Term
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Definition
| the ability of organisms to reproduce, the continuity of life depends on this reproduction of cells. This cell division occurs as part of the cell cycle. |
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Term
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Definition
| occurs during cell division, which a parent cell divides into two. |
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Term
| cell division in a unicellular organism... |
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Definition
| results in the reproduction of an entire organism, increasing the population. |
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Term
| cell division on a larger scale... |
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Definition
| can produce progeny for some multicellular organisms. This includes organisms that can grow by fission. |
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Term
| cell division is central to.... |
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Definition
| the development of a multicellular organism that begins as a fertilized egg or zygote. |
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Term
| multicellular organisms also use cell division to... |
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Definition
| repair and renew cells that die from normal wear and tear or accidents |
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Term
| cell division requires the distribution of...... |
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Definition
| identical genetic material-DNA- into two daughter cells. The fidelity with which DNA is passed along, without dilution, from one generation to the next is truly remarkable. |
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Term
| A dividing cell duplicates its DNA... |
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Definition
| allocates the two copies to opposite ends of the cell, and then divides into two daughter cells. |
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Term
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Definition
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Term
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Definition
| the genome is often a single long DNA molecule |
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Term
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Definition
| the genome consists of several DNA molecules |
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Term
| a human cell must duplicate 3 m of DNA and..... |
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Definition
| separate the two copies such that each daughter cell ends up with a complete genome |
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Term
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Definition
| packaging of DNA molecules. Every eukaryotic species has a characteristic number of chromosomes in the nucleus. |
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Term
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Definition
| human somatic cells (body cells) have 46 chromosomes |
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Term
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Definition
| human gametes or germ cells (sperm or eggs) have 23 chromosomes, half the number in a somatic cell. |
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Term
| each eukaryotic chromosomes |
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Definition
| consists of a long, linear DNA molecule |
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Term
| each chromosome has hundreds to thousands of genes..... |
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Definition
| the units that specify an organism's inherited traits |
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Term
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Definition
| are proteins that maintain its strucre and help control gene activity |
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Term
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Definition
| a DNA-protein complex which is organized into a long thin fiber |
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Term
| after the DNA duplication |
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Definition
| chromatin condenses, coiling and folding to make a smaller package |
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Term
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Definition
| each duplicated chromosome consists of two sister chromatids which contain identical copies of the chromosome's DNA |
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Term
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Definition
| the narrow area where as the sister chromatids condense, the region where the strands connects shrinks to this area |
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Term
| after the sister chromatids condense, later, the sc's are pulled.... |
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Definition
| apart and repackaged into two new nuclei at opposite ends of the parent cell |
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Term
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Definition
| the process of the formation of the two daughter nuclei |
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Term
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Definition
| usually follows mitosis, which is the division of the cytoplasm |
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Term
| mitosis and cytokinesis take one cell and... |
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Definition
| produce two cells that are the genetic equivalent of the parent |
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Term
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Definition
| 23 chromosomes from each parent: one set in an egg and one set in sperm |
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Term
| the fertilized egg or zygote... |
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Definition
| underwent trillions of cycles of mitosis and cytokinesis to produce a fully developed multicellular human |
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Term
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Definition
| (sperm or eggs) are produced only in the gonads (testes and ovaries) |
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Term
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Definition
| a variation of cell division in the gonads, which yields four daughter cells, each with half of the chromosomes of the parent |
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Term
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Definition
| reduces the number of chromosomes from 46 to 23 |
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Term
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Definition
| two gametes together and doubles the number of chromosomes to 46 again |
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Term
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Definition
| of the cell cycle alternates with the much longer interphase. the M phase includes mitosis and cytokinesis. Interphase accounts for 90% of the cell cycle. |
