Cell Cycle and Cell Division Latest 2024 Graded A

Cell Cycle and Cell Division Latest 2024 Graded A Cell Cycle An ordered sequence of events in the life of a cell Mitosis A process of nuclear division in eukaryotic cells conventionally divided into five stages: prophase, prometaphase, metaphase, anaphase, and telophase. Mitosis conserves chromosome number by allocating replicated chromosomes equally to each of the daughter nuclei. Cytokinesis The division of the cytoplasm to form two separate daughter cells immediately after mitosis, meiosis I, or meiosis II. Cell Division The reproduction of cells Chromosomes A cellular structure carrying genetic material, found in the nucleus of eukaryotic cells. Each chromosome consists of one very long DNA molecule and associated proteins Chromatin The complex of DNA and proteins that makes up eukaryotic chromosomes. When the cell is not dividing, chromatin exists in its dispersed form, as a mass of very long, thin fibers that are not visible with a light microscope Somatic Cells Any cell in a multicellular organism except a sperm or egg or their precursors. Gametes A haploid reproductive cell, such as an egg or sperm. Gametes unite during sexual reproduction to produce a diploid zygote. Sister Chromatids Two copies of a duplicated chromosome attached to each other by proteis at the centromere and sometimes, along the arms. While joined, two sister chromatids make up one chromosome. Chromatids are eventually separated during mitosis or meiosis II Centromere In a duplicated chromosome, the region on each sister chromatid where they are most closely attached to each other by proteins that bind to specific DNA sequences; this close attachment causes a constriction in the condensed chromosome. (An uncondensed, unduplicated chromosome has a single centromere, identified by its DNA sequence.) How many chromatids are in a duplicated chromosome? 2 mitotic (M) phase The phase of the cell cycle that includes mitosis and cytokinesis. interphase The period in the cell cycle when the cell is not dividing. During interphase, cellular metabolic activity is high, chromosomes and organelles are duplicated, and cell size may increase. Interphase often accounts for about 90% of the cell cycle. aster A radial array of short microtubules that extends from each centrosome toward the plasma membrane in an animal cell undergoing mitosis. binary fission A method of asexual reproduction by "division in half." In prokaryotes, binary fission does not involve mitosis, but in single-celled eukaryotes that undergo binary fission, mitosis is part of the process. somatic cell Any cell in a multicellular organism except a sperm or egg or their precursors. transformation (1) The conversion of a normal animal cell to a cancerous cell. (2) A change in genotype and phenotype due to the assimilation of external DNA by a cell. When the external DNA is from a member of a different species, transformation results in horizontal gene transfer. asexual reproduction A type of reproduction involving only one parent that produces genetically identical offspring by budding or by the division of a single cell or the entire organism into two or more parts. sexual reproduction A type of reproduction in which two parents give rise to offspring that have unique combinations of genes inherited from the gametes of the two parents. diploid cell A cell containing two sets of chromosomes (2n), one set inherited from each parent. haploid cell A cell containing only one set of chromosomes (n). Meiosis Meiosis is essential to sex, because it enables each parent to contribute one set of chromosomes-- half the total-- to each diploid offspring. G1 Phase The first gap, or growth phase, of the cell cycle, consisting of the portion of interphase before DNA synthesis begins. S Phase The synthesis phase of the cell cycle; the portion of interphase during which DNA is replicated. G2 Phase The second gap, or growth phase, of the cell cycle, consisting of the portion of interphase after DNA synthesis occurs. Centriole A structure present in the cytoplasm of animal cells that functions as a microtubule-organizing center and is important during cell division. A centrosome has two centrioles. Metaphase Plate An imaginary structure located at a plane midway between the two poles of a cell in metaphase on which the centromeres of all the duplicated chromosomes are located. Cleavage Furrow The first sign of cleavage in an animal cell; a shallow groove around the cell in the cell surface near the old metaphase plate. Cell Plate A membrane-bounded, flattened sac located at the midline of a dividing plant cell, inside which the new cell wall forms during cytokinesis. Binary Fission A method of asexual reproduction by "division in half." In prokaryotes, binary fission does not involve mitosis, but in single-celled eukaryotes that undergo binary fission, mitosis is part of the process. Cell cycle control system A cyclically operating set of molecules in the eukaryotic cell that both triggers and coordinates key events in the cell cycle. Cell Cycle An ordered sequence of events in the life of a cell Mitosis A process of nuclear division in eukaryotic cells conventionally divided into 4 stages: prophase, metaphase, anaphase, and telophase. Mitosis conserves chromosome number by allocating replicated chromosomes equally to each of the daughter nuclei. What are the 4 phases of mitosis? Prophase Metaphase Anaphase Telophase Prophase The first stage of mitosis, in which 3 things happen: 1) chromatin condenses into chromosomes 2) Nuclear envelope breaks down 3) mitotic spindle fibers are assembled. Metaphase The 2nd stage of mitosis, in which the