- Slides: 13
Mitosis & the Cell Cycle
Cell Growth & Development Are cells of organisms the same size? Do your cells get bigger as you grow, or do you just produce more cells? n When talking about Cell Size…… Smaller is Better! n The larger a cell becomes, the more demands the cell places on its DNA, and the harder it is to supply with nutrients. n
Cell Division Before a cell becomes to large, a growing cell will divide. n Cell division is the process by which a Single cell divides into 2 Daughter cells. n Cell Division = the series of events that cells go through as they grow and divide. n
Chromosomes n n n Chromosomes= are composed of DNAWhich carries the cell’s coded genetic information. Humans have 46 chromosomes(23 pairs). The chromosomes consist of two identical sister chromatids.
Two Major Types of Cell Division n Mitosis- Somatic cells (Body Cells) n n Diploid 2 N Meiosis- Sex cells/ Gametes n Haploid 1 N
Mitosis is the process by which the genetic information is replicated and distributed to daughter cells. n 2 diploid(2 N) daughter cells are produced from 1 diploid (2 N) parent cell. n The Daughter cells are genetically identical to the parent cells. n There are 4 major stages to mitosis, Not including interphase. n
Interphase n Interphase= The cell spends most of its life here; not part of the actual reproduction. NOT PART OF MITOSIS. Cell grows and replicates its DNA and centriole n Nuclear membrane is visible n Nucleus, Nucleoli, and chromatin can be seen. n
Prophase n Prophase: first phase of Mitosis n n Nuclear membrane breaks down Chromosomes become visible n Centrioles separate n Spindle forms
Metaphase n Metaphase: Second part of Mitosis n n Chromosomes attach to spindle Chromosomes line up across the MIDDLE of the cell
Anaphase n Anaphase: Third step in Mitosis n The sister chromatids separate and move apart towards opposite poles
Telophase n Telophase: Fourth stage of Mitosis n n n Chromosomes gather at opposite ends of the cell The nuclear membrane begins to form and enclose the chromosomes Cell membrane begins to move inwards
Cytokinesis n n n Cytokinesis: Final stage in cellular division Not Mitosis Works with telophase n n The cytoplasm divides completely in half. 2 daughter cells with identical genetic information are produced.