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Term
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Definition
| the cell grows by producing proteins and cytoplasmic organelles, copies its chromosomes, and prepares for cell division. |
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Term
| interphase is divided into 3 substages |
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Definition
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Term
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Definition
| ("first gap") centered on growth |
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Term
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Definition
| ("synthesis") when DNA synthesis takes place and the chromosomes are duplicated |
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Term
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Definition
| ("second gap") where the cell completes preparations for cell division, and divides the "M" phase |
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Term
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Definition
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Term
| mitosis is divided into five subphases: |
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Definition
| prophase, prometaphase, metaphase, anaphase, and telophase |
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Term
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Definition
| the chromosomes have been duplicated but are loosely packed |
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Term
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Definition
| have been duplicated and begin to organize microtubules into an aster ("star"), during late interphase |
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Term
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Definition
| the chromosomes are tightly coiled, with sister chromatids joined together, the nucleoli disappear, and the mitotic spindle begins to from and appears to push the centrosomes away from each other toward opposite ends (poles) of the cells |
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Term
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Definition
| the nuclear envelope fragments and microtubules from the spindle interact with the chromosomes |
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Term
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Definition
| during prometaphase, microtubules from one pole attach to on of two kinetochores, special regions of the centromere where microtubules from the other pole attach to the other kinetochore |
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Term
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Definition
| special regions of the centromere where microtubules from the other pole attach to the other kinetochore, this is during pro metaphase and microtubules from one pole attach to one or two of these |
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Term
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Definition
| the spindle fibers push the sister chromatids until they are all arranged at the metaphase plate |
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Term
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Definition
| an imaginary plane equidistant between the poles, defining metaphase |
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Term
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Definition
| the centromeres divide, separating the sister chromatids, each is now pulled toward the pole to which it is attached by spindle fibers. by the end, the two poles have equivalent collections of chromosomes. |
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Term
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Definition
| the cell continues to elongate as free spindle fibers from each centrosome push off each other. Two nuclei begin for form, surrounded by the fragments of the parent's nuclear envelope. Chromatin becomes less tightly coiled. Cytokinesis (division of the cytoplasm) begins |
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Term
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Definition
| fibers composed of microtubules and associated proteins, is a major driving force in mitosis. |
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Term
| as the spindle assembles during prophase... |
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Definition
| the elements come from partial disassembly of the cytoskeleton. Th spindle fibers elongate by incorporating more subunits of the protein tubulin. |
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Term
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Definition
| asssembly of the spindle microtubules starts in the centrosome. The centrosome, is a microtubule-organizing center, of animals has a pair of centrioles at the center, but the function of the centrioles is somewhat undefined. |
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Term
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Definition
| the two centrosomes are located near the nucleus. as the spindle fibers grow from them , the centrioles are pushed apart. By the end of prometaphase they develop as the spindle poles at opposite ends of the cell. |
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Term
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Definition
| located in each sister chromatid, which holds proteins and chromosomal DNA at the centromere. The kinetochores of the joined sister chromatids face in opposite directions. |
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Term
| during prometaphase, some spindle microtubeles..... |
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Definition
| attach to the kinetochores |
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Term
| when a chromosme's kinetochore is "captured" by microtubules... |
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Definition
| the chromosome moves toward the pole from which those microtubules come from. When these microtubules attach to the other pole, this movement stops and a tug-of-war ensues. |
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Term
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Definition
| the chromosome settles midway between the two poles of the cell. Other microtubules from opposite poles interact as well, elongating the cell |
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Term
| nonkinetichore microtubules... |
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Definition
| are responsible for lengthening the cell along the axis defined by the poles. These microtubules interdigitate across the metaphase plate. During anaphase motor proteins push microtubules from opposite sides away from each other. At the same time, the addition of new tubulin monomers extends their length. |
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Term
| first sight of cytokinesis |
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Definition
| (cleavage) is the appearance of a cleavage furrow in the cell surface near the old metaphase plate. |
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Term
| on the cyoplasmic side of the cleavage furrow... |
