Cell Reproduction Page #1 Warm Up Where are your genes located?
http://people.na.infn.it/~nicodem/research/cell_genes.jpg
DURING MOST OF THE CELL S LIFE, DNA FORMS A TANGLED MASS CALLED CHROMATIN. CHROMATIN LOOKS LIKE A PLATE OF SPAGHETTI. RIGHT BEFORE A CELL DIVIDES, THE CHROMATIN FORMS INTO CHROMOSOMES (X- SHAPED).
CHROMATIN CHROMOSOMES MOST OF THE TIME ONCE IN A WHILE
Cell Division Chromosomes = Tightly coiled, rod-shaped DNA Chromosomes are made of chromatin Human body produces 2 trillion cells per day & 25 million per second Cells are formed by cell division of older cells 1. When a cell divides, DNA is first copied & then distributed 2. Each cell ends up with a complete set of DNA
Chromosome Number Each human somatic cell has 2 copies of 23 different chromosomes Total 46 Somatic = any cell that is NOT a sex cell (also called body cells or autosomes)
Sets of Chromosomes Each pair is made up of 2 homologous chromosomes Homologous chromosomes = chromosomes that are similar in size, shape, & genetic content Each homologue comes from one of the parents One from mom One from dad
Cells Can Be Diploid or Haploid Diploid = a cell that contains 2 sets of chromosomes (2n) Haploid (monoploid) = a cell that contains only 1 set of chromosomes (1n or n)
Chromosomes Determine Your Gender Humans have 23 pairs of chromosomes 22 pairs are autosomes (chromosomes NOT directly involved in determining sex) 1 pair are sex chromosomes (contain genes that WILL determine the sex) X & Y chromosomes
X & Y Chromosomes Male = XY Female = XX Male (dad) can donate an X or a Y to offspring Female (mom) can ONLY donate an X So-Which parent determines the sex of the baby?
MALE XY
Gametes Gametes are reproductive cells Males = sperm (n = 23) Female = egg (n = 23) Combine in fertilization to make a: Zygote (n = 46)
Haploid VS Diploid Page #2
Haploid and Diploid Understanding the concepts of Haploid and Diploid
Introducing Vocabulary Diploid= DIH ployd Haploid= HA ployd
Haploid and Diploid Let s take a look at the terms first. Diploid= Di Ploid Di means two
Haploid and Diploid Let s take a look at the terms first. Haploid= Ha Ploid think HAlf haploid is half of diploid.
Haploid and Diploid Review Diploid means Half Two
Haploid and Diploid Review Haploid means Half Two
GOOD JOB!!! You re on the way!!!
Introducing Vocabulary Gamete= GA - meat Somatic= So-MA-tik
Haploid and Diploid A Gamete is a generic term for a sex cell. An example would be a sperm or an egg.
Haploid and Diploid Gametes are Haploid in chromosome number.
Haploid and Diploid The number of chromosomes that a gamete would contain would be described as Haploid Diploid
Haploid and Diploid Somatic cells refers to every other cell in the body except gametes.
Haploid and Diploid Review Sperm or Egg = Gametes All Other cells = Somatic Cells
Haploid and Diploid Gamete or Somatic Cell? A Liver Cell Gamete Somatic Cell
Haploid and Diploid Gamete or Somatic Cell? A Sperm Cell Gamete Somatic Cell
Haploid and Diploid Gamete or Somatic Cell? A Brain Cell Gamete Somatic Cell
Haploid and Diploid Gamete or Somatic Cell? A Lung Cell Gamete Somatic Cell
Haploid and Diploid Gamete or Somatic Cell? An Egg Gamete Somatic Cell
Haploid and Diploid Gamete or Somatic Cell? A Skin Cell Gamete Somatic Cell
Keep Going!!! HAlf way There!!!
Haploid and Diploid Somatic Cells are Diploid in chromosome number.
