TAMU Biology 111 final Exam Questions and Answers 100% Pass

TAMU Biology 111 final Exam Questions and Answers 100% Pass Reasons why cells divide - Answer- -growth -cell and tissue repair -maintenance -reproduction When does DNA replication occur - Answer- before cell division Prokaryotes accomplish cell division through - Answer- binary fission + cytokinesis Eukaryotes accomplish cell division through - Answer- mitosis + cytokinesis Binary fission - Answer- asexual reproduction by separation of cell into new cells Steps for binary fission - Answer- -CIRCULAR dna attaches to membrane -dna is replicated -plasma membrane elongates -cytokinesis occurs and membrane splits into two new cells Two major phases of cell cycle - Answer- -Interphase -Mitotic phase Interphase - Answer- -G1 phase, S phase, and G2 phase -longest part of cell cycle G1 phase of Interphase - Answer- Primary Growth Phase -Most of interphase is spent here -cell doubles in size -organelles duplicated -most proteins are produced here G0 phase of Interphase - Answer- A non-dividing state in which a cell has left the cell cycle. S phase of Interphase - Answer- DNA replication occurs -Identical copies of Sister chromatids are joined at centromere -Centromeres produce mitotic spindles to move the chromosomes. G2 phase - Answer- -Energy, proteins, and ribosomes are made (in preparation for new cell's needs) -Organelles reproduce -DNA is checked for damage and completeness Mitotic phase consists of 2 major steps - Answer- -Karyokinesis: Division of the nucleus -Cytokinesis: Division of cytoplasm Mitosis: Prophase - Answer- -nuclear envelope breaks down -organelles move towards edge of cell -nuclear envelope disappears -centrosomes migrate to poles -microtubules of spindles form -sister chromatids coil tighter -chromosomes are still TWO sister chromatids Mitotic spindle - Answer- apparatus of microtubules that arrises from centromere that attaches to spindle fibers Mitosis: Metaphase - Answer- Separation stage -Chromosomes line up along metaphase plate -Sister chromatids remain attached at centromere by cohesion proteins -chromosomes are still TWO sister chromatids Mitosis: Prometaphase - Answer- -Sister chromatids develop protein called KINETOCHORE, which attaches chromatids to spindle microtubules -chromosomes are still TWO sister chromatids Mitosis: Anaphase - Answer- Chromatid speration -Cohesion protein disintegrates -Separated sister chromatids move in opposite directions towards centrosomes -cell elongates to have enough space for the poles -chromosomes are now each ONE sister chromatid Mitosis: Telophase - Answer- End stage -Chromosomes reach opposite poles and begin to decondense -Nuclear envelopes form around each set of chromosome