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Definition
| a contractile ring of actin microfilaments and the motor protein myosin form. Contraction of the ring pinches the cell in two. |
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Term
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Definition
| plants have cell walls, and involves a completely different mechanism. During the telophase, vesicles from the Golgi coalesce at the metaphase plate, forming the cell plate. |
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Term
| the cell plate enlarges.... |
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Definition
| until its membranes fuse with the plasma membrane at the perimeter with the contents of the vesicles forming new wall material in between. |
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Term
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Definition
| prokaryotes(bacteria) reproduce by binary fission, not mitosis. Most bacterial genes are located on a single bacterial chromosome which consists of a circular DNA molecule and associated proteins. |
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Term
| while bacteria do not have as many genes or DNA molecules as those in eukaryotes... |
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Definition
| their circular chromosome is still highly folded and coiled in the cell. |
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Term
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Definition
| in binary fission, chromosome replication begins at one point in the circular chromosome or the ORI site. These copied regions begin to move to opposite ends of the cell |
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Term
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Definition
| inward growth of the plasma membrane, dividing the parent cell into two daughter cells, each with a complete genome. |
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Term
| two types of unicellular algae |
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Definition
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Term
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Definition
| replicated chromosomes are attached to the nuclear envelope |
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Term
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Definition
| the spindle develops within the nucleus |
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Term
| the timing and rates of cell division in different parts of animal... |
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Definition
| are crucial for normal growth, development, and maintenance. The frequency of cell division varies with different cell types |
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Term
| some human cells divide frequently throughout life(skin cells)... |
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Definition
| others have the ability to divide, but keep it in reserve (liver cells), and mature nerve and muscle cells do not appear to divide at all after maturity. |
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Term
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Definition
| to be driven by specific chemical signals in the cytoplasm. Fusion of an S phase and a G1 phase cell, induces the G1 nucleeaus to start Sphase. Fusion of a cell in mitosis with one in interphase induces the second cell to enter mitosis. |
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Term
| cell cycle control system |
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Definition
| the distinct events of the cell cycle are directed by a distinct, CCCS. The control cycle has a built-in clock, but it is also regulated by internal controls and external cues. |
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Term
| checkpoint in the cell cycle |
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Definition
| is a critical control point where stop and go signals regulate the cycle. |
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Term
| man signals registered at checkpoints... |
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Definition
| come from cellular surveillance mechanisms |
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Term
| 3 major checkpoints are found in a cell cycle. They are found in these phases: |
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Definition
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Term
| for many cells the G1 checkpoint.. |
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Definition
| AKA the restriction point in mammalian cells, is the most important |
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Term
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Definition
| when a cell does not receive a go-ahead signal, the cell will exit the cycle and switch to a nondividing state. |
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Term
| most human cells are in which pase |
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Definition
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Term
| liver cells being "called back" |
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Definition
| liver cells can be "called back" to the cell cycle by external cues (growth factors), but highly specialized nerve and muscle cells never divide. |
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Term
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Definition
| in the abundance and activity of control molecules pace the cell cycle. Some of these molecules are protein kinases that activate or deactivate other proteins by phosphorylating them. |
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Term
| levels of kinases in rhythmic fluctuations.... |
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Definition
| are present in constant amounts, but these kinases require a second protein, a cyclin, to become activated |
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Term
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Definition
| (Cdks) forms from the complex of kinases and cyclin |
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Term
| cyclin levels rise sharply throughout.... |
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Definition
| interphase, then fall abruptly during mitosis. |
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Term
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Definition
| (maturation or M phase promoting factor) a peak in the activity of one cyclin-Cdk complex which correspons to peaks in cyclin concentration |
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Term
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Definition
| the cell's passage past the G2 checkpoint into the M phase. MPF promotes mitosis by phosphorylating a variety of other protein kinases. MPF also stimulates fragmentation of the nuclear envelope and the breakdown of cyclin, dorpping cyclin and MPF levels during mitosis and inactivating MPF. |
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Term
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Definition
| is regulated by at least three Cdk proteins and seeveral cyclins |
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Term
