var presentation = ["<word>cell growth and cell division<\/word>","<word>precisely timed<\/word>","<word>carefully regulated<\/word>","<word>interphase<\/word>","<word>mitotic phase.<\/word>","<word>G1 phase, or the first gap<\/word>","<word>active at the biochemical level<\/word>","<word>S phase (synthesis phase)<\/word>","<word>two identical copies<\/word>","<word>Centrioles help organize cell division<\/word>","<word>G2 phase or second gap<\/word>","<word>cytoskeleton is dismantled<\/word>","<phrase>The cell cycle is an ordered series of events involving <strong data-readahead=\"cell growth and cell division\" class=\"presentation_word\">cell growth and cell division<\/strong> that produces two new daughter cells. Cells on the path to cell division proceed through a series of <strong data-readahead=\"precisely timed\" class=\"presentation_word\">precisely timed<\/strong> and <strong data-readahead=\"carefully regulated\" class=\"presentation_word\">carefully regulated<\/strong> stages of growth, DNA replication, and division that produce two genetically identical cells. The cell cycle has two major phases: <strong data-readahead=\"interphase\" class=\"presentation_word\">interphase<\/strong> and the <strong data-readahead=\"mitotic phase.\" class=\"presentation_word\">mitotic phase.<\/strong> During <strong data-readahead=\"interphase\">interphase<\/strong>, the cell grows and DNA is replicated. During the mitotic phase, the replicated DNA and cytoplasmic contents are separated and the cell divides.\n<strong data-readahead=\"interphase\">interphase<\/strong>\nDuring <strong data-readahead=\"interphase\">interphase<\/strong>, the cell undergoes normal processes while also preparing for cell division. For a cell to move from <strong data-readahead=\"interphase\">interphase<\/strong> to the mitotic phase, many internal and external conditions must be met. The three stages of <strong data-readahead=\"interphase\">interphase<\/strong> are called G1, S, and G2.\nG1 Phase\nThe first stage of <strong data-readahead=\"interphase\">interphase<\/strong> is called the <strong data-readahead=\"G1 phase, or the first gap\" class=\"presentation_word\">G1 phase, or the first gap<\/strong> because little change is visible. However, the cell is quite <strong data-readahead=\"active at the biochemical level\" class=\"presentation_word\">active at the biochemical level<\/strong>. The cell is accumulating the building blocks of chromosomal DNA and the associated proteins. At the same time, it is accumulating enough energy reserves to complete the task of replicating each chromosome in the nucleus.\nS Phase\nThroughout <strong data-readahead=\"interphase\">interphase<\/strong>, nuclear DNA remains in a semi-condensed chromatin configuration. In the <strong data-readahead=\"S phase (synthesis phase)\" class=\"presentation_word\">S phase (synthesis phase)<\/strong>, DNA replication results in the formation of <strong data-readahead=\"two identical copies\" class=\"presentation_word\">two identical copies<\/strong> of each chromosome, called sister chromatids. The sister chromatids are firmly attached at the centromere region. At this stage, each chromosome is made of two sister chromatids and is a duplicated chromosome. The centrosome is duplicated during the S phase. The two centrosomes will give rise to the mitotic spindle. This apparatus (mitotic spindle) later orchestrates the movement of chromosomes during mitosis. The centrosome consists of a pair of rod-like centrioles at right angles to each other. <strong data-readahead=\"Centrioles help organize cell division\" class=\"presentation_word\">Centrioles help organize cell division<\/strong>. Centrioles are not present in the centrosomes of many eukaryotic species, such as plants and most fungi.\nG2 Phase\nIn the <strong data-readahead=\"G2 phase or second gap\" class=\"presentation_word\">G2 phase or second gap<\/strong>, the cell replenishes its energy stores and synthesizes the proteins necessary for chromosome manipulation. Some cell organelles are duplicated, and the <strong data-readahead=\"cytoskeleton is dismantled\" class=\"presentation_word\">cytoskeleton is dismantled<\/strong> to provide resources for the mitotic spindle. There may be additional cell growth during G2. The final preparations for the mitotic phase must be completed before the cell is able to enter the first stage of mitosis.<\/phrase>","<word>multistep process<\/word>","<word>nuclear division<\/word>","<word>cytokinesis,<\/word>","<word>physical separation of the cytoplasmic components into two daughter cells.<\/word>","<word>prophase<\/word>","<word>prometaphase<\/word>","<word>metaphase<\/word>","<word>anaphase<\/word>","<word>telophase<\/word>","<phrase>The Mitotic Phase\nThe contents of the nucleus and the cytoplasm are divided to make two daughter cells. The mitotic phase is a <strong data-readahead=\"multistep process\" class=\"presentation_word\">multistep process<\/strong> during which the duplicated chromosomes are aligned, separated, and moved to opposite poles of the cell, and then the cell is divided into two new identical daughter cells. The first portion of the mitotic phase, mitosis, is composed of five stages, which accomplish <strong data-readahead=\"nuclear division\" class=\"presentation_word\">nuclear division<\/strong>. The second portion of the mitotic phase, called <strong data-readahead=\"cytokinesis,\" class=\"presentation_word\">cytokinesis,<\/strong> is the <strong data-readahead=\"physical separation of the cytoplasmic components into two daughter cells.