•79. DNA Notebook Check•80. Genetics Unit Cover – title & 5 colorful pictures•81. Reproduction•82. The Order of Mitosis•83. Mitosis Lab•84. Meiosis Notes•85. Comparing Meiosis vs. Mitosis•86. Cell Reproduction Review•87. Regulating the Cell Cycle•88. Why Variation Occurs•89. Cell Reproduction Crossword•90. Progress Report #5•91. Cell Reproduction Notebook Check

• Next class - Cell Reproduction Quiz• 2/27 thru 3/7 - Castle Learning Extra Credit• 3/1 & 3/2 – –Progress Reports due back signed, –Notebook check signatures (#79)–Notebook Checks for 79 – 91–CMS assessment

• 3/3 & 3/4 – Chapter 11 Reading Guide due• 3/8 TUESDAY 8 am - DNA OR Cell

Reproduction Quiz retakes• 3/11 - Honors Assignment Due• 3/16 & 17 - Vocabulary Quiz 7a (sept – toxico)

IMPORTANT DATES!!!

ASEXUAL SEXUAL

Reproduction#81

ASEXUAL REPRODUCTIONRequires only one parent/cellOffspring genetically identical to

parent cellTypes:

Fission/BuddingFragmentationRegeneration

Advantages: inability to move/mate, high production/low cost, very little change occurs

DEFINETHESE!

• Why do we need our somatic cells to reproduce?–Organisms grow because they have MORE cells– Tissue Repair

• Parent cell turns into 2 daughter cells

• DNA replicates and is evenly distributed to new cells• THE CELL CYCLE– Interphase: preparing for mitosis • cell growth and DNA and organelle replication occur

–Mitosis: NUCLEAR DIVISION, 4 stages: • prophase, metaphase, anaphase, telophase

– Cytokinesis: DIVISION OF CYTOPLASM• I put macaroni above the counter

CELL DIVISION a form of asexual reproduction

video

SEXUAL REPRODUCTION• Requires two parents/cells• Offspring has a mix of genes• GAMETES = sex cells (sperm, egg)–Contain only 23 chromosomes (SOMATIC cells

contain 46 chromosomes)• Sperm + Egg = ZYGOTE –(all living things start out as one cell)

• FERTILIZATION = when sperm & egg meet• MEIOSIS – how your body makes sperm cells

and eggs cells

THE ORDER OF MITOSIS•DNA replicates•Cell grows•Cell duplicates its organelles

METAPHASE

ANAPHASE

PROPHASE

CYTOKINESIS

INTERPHASE

TELOPHASE

• In plants• In animals

CYTOKINESIS

• Process of making sex cells (gametes)• Involves TWO cell divisions (meiosis I &

II)• Reduces the # of chromosomes in a cell• Makes HAPLOID cells(containing 23

chromosomes) = n• Somatic Cells = DIPLOID = containing

46 chromosomes = 2nEach chromosome has a “partner”

called a homologous chromosome (23 pairs)

These homologs contain the same “type” of information, but not identical

MEIOSIS #84

Homologous PairsHomologous pairs have

regions that code for the same genes (hair color)

Sister chromatids are exact replicas to each other

Mom donates B for brown hair Dad

donates b

for blonde

hair

• Spermatogenesis – creation of sperm cells through meiosis–Occurs in testes–Creates 4 sperm cells–Begins at puberty, ends at death–Takes 7 weeks to complete

• Oogenesis – creation of egg cells through meiosis–Occurs in ovaries–Creates 1 egg cell (matures monthly)

and 3 leftover cells–Begins before birth, ends menopause

video

1. Cells at the edges of injuries…2. When the healing process nears completion, those rapidly

dividing cells…3. Cyclins are a group of proteins that…4. Internal regulators are…5. External regulators are…6. Cell growth is regulated so carefully because…7. Cancer is…8. Cancer cells [do/do not] respond to the signals that

regulate the cell growth.9. Create a 3-step flowchart about how cancer forms.10.Why can cancer be considered a disease of the cell cycle?

Regulating the Cell Cycle #87

Pg. 250 in

text

1. Cells at the edges of injuries…2. When the healing process nears completion, those rapidly

dividing cells…3. Cyclins are a group of proteins that…4. Internal regulators are…5. External regulators are…6. Cell growth is regulated so carefully because…7. Cancer is…8. Cancer cells [do/do not] respond to the signals that

regulate the cell growth.9. Create a 3-step flowchart about how cancer forms.10.Why can cancer be considered a disease of the cell cycle?

Regulating the Cell Cycle #87

Pg. 250 in

text

Cancer forms when…

Cells do not

respond to

cyclins

These “cancer”

cells divide

uncontrollably and

create tumors

Cancer cells may

break loose from

those tumors

and disrupt normal

activities of the body

• Crossing Over during meiosis I – homologs swap genetic material

Why Variation Occurs #88

video

• Random assortment of chromosomes during meiosis– Gametes get different alleles of

genes• Gene Mutations• Fertilization (certain sperm + certain

egg)• Non-Disjunction…

• Non-Disjunction… chromosomes don’t separate properly

during meiosis (anaphase I) Trisomy = 3 chromosomes in pair

DISORDER

GENOTYPE

SYMPTOMS

Turner Syndrome

45 chromos,Missing sex chromos, X0

Female, sterile, short, thick neck

KlinefelterSyndrome

47 chromos,Extra sex

chrom, XXY

Male, sterile, tall, feminine shape, low testosterone

Down Syndrome

47 chromos,Trisomy 21,

XX or XY

Flat face, stout body, eye slant, mental disability

PatauSyndrome

47 chromosTrisomy 13,

XX or XY

90% die within 3 days, cleft lip,

polydactyl, severe mental

disability