6.1 Chromosomes and Meiosis Set up Cornell Notes on pg. 73 Topic: 6.1 Chromosomes and Meiosis Essential Question: Where are germ cells located in the human body? Draw a double-bubble map comparing and contrasting autosomes and sex chromosomes Don’t forget to add it to your T.O.Contents! 6.1 Chromosomes and Meiosis 2.1 Atoms, Ions, and Molecules Where are germ cells located in the human body? Draw a double-bubble map comparing and contrasting autosomes and sex chromosomes Key Concept: Gametes have half the number of chromosomes that body cells have

Sponge 1: Please correctly identify the phase of mitosis. 2 1 3 4

Telophase Anaphase Prophase Metaphase Sponge 1: Please correctly identify the phase of mitosis. Telophase Anaphase Metaphase Prophase

Mitosis and Meiosis Review (25 min.) Biology book Pg. 239 #3 – 13 write out the question and answers. Orange review booklets Mitosis and Meiosis Pg. 65 Part A definitions

KEY CONCEPT Gametes have half the number of chromosomes that body cells have.

Mom Dad Human body cells have 23 pairs of chromosomes and 46 total 2) Homologous pairs: each pair of chromosomes is called Homologous pairs and have copies of the same genes In each pair, one chromosome comes from each parent. *Homo= same

You have two types of specialized cells: Somatic cells Germ cells

Somatic cells- are body cells and make up most of your body tissues and organs. Examples Liver cells Lung cells Heart cells etc… Red blood cells skin cells bone cells intestinal cells

1) Autosomes: Chromosome pairs 1-22 are called autosomes Contain genes not directly related to your gender

Diploid Cells: Somatic (body) cells are Diploid (2n) cells have two copies of every chromosome (23 from mom, 23 from dad) for a total of 46 chromosomes *di= 2 n n 2n

Are sex cells: egg and sperm Gametes Are sex cells: egg and sperm Both have DNA that can be passed to offspring. Egg Sperm

Haploid cell: Gametes are Haploid (n) cells have one copy of every chromosome. Have 22 autosomes + 1 sex chromosome = 23 chromosomes each 23 23

XX XY XX= female XY= male 3) Sex chromosomes Pair #23=Sex chromosomes: X and Y determine gender Control the development of sexual characteristics XX= female XY= male XX XY

Where are sex cells located in the human body (2 places) Points to Ponder Where are sex cells located in the human body (2 places) Do you think that Y chromosomes contain genes that are critical for an organism’s survival? Explain.

Where are germ cells located in the human body (2 places) Points to Ponder Where are germ cells located in the human body (2 places) In the reproductive organs: The ovaries in women and the testes in men. 2. Do you think that Y chromosomes contain genes that are critical for an organism’s survival? Explain. No, a Y chromosome is not necessary for survival. Females do not have a Y chromosome, and they are able to survive.

Write out the question and answer choices. Review Part 2 (20 min.) Biology book Meiosis pg. 263 #1-9 Write out the questions and answer choices. Orange review booklet Part B and C pg. 65 Write out the question and answer choices.

Set up Cornell Notes on pg. 75 Topic: 6.1 Mitosis vs. Meiosis Essential Questions: Does mitosis or meiosis occur more frequently in your body? Explain. Draw a double-bubble map comparing and contrasting mitosis and meiosis Don’t forget to add it to your T.O.Contents! 6.1 Mitosis vs. Meiosis 2.1 Atoms, Ions, and Molecules Does mitosis or meiosis occur more frequently in your body? Explain. Draw a double-bubble map comparing and contrasting mitosis and meiosis

Two types of cell division: Mitosis Meiosis

Mitosis= makes more diploid cells. Produces genetically identical cells Results in diploid cells (46 chromosomes) Takes place throughout an organism’s lifetime Involved in asexual reproduction

*Draw on pg. 74 DNA replicates 2 identical daughter cells

Meiosis= makes haploid cells (23) from diploid cells. produces gametes (sperm/eggs) Produces genetically unique cells Takes place only at certain times in an organism’s life cycle Involved in sexual reproduction

(diploid- 46) *Draw on pg. 74 4 haploid (23) unique daughter cells

Please open your book to page 172 Please read the Genetic Data information Interpret the second bar graph and answer the 3 questions on the bottom of pg. 74 Title it “Genetic Data Chromosome Interpretation”

Diploid # of Chromosomes in Various Organisms Y- axis Dependent variable 10 210 20 40 40 49 55 X- axis Independent variable

King crab; fruit fly No. A porpoise is much bigger than a king crab, and has far less chromosomes. A potato is only 3 chromosomes off from human, and far smaller. Yes. Chromosomes need to be able to fit in the nucleus.

Homework: Due by Monday 11/05!!!! Make flashcards on index cards Front- word Back- Picture and description/definition 6.1 Somatic cells Gametes Homologous chromosomes Autosomes Sex chromosomes Sexual reproduction Fertilization Diploid Haploid Meiosis 6.4 Gene Allele Homozygous Heterozygous Genome Genotype Phenotype Dominant Recessive