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Cell Reproduction. Structure of DNA during cell division Chromatid Centromere Chromatin. Chromosomes. Sex chromosomes Autosomes Homologous pairs Karyotype Diploid vs. Haploid. Chromosomes. Binary fission Results in two identical offspring/new cells. Prokaryotic Cell Division.
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Structure of DNA during cell division • Chromatid • Centromere • Chromatin Chromosomes
Sex chromosomes • Autosomes • Homologous pairs • Karyotype • Diploid vs. Haploid Chromosomes
Binary fission • Results in two identical offspring/new cells Prokaryotic Cell Division
Mitosis • Occurs in somatic cells • New cells are identical Eukaryotic Cell Division
True • False All of the non sex chromosomes are called autosomes.
Interphase and Mitosis Cell Cycle
Not considered Mitosis • G1 – growth phase • S – DNA is copied • G2 – growth phase; microtubules formed Interphase
Prophase • Metaphase • Anaphase • Telophase • Cytokinesis Mitosis
Centrosomes (centrioles) appear and move towards ends of cell • DNA as chromosomes is visible • Spindle fibers forms • Nuclear envelope begins to break down Prophase
Chromosomes line up in the middle of the cell • Spindle fibers attach to chromosomes Metaphase
True • False If a fruit fly has 8 chromosomes, then it’s haploid number is 4.
Spindle fibers pull apart the chromatids • New single chromosomes pulled towards pole Anaphase
Spindle fibers break down • Chromosomes return to chromatin form • Nuclear envelope reforms Telophase
Cleavage furrow forms • Parent cell cleaved into two identical offspring/new cells Cytokinesis
Prophase • Metaphase • Anaphase • Telophase [Default] [MC Any] [MC All] In which phase of mitosis do chromatids separate and become individual chromosomes?
Asters • Cell plate forms during cytokinesis; eventually becomes cell wall Plant Cell Mitosis
G1 growth – cell must be healthy and large enough to divide; if not, then the cycle will not continue • G2 synthesis – DNA that was copied will be checked and repairs made • M – cell will exit mitosis Checkpoints
Formation of gametes/haploid cells • Involves two distinct stages • Also goes through G1, S, and G2 phases • Occurs in diploid sex cells Meiosis
Chromosomes and spindle fibers appear • Nuclear envelope begins to dissolve • Homologous chromosomes pair up • Crossing over can occur in a tetrad Prophase I
Tetrads randomly line up in the middle • Spindle fibers attach to each homologous pair Metaphase I
Spindle fibers pull apart the tetrads, resulting in chromatids being pulled to opposite ends of the cell • Independent assortment Anaphase I
Chromosomes reach the end of the cell • Cytokinesis begins • 2 Haploid cells Telophase I and Cytokinesis
Spindle fibers form • Nuclear envelope dissolves Prophase II
Chromosomes line up along the middle of the cell Metaphase II
Chromatids are pulled apart by the spindle fibers. Anaphase II
Nuclear membrane forms around each set of chromosomes • Cleavage furrow begins to form • 4 Haploid cells Telophase II and Cytokinesis
Sperm • Spermatogenesis • Egg • Oogenesis Gametes