| The M phase checkpoint... |
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Definition
| ensures that all the chromosomes are properly attached to the spindle at the metaphase plate before anaphase. |
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Term
| M phase also ensures that daughter cells.. |
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Definition
| do not end up with missing or extra chromosomes. The signal to delay anaphase originates at kinetochores that have not yet attached to spindle microtubules, which keeps the anaphase-promoting complex (APC) in an inactive state. |
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Term
| a variety of______ can influence cell division |
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Definition
| external chemical and physical factors |
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Term
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Definition
| proteins released by one group of cells that stimulate other cells to divide |
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Term
| example of a growth factor |
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Definition
| platelet-derived growth factors (PDGF), produced by platelet blood cells, bind to tyrosine-kinase receptors of fibroblasts, a type of connective tissue cell |
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Term
| each cell type probably responds... |
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Definition
| specifically to a certain growth factor or combination of factors. |
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Term
| role of PDGF a observed in cell culture.... |
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Definition
| fibroblasts in culture will only divide in the presence of medium that also contains PDGF. In a living organism, platelets release PDGF in the vicinity of an injury. The proliferation of fibroblasts help heal the wound. |
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Term
| growth factors appear to be a key in______ of cell division |
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Definition
| density-dependent inhibition |
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Term
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Definition
| cultured cells normally divide until they form a single layer on the inner surface of the culture container |
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Term
| most animal cells also exhibit _____ for cell division |
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Definition
| anchorage dependence. To divide they must be anchored to a substratum typically the extracellular matrix of a tissue. |
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Term
| cancer cells are free of both... |
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Definition
| density-dependent inhibition and anchorage dependence |
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Term
| cancer cells divide excessively and invade... |
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Definition
| other tissues because they are free of the body's control mechanisms. |
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Term
| cancer cells do not stop dividing when.... |
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Definition
| growth factors are depleted either because they manufacture their own, have an abnormality in the signaling pathway, or have a problem in the cell cycle control system. |
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Term
cancer cells may divide....
In contrast... |
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Definition
indefinitely if they have a continual supply of nutrients.
nearly all mammalian cells divide 20 to 50 times under culture conditions before they stop, age, and die. |
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Term
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Definition
| immortal. HeLa cells from a tumore removed from a woman(Henrietta Lacks) in 1951 are still reproducing in culture. |
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Term
| the abnormal behavior of cancer cells begins.... |
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Definition
| when a single cell in a tissue undergoes a transformation that converts it from a normal cell to a cancer cell. Normally, the immune system recognize and destroys transformed cells. |
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Term
| cells that evade immune system destruction... |
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Definition
| proliferate to form a tumor, a mass of abnormal cells |
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Term
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Definition
| if the abnormal cells remain at the originating site. Most do not cause serious problems and can be removed by surgery. |
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Term
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Definition
| the cells leave the original site to impair the functions of one or more organs. This typically fits the colloquial definition of cancer. |
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Term
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Definition
| cancer cells often lose attachment to nearby cells, are carried by the blood and lymph system to other tissues, and start more tumors in this event. |
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Term
| treatments for metastasizing cancers include... |
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Definition
| high-energy radiation and chemotherapy with toxic drugs. These treatments target actively dividing cells. |
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Term
| cellular transformation always involves.... |
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Definition
| the alteration of genes that influence the cell cycle control system. |
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Term
| offspring acquire genes from parents by... |
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Definition
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Term
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Definition
how offspring differ somewhat from parents and siblings |
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Term
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Definition
| the transmission of traits from one generation to the next. Also called inheritance |
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Term
| parents endow their offspring with... |
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Definition
| coded information in the form of genomes and genes |
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Term
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Definition
| specific traits that emerge as we develop from ferilized eggs into adults. |
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Term
| genes are specific segments of.. |
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Definition
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Term
| genetic info is transmittes as... |
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Definition
| specific sequences of the four deoxyribonucleotidees (A,C,G,&T) in DNA |