Haploid and Diploid The number of chromosomes that a somatic cell would contain would be described as Haploid Diploid
Haploid and Diploid Review Gametes = haploid Somatic Cells = diploid
Haploid and Diploid Mathematically Speaking if haploid=n, then diploid=2n
Haploid and Diploid Mathematically Speaking or haploid is ½ of diploid or diploid is 2x haploid
Haploid and Diploid Review Sperm or Egg = Gametes=Haploid=n All Other Cells = Somatic Cells=Diploid=2n
Haploid and Diploid Humans have 46 chromosomes in their somatic cells. These cells are Haploid Diploid
Haploid and Diploid Humans have 23 chromosomes in their gametes. These cells are Haploid Diploid
Haploid and Diploid If humans diploid number = 46, what is the haploid number? 23 92
Haploid and Diploid If humans haploid number = 23, what is the diploid number? 46 92
Haploid and Diploid If chimps diploid number = 48, what is the haploid number? 24 96
Haploid and Diploid If chimps haploid number = 24, what is the diploid number? 48 96
Haploid and Diploid Review Again Sperm or Egg = Gametes=Haploid= n All Other Cells = Somatic Cells=Diploid= 2n
Haploid and Diploid If humans diploid number = 46, How many chromosomes in a liver cell? 23 46
Haploid and Diploid If humans diploid number = 46, How many chromosomes in a sperm cell? 23 46
Haploid and Diploid If humans diploid number = 46, How many chromosomes in a brain cell? 23 46
Haploid and Diploid If humans diploid number = 46, How many chromosomes in a lung cell? 23 46
Haploid and Diploid If humans diploid number = 46, How many chromosomes in an egg cell? 23 46
Haploid and Diploid If humans diploid number = 46, How many chromosomes in a skin cell? 23 46
Up so far!!! ALMOST THERE!!!
Haploid and Diploid Review Last Round Sperm or Egg = Gametes=Haploid= n All Other Cells = Somatic Cells=Diploid= 2n
Haploid and Diploid If chimp s haploid number = 24, How many chromosomes in a chimp s liver cell? 24 48
Haploid and Diploid If chimp s haploid number = 24, How many chromosomes in a chimp s egg cell? 24 48
Haploid and Diploid If Horse s diploid number = 64, How many chromosomes in a Horse s liver cell? 32 64
Haploid and Diploid If Alligators s diploid number = 32, How many chromosomes in a Alligators s liver cell? 32 64
Haploid and Diploid If Dog s diploid number = 78, How many chromosomes in a Dog s sperm cell? 39 78
http://www.goldiesroom.org/shockwave_p ages/reg-15-haplodvdiploid.htm
Mitosis Animation http://www.goldiesroom.org/shockwave_p ages/reg-14-tnm--celldivision.htm
Page #3 Karyotype Karyotype = a photo of the chromosomes in a dividing cell that shows the chromosomes arranged by size.
Karyotype cont d Each of an individual s 46 chromosomes has thousands of genes so the presence of all chromosomes is essential for normal functioning Humans who are missing a chromosome don t survive Humans with more than two copies of a chromosome, called trisomy, may survive but will not develop properly.
What is wrong?
The Cell Cycle Repeating sequence of cell growth and division during an organism s life 90% of cell life is spent in INTERPHASE Then it may go into MITOSIS & CYTOKINESIS
INTERPHASE (divided into mini-phases) G1(first growth) phase = Cell grows rapidly S (synthesis) phase = DNA copied G2 (2 nd growth) phase = Nucleus prepares to divide
http://publications.nigms.nih.gov/insidethecell/ch4_interphase_big.html
AFTER INTERPHASE Mitosis Cytokinesis http://www.cellsalive.com/cell_cycle.htm
Mitosis and Meiosis WARM UP Females are X Males are X Having 3 copies of a chromosome is called a
Mitosis and Meiosis Mitosis: -division of somatic (body) cells - results in two daughter cells that are identical Meiosis -division of gametes (sex cells)
Mitosis Interphase Prophase Metaphase Anaphase Telophase
The Cell Cycle is Carefully Controlled Key check points which feedback signals from the cell will delay the next step Controlled by proteins! 1. Cell Growth CHECKPOINT (G1) Start Nerve/muscle cells stop here 2. DNA Synthesis CHECKPOINT (G2) Enzymes 3. Mitosis CHECKPOINT Back to G1 phase
Page #4 When Control is Lost -- Cancer Cancer = Cell growth is uncontrolled - does not respond to control mechanisms. Causes: Mutations that cause over-production of growth molecules (accelerator) or by inactivating proteins that slow or stop the cell cycle (brakes) Tobacco and UV radiation linked to increased cancer risk.
