Cell Division Flashcards
-Somatic cell division
-Somatic (soma=body) cells (body cells)
-Mitosis (DNA in nucleus is divided among the two daughter cells)
-One diploid (2N=diploid) parent cell two 2N (also diploid) daughter cells
-Reproductive cell division
-Germ cells
-Gametes (sperm, oocyte) and precursors
-Meiosis
-One 2N (diploid) parent cell four haploid (1N=haploid) cells (gametes)
Terms : Hide Images [1]
| 1022199730 | Interphase | -(Where G stands for growth) -G1 -S (DNA is replicating) -G2 | |
| 1022199731 | G1 phase | -Metabolic activity -Replication of organelles -Centrosome replication begins S phase (synthesis) -Replication of DNA -Double helix partially uncoils -Each strand serves as a template for the synthesis of a new complementary strand | |
| 1022199732 | G2 phase | -Metabolic activity -Cell growth -Centrosome replication is complete | |
| 1022199733 | Mitotic phase includes | -Mitosis -Division of nucleus (including chromosomes) between daughter cells -Cytokinesis -Division of cytoplasm (including organelles) between daughter cells | |
| 1022199734 | Mitosis | -A continuous process but is divided into four stages for convenience -Prophase -Metaphase -Anaphase -Telophase | |
| 1022199735 | Interphase | -Chromosomes and organelles have duplicated -Nucleus is very visible and you can see the DNA -Chromosomes in diffuse form (chromatin) -Nucleus envelope intact | |
| 1022199736 | Prophase | -Nuclear envelopes disintegrates -Chromosomes in condensed form (chromatid pairs) -At this point, DNA has been duplicated and exists as chromatid pairs -Homologous chromatids are joined by a centromere -Centrosomes begin to produce a mitotic spindle composed of microtubules | |
| 1022199737 | Metaphase | -Chromatid pairs line up along equator of the cell -Centromeres aligned at the center of the mitotic spindle (the line of chromatid pairs is also called the metaphase plate) | |
| 1022199738 | Anaphase | -Centromeres split -Members of chromatid pairs (chromosomes) move toward opposite poles of the cell -Microtubules of mitotic spindle pull on centromeres of the chromosomes -Notice V shape -Early anaphase they're getting slightly pulled, but then in late anaphase they're being pulled | |
| 1022199739 | Telophase | -Chromosomes reach opposite poles of the cell -New nuclear envelope forms -Cytokinesis involves formation of cleavage furrow (microfilaments arranged around center and pinch the separation). |