Cell Division Flashcards
Cell Cycle Stages(Mitosis)
Interphase
- G1 Phase
- S Phase
- G2 Phase
Mitosis
- Prophase
- Metaphase
- Anaphase
- Telophase
Cytokinesis
3 Functions of Cell Division
Growth - growth of organisms
Repair - repair if tissue and organisms
Maintenance - replace dead if dying cells
Occurrences in Interphase
Growth 1
- manor period of growth, cell synthesize new molecules
- centrosomes are duplicated
- needed to direct movement of chromosomes
Synthesis Phase
- DNA(in chromatin form) is replicated
- 2 copies of every chromosome
Growth 2 Phase
- the cell synthesizes more molecules prior to mitosis
Occurrences in Prophase
- Chromatins shorten and thicken into chromosomes
- Each chromosome = two copies of one chromosome
- sister chromatids are joined together at the centromere
- centrosomes separate and move to opposite poles and leave microtubules which will become spindle fibres
Occurrences in Metaphase
- The spindle fibers guide the chromosomes to the equator of the cell
- Centromeres are aligned across the middle of the cell
- Spindle fibers from opposite poles attach to the centromere of each centrosome
Occurrences in Anaphase
- The chromosomes divide
- Motor proteins pull on each side of centromere
- Centromere splits apart and sister chromatids separate from eachother
- Separated sister chromatids are now called chromosomes
- Spindle fibers shorten pulling the chromosomes to opposite poles
Occurrences in Telophase
- The seperated chromosomes reach opposite poles
- Chromosomes unwind into chromatin
- Spindle fibers break down
- Nuclear membrane forms around the nee sets of chromosomes
- A cleavage forms
Occurrences in Cytokinesis
- Division of cytoplasm
- 2 New daughter cells(genetically identical)
Cell Cycle Stages(Meiosis)
Interphase
- G1 Phase
- S Phase
- G2 Phase
Meiosis I
- Prophase I
- Metaphase I
- Anaphase I
- Telophase I
Cytokinesis 1
Meiosis II
- Prophase II
- Metaphase II
- Anaphase II
- Telophase II
Cytokinesis 2
Occurences in Prophase I
- Chromosomes start to shorten and thicken
- Each chromosome was replicated during interphase, and now consists of two sister chromatids joined at the centromere
Synapsis- Each pair of homologous chromosomes line up side by side
- Crossing over(exchange of genetic information)