spindle is complete and the chromosomes, attached to microtubules at their kinetochores, are all aligned at the metaphase plate. Anaphase The 3rd stage of mitosis, in which the chromatids of each chromosome have separated and the daughter chromosomes are moving to the poles of the cell. Telophase The 4th and final stage of mitosis, in which daughter nuclei are forming and cytokinesis has typically begun. Cytokinesis The division of the cytoplasm to form two separate daughter cells immediately after mitosis, meiosis I, or meiosis II. Chromosomes A cellular structure carrying genetic material, found in the nucleus of eukaryotic cells. Each chromosome consists of one very long DNA molecule and associated proteins Chromatin The complex of DNA and proteins that makes up eukaryotic chromosomes. When the cell is not dividing, chromatin exists in long, thin fibers that are not visible with a light microscope Centromere In a duplicated chromosome, the region on each sister chromatid where they are most closely attached to each other by proteins that bind to specific DNA sequences; this close attachment causes a constriction in the condensed chromosome. (An uncondensed, unduplicated chromosome has a single centromere, identified by its DNA sequence.) How many chromatids are in ONE duplicated chromosome? 2 interphase The period in the cell cycle when the cell is not dividing. Interphase often accounts for about 90% of the cell cycle. spindle fibers Microtubules involved in the movement of chromosomes during mitosis. Through a microscope, you can see a cell with two nuclei.. This cell is most likely in what state Interphase, Prophase, Metaphase, Anaphase, Telophase a plant cell in the process of cytokinesis. Which of the following does NOT occur during mitosis? condensation of the chromosomes spindle formation separation of the spindle poles separation of sister chromatids replication of the DNA replication of the DNA happens during interphase (not parto What is Mitosis? Cell division that generates new cells for growth and repair. The division of one cell into two genetically identical daughter cells What are the 7 Phases of the Cell Cycle? Interphase -S- Phase -G2 Phase Mitotic Phase -Mitosis -Cytokinesis G1 What are 2 parts of cell division? Mitosis and Cytokinesis Cell division consists of two processes: mitosis and cytokinesis. Mitosis— division of the nucleus and its chromosomes What happens during prophase? 1. The nucleoli disappear 2. Chromatin fibers coil up to become discrete chromosomes. 3. Each chromosome consists of two identical sister chromatids, joined at the centromere. 4. Microtubules grow out from the centrosomes, initiating formation of the mitotic spindle. What happens during metaphase? 1. The mitotic spindle is fully formed 2. The microtubules attached to kinetochores move the chromosomes to the metaphase plate, an imaginary plane equidistant from the poles. What happens during anaphase? 1. The two centromeres of each chromosome come apart, separating the sister chromatids. 2. The spindle fibers pull apart the chromatids to form two nucleus of the cells. What happens during Telophase? 1. nuclear envelopes form around the identical sets of chromosomes at the two poles of the cell. 2. The chromosomes uncoil 3. Nucleoli appear in the two new nuclei. G1 Phase The first gap, or growth phase, of the cell cycle, consisting of the portion of interphase before DNA synthesis begins. S Phase The synthesis phase of the cell cycle; the portion of interphase during which DNA is replicated. G2 Phase The second gap, or growth phase, of the cell cycle, consisting of the portion of interphase after DNA synthesis occurs. Centrosome A structure present in the cytoplasm of animal cells that functions as a microtubule-organizing center and is important during cell division. A centrosome has two centrioles. The function of the mitotic cell cycle is to produce daughter cells that _____. are genetically identical to the parent cell (assuming no mutation has occurred) The region of a chromosome holding the two double strands of replicated DNA together is called _____. a centromere "Cytokinesis" refers to _____. division of the cytoplasm -The final stage of the cell cycle -is the division of the cytoplasm that follows the mitotic division of the nucleus. -END RESULT: Two genetically identical cells. In telophase of mitosis, the mitotic spindle breaks down and the chromatin uncoils. This is essentially the opposite of what happens in _____. Prophase During prophase, we observe the formation of the spindle, the condensation of chromatin, and the disappearance of the nucleolus. The complex of DNA and protein that makes up a eukaryotic chromosome is properly called _____. chromatin A cell entering the cell cycle with 32 chromosomes will produce two daughter cells, each with _____. 64 chromosomes 32 pairs of chromosomes 64 pairs of chromosomes none of the above None of the listed responses is correct. None of the above Chromatids are _____. A. found only in aberrant chromosomes B.composed of RNA C. identical copies of each other if they are part of the same chromosome D. held together by the centrioles E. the bacterial equivalent of eukaryotic chromosomes identical copies of each other if they are part of the same chromosome If a cell contains 60 chromatids at the start of mitosis, how many chromosomes will be found in each daughter cell at the completion of the cell cycle? 120 45 60 30 15 30 During interphase, the genetic material of a typical eukaryotic cell is _____. dispersed in the nucleus as long strands of chromatin DNA replication occurs in _____. the S phase of interphase in both somatic and reproductive cells