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Term
| most genes program cells to... |
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Definition
| synthesize specific enzymes and other proteins that produce an organism's inherited traits. |
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Term
the transmission of hereditary traits... |
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Definition
| has its molecular basis in the precise replication of DNA. This produces copies of genes that can be passed from parents to offspring. |
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Term
| in plants and animals, sperm and ova(unvertilized eggs) transmit... |
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Definition
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Term
| after fertilization(fusion) of a sperm cell with an ovum... |
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Definition
| genes from both parents are present in the nucleus of a fertilized egg. |
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Term
| DNA in the genome in eukaryotic cells is... |
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Definition
| subdivided into chromosomes in the nucleus. Tiny amounts of DNA are found in mitochondria and chloroplasts in the cytoplasm. |
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Term
| * Every living species has a... |
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Definition
| characteristic number of chromosomes. Humans have 46 in almost all of their cells. |
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Term
| each chromosome consists of a single.. |
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Definition
| DNA molecule in association with various proteins. |
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Term
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Definition
a specific location where each chromosome has hundres or thousands of genes |
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Term
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Definition
| a single individual passes along copies of all its genes to its offspring. |
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Term
| single-celled eukaryotes reproduces asexually by... |
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Definition
| mitotic cell division to produce two identical daugter cells |
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Term
even some multiceelular eukaryotes, liky hydra, can reproduce by... |
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Definition
| budding cells produced by mitosis. Each cell is a clone |
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Term
| sexual reproduction results in great... |
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Definition
variation among offspring |
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Term
| in humans, each ____(all cells other than sperm or ovum) has 46 chromosomes. |
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Definition
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Term
| each chromosome can be distinguihed by... |
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Definition
| its size, position of the centromere, and by pattern of staining with certain dyes. |
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Term
a karyotype display of 46 chromosomes shows... |
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Definition
23 pairs of chromosomes, each pair with the same lenght, centromere position , and staining pattern. |
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Term
| homologous chromosome pairs carry.. |
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Definition
| genes that control the same inherited characters. |
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Term
| karyotyps are often prepared with |
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Definition
|
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Term
| an exception to the rule of homolgous chromosomes is found in.... |
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Definition
| sex chromosomes, the X and the Y |
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Term
| human females have a homologous pair of |
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Definition
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Term
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Definition
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Term
the other 22 pairs are called |
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Definition
|
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Term
| the occurence of homologous pairs of chromosomes is... |
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Definition
| a consequence of sexual reproduction. |
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Term
| we inherit one chromosome of each... |
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Definition
| homologous pair from each parent. The 46 chromosomses in a somatic cell can be viewed as two sets of 23, a meternal set and a paternal set. |
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Term
| sperm cells or ova(gametes) have only... |
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Definition
| one set of chromosomes - 22 autosomes and an X or a Y |
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Term
| a cell with a single chromosomes set is _____ |
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Definition
| haploid. For humans, the haploid number of chromosomes is 23 (n=23) |
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Term
| by means of sexual intercourse a haploid sperm.. |
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Definition
| reaches and fuses with a haploid ovum. |
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Term
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Definition
| when a haploid sperm and a haploid ovum fuse, resulting in fertilization. |
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Term
| the fertilized egg ____, now has... |
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Definition
| zygote; two haploid sets of chromosomes bearing genes from the maternal and paternal family lines. |
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Term
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Definition
they zygote and all cells with two sets of chromosomes. For humans, the diploid number of chromosomes is 46 (2n = 46) |
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Term
as an organism develops from a zygote to a sexuall mature dult, the zygote's genes are... |
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Definition
| passed on to all somatic cells by mitosis. |
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Term
| gametes, which develop in te gonads, are... |
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Definition
|
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Term
| gametes undergo the process of... |
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Definition
| meiosis in which the chromosome number is halved. Human spern or ova have a haploid set of 23 different chromosomes, one from each homologous pair. |
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Term
