Maxine

[]__**Summary:**__ Every cell in the human body has the same genome. Each DNA has 40,000 genes all coded to do different things. Out of those 40,000 genes researchers have discovered the functions of 5,000. When each genes function is know, scientists will know which genes cause diseases and why. Knowing which cause the diseases they will be able to cure or prevent diseases from taking effect on humans. They can analyze diseases and be able to diagnose individual medicine suited for a persons condition since everyone is different. __**Opinion:**__ Its an amazing accomplishment how researchers have discovered 5,000 of 40,000 gene functions. Sure there are a lot more to find out but there was no guide and instruction to figuring out those functions. Researchers used there own knowledge to determine the functions. When each gene has a known function there will be less suffering and it will be because of those researchers that figured the genome out for themselves. Its ridiculous how far we've come and it can only go farther, there is no turning back now. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - **Third Quarter Extra Credit!

Reproduction: Two Types: Asexual and Sexual Reproduction** -Asexual Reproduction: One Partner(Offspring is IDENTICAL) -Sexual Reproduction: Two Partners(Similar but NOT IDENTICAL offspring) Offspring receive half of their chromosomes from the female gamete(egg) and the other half from the male gamete(sperm) -Fertilization: Haploid + Haploid = Diploid(Sperm + Egg = Cell)
 * Binary Fission- Organism splits into 2 equal cells
 * Budding- Splitting off new individuals from existing ones
 * Vegetative Propagation-Piece of the vegetative part of a plant, root, stem, or leaf, produces an entirely new plant genetically identical to other.
 * Runners- Extensions along the ground give rise to new plant
 *    Rhizomes- Similar to runners but extensions are underground
 *    Tubers- Underground “swollen roots” that have all essential plant parts to develop their own
 *    Bulbs- Underground shoot that has modified leaves that are used for food storage
 * Grafting- Tissues of one plant are fused with those of another

Chromosome- A coiled and condensed strand of DNA Replicated chomosome consists of two “sister” chromatids Each chromatid is an exact copy of one another Sister chromatids are attached at the centromere Cell Division -Mitosis: Process in which a cell’s genetic material divides creating two complete sets of genetic material -Meiosis: Process in which a cell’s genetic material divides to produce sex cells or gametes(sperm and egg) Phases of Mitosis : (I) P M A T -Interphase -Prophase -Metaphase -Anaphase -Telaphase
 * Only occur in eukaryotic cells
 * Chromosomes(DNA) replicate to prepare for cell division(Not part of the mitotic phase)
 * Nuclear membrane disintegrates
 * Chromosomes condense and become visible
 * Spindle fibers(microtubles) begin to form in the cytoplasm, extending from one centriole to the other
 * Chromosomes line up single file on the equator
 * Centrioles are at the opposite poles of the cell
 * Spindle fibers run from centriole to the centromere of the chromosome
 * Centromeres of each chromosome separate and spindle fibers pull the sister chromosomes apart
 * Chromosomes cluster at the opposite ends of the cell
 * Coiled chromosomes unravel and return to their pre-cell division condition as long threadlike-strands
 * Nuclear membrane reforms

-Cytokinesis
 * Division of the cytoplasm
 * Animal Cells have clevage furrow that pinches inward
 * Plant cells have cell plate that forms down the middle

Stages of Meiosis: -Prophase I -Metaphase I -Anaphase I -Telophase & Cytokinesis I -Prophase II -Metaphase II -Anaphase II -Telophase & Cytokinesis II
 * Spindle fibers form, chromosomes condense, membrane disintegrates
 * Synapsis- homologous chromosomes pair up and form a tetrad(4)
 * Segments of chromosomes cross over at the chiasmata(GENETICALLY VARIED)
 * Chromosome tetrads line up at the equator
 * Spindle fibers attach to the tetrads
 * Homologous chromosomes seperate
 * Sister chromatids migrate together
 * Homologous pairs seperate with entire replicated chromosomes moving to opposite poles
 * Cytoplasm divides
 * 2 daughter cells are formed
 * Spindle fibers move toward the poles
 * Sister chromatids move toward the equator
 * Nuclear membrane disintegrates
 * Sister chromatids line up along equator
 * Spindle fibers attach to the centromere
 * Chromatids seperate
 * Cytoplasm divides
 * Nuclear membrane reforms
 * 4 daughter cells are produced

gametes are required (64 trillion combinations for zygote) [[image:c13x8meiosis-comparison.jpg]]
·