles, Chromosome, Gene, Homologous Chromosomes • Match the above words with the definition. You will not use all of the above words • Egg or sperm cells used in sexual reproduction are called____? • A cell that contains TWO COPIES of every chromosome (in homologous pairs) is called ___? • A pair of chromosomes that contain the same genes but not necessarily the same alleles are called ______? • The process that separates homologous chromosomes into different haploid cells is called ____. • Different versions of a gene are called _____? • A cell that contains ONE COPY of every chromosome is called ___? • Are eggs and sperm are haploid or diploid? • A section of DNA that holds instructions for making one protein is called a _____?

Major Genetics Terms • Gene: • A section of DNA that holds instructions for making one protein • Ex: gene for hemoglobin protein • Alleles: • Different versions of a gene • Ex: normal hemoglobin allele vs. mutated hemoglobin allele • Chromosome: • A long strand of DNA, coiled and wrapped up, that contains many genes • Homologous Chromosomes: • A pair of chromosomes that contain the same genes but not necessarily the same alleles

Major Genetics Terms • Diploid: A cell that contains TWO COPIES of every chromosome (in homologous pairs) • All human body cells except gametes are diploid. • Haploid: A cell that contains ONE COPY of every chromosome • Gametes are haploid. • Gametes: Egg or sperm cells, used in sexual reproduction. • Contain HALF the number of chromosomes as all other body cells (they are haploid!) • Meiosis: The process of making gametes. • 1 Diploid cell  4 Haploid cells • Separates homologous chromosomes into different cells

Karyotyping Activity – Part I Individual A Individual A • Circle 3 pairs of homologous chromosomes • Objectives for Class: • Explain how karyotypes are made and be able to identify homologous chromosomes in a human karyotype. • Differentiate between a male and female karyotype.

Start: Diploid Cell (46 Chromosomes in Humans) Start: Diploid Cell (46 Chromosomes in Humans) Metaphase I: chromosomes line up with homologous pairs Metaphase: chromosomes line up single file End: 4 Haploid Cells (23 Chromosomes in Humans) Cells different from starting cell (half the # of chromosomes) Metaphase II: like mitosis End: 2 Diploid Cells (46 Chromosomes in Humans) Cells same as starting cell

Bio 9C: Tuesday, 3.15.11Title: Introduction to Meiosis & Genetic Inheritance • Homework: • No Homework • Do Now: • What are the differences between Meiosis and Mitosis? What are the similarities? • Today’s Objectives: • Differentiate between mitosis and meiosis • Explain how meiosis produces 4 haploid sex cells (gametes) – eggs and sperm • Describe the two ways meiosis creates genetic diversity between gametes

Quick Genetics Vocabulary Quiz • Word Bank:Diploid, Haploid, Gametes, Meiosis, Alleles, Chromosome, Gene, Homologous Chromosomes • Match the above words with the definition. You will not use all of the above words • Egg or sperm cells used in sexual reproduction are called____? • A cell that contains TWO COPIES of every chromosome (in homologous pairs) is called ___? • A pair of chromosomes that contain the same genes but not necessarily the same alleles are called ______? • The process that separates homologous chromosomes into different haploid cells is called ____. • Different versions of a gene are called _____? • A cell that contains ONE COPY of every chromosome is called ___? • Are eggs and sperm are haploid or diploid? • A section of DNA that holds instructions for making one protein is called a _____?

Studying Diagrams: • In your notebooks, respond to these questions: • What is the difference between Metaphase in Mitosis and Metaphase I in Meiosis? Why are the chromosomes aligned differently in both of these stages? • Are the cells diploid in Mitosis during this phase? Meiosis? Why? • What do you notice about the homologous chromosomes in Metaphase II of Meiosis? Why are the chromosomes aligned the way they are? • Are the cells in Metaphase II diploid or haploid? Why?

Bio 9C: Wednesday, 3.16.11Title: Meiosis Simulations • Homework: • Complete the Meiosis Pipecleaner Simulation Questions • Do Now: • What are the differences between Meiosis and Mitosis? What are the similarities? • Today’s Objectives: • Differentiate between mitosis and meiosis • Explain how meiosis produces 4 haploid sex cells (gametes) – eggs and sperm • Describe the two ways meiosis creates genetic diversity between gametes

Meiosis Simulation w/ Pipecleaners • Overview: • You will use pipecleaner “chromosomes” to simulate the process of meiosis. • Objectives: • By the end of this simulation activity, you should be able to… • Draw and describe the important steps of meiosis • Explain how the process of meiosis creates gametes with half the number of chromosomes as the original cell • Explain how meiosis generates genetic diversity between gametes

Bio 9C: Thursday, 3.17.11Title: Genetic Variation and Errors in Meiosis Double Block • Homework: • Complete Karyotyping II questions • Do Now: • What is the difference between Metaphase I in Meiosis and Metaphase in Mitosis? What impact does this have on how chromosomes divide? • Today’s Objectives: • Describe the two ways meiosis creates genetic diversity between gametes • Identify genetic disorders that result from mistakes during Meiosis

Summary of Meiosis • DNA is replicated once • Chromosomes are divided twice: • Meiosis I: Homologous chromosomes separate • Forms 2 haploid cells • Chromosomes still have sister chromatids • Meiosis II: Sister chromatids separate • Final result: 4 haploid gametes with HALF the number of chromosomes as the original cell Gametes • Objectives for Class: • Explain how meiosis produces 4 haploid sex cells (gametes) – eggs and sperm

Meiosis generates genetic diversity between gametes: Two Ways • Independent alignment of homologous pairs during Metaphase I. • A cell with 2 homologous pairs yields 4 possible gametes. • How many are possible with 23 homologous pairs?

Meiosis generates genetic diversity between gametes: Two Ways 2. Crossing over during Prophase I. • One sister chromatidtrades a section of DNA with its homologous partner. • Creates new combinations of alleles on chromosomes. • Can happen at multiple places along the chromosome, allowing for a nearly infinite number of different gametes.

Karyotyping Activity – Part II As you have learned, a karyotype is an enlarged photograph of a person’s chromosomes arranged so that the homologous chromosomes are next to each other. As we have also discussed, meiosis is the process that separates these homologous chromosomes into different sex cells called gametes. When meiosis works properly, each gamete will receive one copy of each type of chromosome (one chromosome 1, one chromosome 2, etc.). However, sometimes an error in meiosis occurs and gametes receive abnormal numbers of chromosomes. When these gametes (eggs or sperm) join with the gamete from another individual during fertilization, the result is a person with an abnormal numbers of chromosomes. In this activity, you will examine the karyotypes for a variety of different people to determine if the individual has the expected number of 46 total chromosomes. Analyze each karyotype by answering the questions for each one. If you determine that the individual has an abnormal number of chromosomes, determine the type of chromosome disorder the person has and describe it in the space provided. • Objectives for Class: • Explain how karyotypes are made and be able to identify homologous chromosomes in a human karyotype. • Identify genetic disorders that result from mistakes during Meiosis

Lilliana

Lilliana

Presentation Transcript

Lilliana Esquivel  Dana Huestis  Liz Sacks  Erin Sherwood  Bo Wang