\" class=\"presentation_word\">physical separation of the cytoplasmic components into two daughter cells.<\/strong>\nMitosis is divided into a series of phases-<strong data-readahead=\"prophase\" class=\"presentation_word\">prophase<\/strong>, <strong data-readahead=\"prometaphase\" class=\"presentation_word\">prometaphase<\/strong>, <strong data-readahead=\"metaphase\" class=\"presentation_word\">metaphase<\/strong>, <strong data-readahead=\"anaphase\" class=\"presentation_word\">anaphase<\/strong>, and <strong data-readahead=\"telophase\" class=\"presentation_word\">telophase<\/strong>-that result in the division of the cell nucleus.<\/phrase>","<word>Golgi apparatus<\/word>","<word>endoplasmic reticulum<\/word>","<word>nucleolus disappears<\/word>","<phrase>Prophase: is the first phase. Several events must occur to provide access to the chromosomes in the nucleus. The nuclear envelope starts to break into small vesicles. The <strong data-readahead=\"Golgi apparatus\" class=\"presentation_word\">Golgi apparatus<\/strong> and <strong data-readahead=\"endoplasmic reticulum\" class=\"presentation_word\">endoplasmic reticulum<\/strong> fragment and disperse to the periphery of the cell. The <strong data-readahead=\"nucleolus disappears\" class=\"presentation_word\">nucleolus disappears<\/strong>. The centrosomes begin to move to opposite poles of the cell. The microtubules extend between the centrosomes, pushing them farther apart as the microtubule fibers lengthen. The sister chromatids begin to coil more tightly and become visible under a light microscope.<\/phrase>","<word>processes continue to advance<\/word>","<word>kinetochore<\/word>","<phrase>Prometaphase: <strong data-readahead=\"processes continue to advance\" class=\"presentation_word\">processes continue to advance<\/strong> and culminate in the formation of a connection between the chromosomes and cytoskeleton. The remnants of the nuclear envelope disappear. The mitotic spindle continues to develop as more microtubules assemble and stretch across the length of the former nuclear area. Chromosomes become more condensed and visually discrete. Each sister chromatid attaches to spindle microtubules at the centromere via a protein complex called the <strong data-readahead=\"kinetochore\" class=\"presentation_word\">kinetochore<\/strong>.<\/phrase>","<word>metaphase plate,<\/word>","<word>equatorial plane,<\/word>","<phrase>Metaphase: all of the chromosomes are aligned in a plane called the <strong data-readahead=\"metaphase plate,\" class=\"presentation_word\">metaphase plate,<\/strong> or the <strong data-readahead=\"equatorial plane,\" class=\"presentation_word\">equatorial plane,<\/strong> midway between the two poles of the cell. The sister chromatids are still tightly attached to each other. At this time, the chromosomes are maximally condensed.<\/phrase>","<word>now called a chromosome<\/word>","<word>non-kinetochore<\/word>","<word>metaphase<\/word>","<phrase>Anaphase: the sister chromatids at the equatorial plane are split apart at the centromere. Each chromatid, <strong data-readahead=\"now called a chromosome\" class=\"presentation_word\">now called a chromosome<\/strong>, is pulled rapidly toward the centrosome to which its microtubule was attached. The cell becomes visibly elongated as the <strong data-readahead=\"non-kinetochore\" class=\"presentation_word\">non-kinetochore<\/strong> microtubules slide against each other at the <strong data-readahead=\"metaphase\" class=\"presentation_word\">metaphase<\/strong> plate where they overlap.<\/phrase>","<word>monomers<\/word>","<phrase>Telophase: all of the events that set up the duplicated chromosomes for mitosis during the first three phases are reversed. The chromosomes reach the opposite poles and begin to de-condense (unravel). The mitotic spindles are broken down into <strong data-readahead=\"monomers\" class=\"presentation_word\">monomers<\/strong> that will be used to assemble cytoskeleton components for each daughter cell. Nuclear envelopes form around chromosomes.<\/phrase>","<word>physical separation of the cytoplasmic components into two daughter cells.<\/word>","<phrase>Cytokinesis is the second part of the mitotic phase during which cell division is completed by the <strong data-readahead=\"physical separation of the cytoplasmic components into two daughter cells.\" class=\"presentation_word\">physical separation of the cytoplasmic components into two daughter cells.<\/strong> Although the stages of mitosis are similar for most eukaryotes, the process of cytokinesis is quite different for eukaryotes that have cell walls, such as plant cells.<\/phrase>"];
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