| fertilization resotres the diploid condition by... |
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Definition
| combining two haploid sets of chromosomes. |
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Term
| fertilization and meiosis alternate in... |
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Definition
|
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Term
| they life cycle of humans and other animals is typical of... |
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Definition
| one major type. Gametes, produced by meiosis, are the only haploid cells. |
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Term
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Definition
| divisions themselves, but fuse to form a diploid zygote that divides by mitosis to produce a multicellular organism. |
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Term
| most fungi and some protists have a second... |
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Definition
| type of life cycle. The zygote is the only diploid phase. |
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Term
| after fusion of two gametes to form a zygote, the zygote.... |
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Definition
| undergoes meiosis to produce haploid cells. These haploid cells undergo mitosis to develp into a haploid multicellulare adult organism. |
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Term
| some haploid cells develop into ____ by mitosis. |
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Definition
|
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Term
| alternation of generation |
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Definition
| a third type of life that plants and some algea go through |
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Term
| tthe alternation of generation life cycle includes both... |
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Definition
| haploid (gametophyte) and diploid (sporophyte) multicellulare stages. |
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Term
| meiosis by the sporophyte produces... |
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Definition
| haploid spores that develop by mitosis into the gametophyte. |
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Term
| gametes produced via mitosis by the gametophyte fuse to.. |
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Definition
| from the zygote which produces the sporophyte by mitosis. |
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Term
| many steps of meiosis resemble stpes in... |
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Definition
| mitosis. Both are precede by the replication of chromosomes. |
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Term
| in meiosis there are two consecutive cell divisions.... |
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Definition
| meiosis I and meiosis II, which result in four daughter cells. |
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Term
| each final daughter cell has only... |
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Definition
| half as many chromosomes as the parent cell. |
|
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Term
| in cell division the mitotic (M) phase of the cell cycle alternates... |
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Definition
| with the much longer interphase. The M phase includes mitosis and cytokinesis. Interphase accounts for 90% of the cell cycle. |
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Term
|
Definition
| where the assembly of the spindle microtubules starts |
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Term
| the centrosome of animals has a pair of.... |
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Definition
| centrioles at the center, but the function of the centrioles is somewhat undefined. |
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Term
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Definition
| chromosome number by copying the chromosomes once, but dividing twice. |
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Term
| the first division meiosis I separates... |
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Definition
| homologous chromosomes. The second meiosis II, separates sister chromoatids. |
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Term
| division in meiosis I occurs in _____ phases: name them |
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Definition
| 4; prophase, metaphase, anaphase, and telaphase. |
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Term
| during the preceding interphase the chromosomes are... |
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Definition
| replicatdd to form sister chromatids. These are genetically identical and joined at the centromere. Also, the single centrosome is replicated. |
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Term
| in prophase I, the chromosomes condense and.... |
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Definition
| homologous chromosomes pair up to form tetrads. In a process called synapsis, special proteins attach homologous chromosmes tightly together. |
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Term
| at several sites the chromatids of homologous chromosomes are.... |
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Definition
| crossed (chiasmata) and segments of the chromosomes are traded. |
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Term
| a spindle forms from each centrosome and spindle fibers attach to... |
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Definition
| kinetochores on the chromosomes begin to move the TETRADS around |
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Term
| at metaphase I, the tetrads are all... |
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Definition
| arranged at the metaphase plate. Microtubules from one pole are attached to the kinetichore of one chromosome of each tetrad, while those from the other pole are attached to the other. |
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Term
| In anaphase I, the homologous chromosomes.... |
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Definition
| separate and are pulled toward opposite poles. |
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Term
| In telophase I, movement of homologous chromosomes... |
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Definition
| continue until there is a haploid set at each pole. EACH CHROMOSOME CONSISTS OF LINKED SISTER CHROMATIDS. |
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|
Term
| cytokinesis by the same mechanisms as mitosis usually..... |
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Definition
| occur spontaneously. In some species, nuclei may reform but there is no further replication of chromosomes. |
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Term
| Meiosis II is very similar to.... |
|
Definition
| mitosis. During prophase II a spindle apparatus forms, attaches to kinetochores of each sister chromatids, and moves them around. |
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Term
| spindle fibers from one pole attach to the kinetochore of one sister chromatid and... |
|
Definition
