CH 12 Cell Division Flashcards
Cell division purpose (x3)
- Growth
- Replacement
- Repair
Result of cell division by Mitosis
Genetically identical daughter cells
Animal Gametes
- Sperm cells
- Ova
Plant Gametes
- Pollen
- ovule
Non-Reproductive cells..
- Somatic Cells
- 2 sets of chromosomes (diploid)
- 2n
Reproductive cells…
- Gametes
- 1 pair of chromosomes (haploid)
- n
Chromatid
Chromosomes in prep for division
Narrow band in a chromosome
Centromere
Mitosis divides…
Division of sister chromatids
Cytokinesis Divides…
Division of the cytoplasm
Meiosis Yield…
- genetically non identical daughter cells;
1. 1 set of chromosomes
2. Haploid
3. n
3 Stages of Interphase
- G1 Phase (1st growth)
- S Stage (synthesis / DNA rep.)
- G2 Phase (2nd growth)
4, M Phase (mitosis phase)
Early Prophase
centrioles split and move to opposite poles
- microtubules form
ProMetaPhase (late P phase)
- Nuclear Envelope disappears
- Kinetochore formed
MetaPhase
- Sister chromatids line up @ centre (metaphase plate)
meta means…
Middle
Anaphase
- sister chromatids pulled apart by spindle fibers
- Now independent chromosomes
Ana means…
To break
Telophase
- Nuclear membrane BEGINS to reform
- Chromosomes begin to unwind
Tell means…
Across distance
Cytokinesis means…
cell movement
Cytokinesis
- animals; cleavage furrow forms, thins and breaks
- Plants; cell plate forms
Centrosome
microtubule organizing center (centriole)
G0 Stage
- Resting stage
- eg. animal neurons & female egg
Genes defined
Units of heredity passed thru genes from one gen. to the next
2 chromosomes in each pair;
Homologous chromosomes (same length & carry same traits)
Sex Chromosomes
- # 23
- Female; XX
- Males; XY
22 ‘non-sex’ chromosomes
Autosomes
Fertilization
Union Of Gametes
Fertilized egg;
Zygote (1 set of chromosomes from each parent)
