Presentation on theme: "Ch 7-1 Cellular Reproduction"— Presentation transcript:
1 Ch 7-1 Cellular Reproduction Interphase & Mitosis make up Cell Cycle (pg 174)The mitotic (M) phase of the cell cycle alternateswith the much longer interphase.The M phase includes mitosisand cytokinesis.Interphase accounts for 90% of the cell cycle.
2 Terms for the hereditary material (DNA) found in the nucleus.Chromatin—dense mass of material within thenucleus; composed of individual chromosomesChromosomes—structure that carries the genes;composed of protein & DNAChromatid—each individual strand of the doublestranded chromosome resulting from replication inProphase.Centromere—point at which sister chromatids areattached*DNA, Protein spool, Chromatin, & Chromosomes(Illustrations on pg 173)
3 The Cell Cycle Interphase—(resting stage) Not a part of mitosis Cell grows & carries on all life activitiesDNA & Chromosomes replicate; producing a 2nd set of chromosomes.Interphase has three subphases:the G1 phase (“first gap”) centered on growth,the S phase (“synthesis”) when the chromosomes are copied,the G2 phase (“second gap”) where the cell completes preparations for cell division,
4 There are four stages of Mitosis! Mitosis (M)—the cell divides thru the process by which chromosomes are duplicated & distributed to daughter nuclei; each daughter nucleus carries the same set of genetic information as the parent nucleus.There are four stages of Mitosis!ProphaseMetaphaseAnaphaseTelophase
5 Prophase Chromosomes shorten & thicken becoming visible Spindle fibers & asters formCentrioles move towards opposite polesBy the end, the nucleus & nucleolus have completely disappeared
6 MetaphasePaired chromatids (chromosomes) are lined up at the equator.Microtubules are attached at the centromere.AnaphaseCentromere splits & the two sister chromatidsseparate from one another & start movingtowards opposite poles…or sides of the cell.
7 TelophaseCytoplasm begins pinching in towards the center of the cell…(cytokinesis)Spindle fibers & asters disappearTwo new nuclei are formedChromosomes become a mass of chromatin againThe two daughter cells separate into two individual cellsAnimal Cell—pinching in a cell membrane to separate the two cellsPlant Cell—a cell plate forms which will eventually become the cell wall…also they go thru mitosis without the centrioles.