| those of the other pole to the other sister chromatid. |
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Term
| at metaphase II, the sister chromateds are... |
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Definition
| arranged at the metaphase plate. The kinetochores of sister chromatids face opposite poles. |
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Term
| at anaphase II, the centromeres of sister chromatids.... |
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Definition
| separate and the now separate sisters travel toward opposite poles. |
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Term
| in telophase II, separated sister chromatids... |
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Definition
| arrive at opposite poles. Nuclei from around the chromatids. Cytokenisis separates the cytoplasm. At the end of meiosis, there are four haploid daughter cells. |
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Term
| mitosis and meioisis have several key differences... three are |
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Definition
| the chromosome number is reduced by half in meiosis but not in mitosis. Mitosis produces daughter cells that are genetically identical to the parent and to each other. Meiosis produces cells that differ from the parent and each other. |
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Term
| first of three events unique to meiosis, occuring during the first division cycel. |
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Definition
| during prophase I, homologous chromosomes pair up in a process called synapsis. |
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Term
| during synapsis... 3 things |
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Definition
| a protein zipper, the synaptonemal complex, holds homologous chromosomes together tightly. later in prophase I, the joined homologous chromosomes are visible as a tetrad. at x-shaped regions called chiasmata sections of non-sister chromatids are exchanged. |
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Term
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Definition
| is the physical manifestation of crossing over a form of genetic rearrangement. |
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Term
| 2/3 of unique meiosis during first division cycle |
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Definition
| at metaphase I homologous pairs of chromosomes, not individual chromosomes are aligned along the metaphase plate. In humans, you would see 23 tetrads. |
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Term
| 3/3 of unique meiosis during first division cycle |
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Definition
| at anaphase I, it is homologous chromosomes, not sister chromatids, that separate and are carried to oposite poles of the cell. Sister chromatids remain attached at the centromere until anaphase II. |
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Term
| mitosis production vs. meiosis production.... |
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Definition
| mitosis produces two identical daughter cells while meiosis produces 4 very different cells. |
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Term
| in a typical breeding experiment, mendesl would.... |
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Definition
| cross-pollinate (hybridize) two contrasting, true breeding pea varieties. |
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Term
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Definition
| the true-breeding parents |
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Term
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Definition
| the hybrid offspring of P generation |
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Term
| mendel would then allow the F1 hybrids to self-pollinate to produce... |
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Definition
| an F2 generation (monohybrid) |
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Term
| by the law of segregation the two alleles for a characters are packaged into... |
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Definition
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Term
| when mendel allowed the F1 plants to self-fertilize, the F2 generation... |
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Definition
| included both purple-flowered and white-flowered plants. The whit trait, absent in F1, reappeared in the F2. |
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Term
| 1/4 ideas of mendelian hypothesis |
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Definition
| alternative version of allele (gene) account for variations in inherited characters. Different alleles vary somewhat in the sequence of nucleotides at the specific locus of a gene. |
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Term
| 2/4 ideas for mendelain hypothesis |
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Definition
| for each character, an organism inherits two alleles, one from each parent. A diploid organism inherits one set of chromosomes from each parent. Each diploid organism has a pair of homologous chromosomes and therefore two copies of each locus. |
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Term
| 3/4 idea of mendelian hypothesis |
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Definition
| if two alleles differ, then one, the DOMINANT ALLELE, is fully expressed in the organisms' appearance. The other, the RECESSIVE ALLELE, has no noticeable effect on the organism's appearance. |
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Term
| 4/4 idea of mendelian hypothesis |
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Definition
| the two alleles for each character segregate (separate) during gamete production (during meiosis). If different alleles are present, then 50% of the gametes will recieve one allele and 50% will recieve the other. |
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Term
| the separation of alleles into separate gametes is summarized as.. |
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Definition
| Mendel's law of segregation |
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Term
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Definition
| predicts the results of a genetic cross between individuals of known genotype |
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Term
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Definition
| an organism with two identical alleles for a character (PP) |
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Term
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Definition
| organisms with two different alleles for a character (Pp) |
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Term
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Definition
| a description of an organism's traits |
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Term
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Definition
| a description of an organisms genetic makeup. two organisms can have the same phenotype but have different genotypes if one is homozygous dominant and the other is heterozygous. |
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