Change in Chromosome Number Trisomy = humans with more than 2 copies of chromosomes improper development Karyotype = a photo of the chromosomes in a dividing cell. Disjunction = when egg/sperm cells form each chromosome and homologue separate sometimes one or more chromosomes fail to separate - unequal distribution. Down Syndrome - 3 copies of chromosome 21- NONDISJUNCTION
Change in Chromosome Structure Mutation A change in an organism s chromosomal structure. Deletion = piece of chromosome breaks off completely lacks of a set of genes fatal Duplication = chromosome fragment attaches to its homologous chromosome two copies of a gene set
Inversion = chromosome piece reattaches to original chromosome, but in reverse orientation. Translocation = chromosome piece reattaches to a nonhomologous chromosome.
Interphase Interesting things happen! 1. Cell preparing to divide 2. Genetic material doubles
Prophase Chromosome pair up! 1. Chromosomes thicken and shorten -become visible -2 chromatids joined by a centromere 2. Centrioles move to the opposite sides of the nucleus 3. Nucleolus disappears
Metaphase Chromosomes meet in the middle! 1. Chromosomes arrange at equator of cell 2. Become attached to spindle fibres by centromeres 3. Homologous chromosomes do not associate
Anaphase Chromosomes get pulled apart 1. Spindle fibres contract pulling chromatids to the opposite poles of the cell
Telophase Now there are almost two! 1. Chromosomes uncoil 2. Spindle fibres disintegrate 3. Centrioles replicate
Cell splits Cytokinesis
http://www.cellsalive.com/mitosis.h tm
Metaphase
Telophase
Prophase
Anaphase
http://www.youtube.com/watch? v=hv5kpidyc3m
Cell Reproduction Page #5 Warm Up List the stages of mitosis in order IPMAT
Meiosis Meiosis = Cell division that produces only haploid cells (half the number of chromosomes) Sex cells or gametes Spermatogenesis Oogenesis
Meiosis Occurs in Two Stages Meiosis I Meiosis II Follows the same order as MITOSIS, but it does it TWICE
Meiosis I Homologous chromosomes are separated into separate cells.
Interphase I Cell doubles its DNA and then doubles it again http://morgan.rutgers.edu/morganwebframes/level1/page7/meiosis1.html
Prophase I Chromosomes form Crossing over takes place http://morgan.rutgers.edu/morganwebframes/level1/page7/meiosis3.html
Crossing Over Exchanging corresponding segments of DNA Important because it gives a new combination of genes.
Crossing Over http://waynesword.palomar.edu/images/cross3.jpg
Metaphase I Chromosomes line up in the middle. http://morgan.rutgers.edu/morganwebframes/level1/page7/meiosis4.html
Anaphase I Chromosomes separate http://morgan.rutgers.edu/morganwebframes/level1/page7/meiosis5.html
Telophase I Cell begins to divide & 2 new cells form (cytokinesis) Each cell has chromosomes http://morgan.rutgers.edu/morganwebframes/level1/page7/meiosis6.html
Meiosis II Chromatids of each chromosome are separated into separate cells http://botit.botany.wisc.edu/images/130/meiosis/lilium_microsporogenesis/meiosis_ii.html
Prophase II Chromosomes form in both cells http://morgan.rutgers.edu/morganwebframes/level1/page7/meiosis7.html
Metaphase II Chromosomes line up along middle of cell http://morgan.rutgers.edu/morganwebframes/level1/page7/meiosis8.html
Anaphase II Chromosomes separate and are pulled apart into chromatids http://morgan.rutgers.edu/morganwebframes/level1/page7/meiosis9.html
http://www.scq.ubc.ca/filter/wp-content/uploads/2007/10/sister-chromatid.gif
Telophase II Chromatids gather at ends of cells Cytokinesis occurs (cell splits apart) http://morgan.rutgers.edu/morganwebframes/level1/page7/meiosis10.html
End Result of Meiosis & 4 new cells each with half as much genetic info as the parent Cytokinesis http://morgan.rutgers.edu/morganwebframes/level1/page7/meiosis10.html
http://www.cellsalive.com/meiosis.htm
Spermatogenesis http://www.soc.ucsb.edu/sexinfo/images/12-06-spermatogenesis.gif
Oogenesis http://img.sparknotes.com/content/testprep/bookimgs/sat2/biology/0003/oogenesis.gif