what is the functions of the centrosome?
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In mitosis the nuclear membrane breaks down and the centrosome nucleated mictrotubules can interact with the chromosomes to build the mitotic spindle. The centrosome nucleates and organizes microtubules. It plays a central role in mitosis, and in making cilia and flagella.\n\nInterestingly, centrosomes are not required for the progression of mitosis. When the centrosomes are irradiated by laser, mitosis proceed normally with a morphologically normal spindle. However, acentrosomal cells lack radial arrays of astral microtubules. They are also defective in spindle positioning and cytokinesis. The function of centrosome in this context seemed to ensure the fidelity of cell division, rather than directing it. Cells that have lost their centrosomes arrest in the following cell cycle. It is not yet clear whether this is because the centrosome plays a role in cell cycle progression or whether the arrest is the result of a generic stress response.\n\nWhen the nematode C. elegans egg is fertilized the sperm delivers a pair of centrioles. These centrioles will form the centrosomes which will direct the first cell division of the zygote and this will determine its polarity. It is not yet clear whether the role of the centrosome in polarity determination is microtubule dependent or independent.
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Plant cells do not use centrioles in mitosis, many don't even use centrosomes! Despite this lack of centrosomes and centrioles, these plant cells are still able to bundle and organize their microtubules into a spindle. How plant cells are able to do all this is not clear, but this is also what is seen in meiotic divisions in animal cells, such as in the early divisions in mouse embryonic cells.
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nuclear membrane protects the nucleus and chromosomes.During cell division if the nuclear membrane is intact, the chromosomes and chromatid formation cannot be possible in the limited place.\nEven for the formation and movement of polar fibers or spindle fibers nuclear membrane is a obstacle to reach the chromosomes.\nAlthough the nuclearmembran breaks down in the late pro phase , it develops again in telopphase.
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Organelles\nMain article: Organelle \nThe human body contains many different organs, such as the heart, lung, and kidney, with each organ performing a different function. Cells also have a set of "little organs," called organelles, that are adapted and/or specialized for carrying out one or more vital functions. Membrane-bound organelles are found only in eukaryotes.\n\nCell nucleus (a cell's information center)  \nThe cell nucleus is the most conspicuous organelle found in a eukaryotic cell. It houses the cell's chromosomes, and is the place where almost all DNA replication and RNA synthesis occur. The nucleus is spheroid in shape and separated from the cytoplasm by a double membrane called the nuclear envelope. The nuclear envelope isolates and protects a cell's DNA from various molecules that could accidentally damage its structure or interfere with its processing. During processing, DNA is transcribed, or copied into a special RNA, called mRNA. This mRNA is then transported out of the nucleus, where it is translated into a specific protein molecule. In prokaryotes, DNA processing takes place in the cytoplasm. \nRibosomes (the protein production machine)  \nRibosomes are found in both prokaryotes and eukaryotes. The ribosome is a large complex composed of many molecules, including RNAs and proteins, and is responsible for processing the genetic instructions carried by an mRNA. The process of converting an mRNA's genetic code into the exact sequence of amino acids that make up a protein is called translation. Protein synthesis is extremely important to all cells, and therefore a large number of ribosomes — sometimes hundreds or even thousands — can be found throughout a cell. \nMitochondria and Chloroplasts (the power generators)  \nMitochondria are self-replicating organelles that occur in various numbers, shapes, and sizes in the cytoplasm of all eukaryotic cells. As mitochondria contain their own genome that is separate and distinct from the nuclear genome of a cell, they play a critical role in generating energy in the eukaryotic cell, a process involving a number of complex metabolic pathways. Chloroplasts are larger than mitochondria, and convert solar energy into a chemical energy ("food") via photosynthesis. Like mitochondria, chloroplasts have their own genome. Chloroplasts are found only in photosynthetic eukaryotes, like plants and algae. There is a number of plant organelles that are modified chloroplasts; they are broadly called plastids, and are often involved in storage. \nEndoplasmic reticulum and Golgi apparatus (macromolecule managers)  \nThe endoplasmic reticulum (ER) is the transport network for molecules targeted for certain modifications and specific destinations, as compared to molecules that will float freely in the cytoplasm. The ER has two forms: the rough ER, which has ribosomes on its surface, and the smooth ER, which lacks them. Translation of the mRNA for those proteins that will either stay in the ER or be exported from the cell occurs at the ribosomes attached to the rough ER. The smooth ER is important in lipid synthesis, detoxification and as a calcium reservoir. The Golgi apparatus, sometimes called a Golgi body or Golgi complex is the central delivery system for the cell and is a site for protein processing, packaging, and transport. Both organelles consist largely of heavily-folded membranes. \nLysosomes and Peroxisomes (the cellular digestive system)  \nLysosomes and peroxisomes are often referred to as the garbage disposal system of a cell. Both organelles are somewhat spherical, bound by a single membrane, and rich in digestive enzymes, naturally-occurring proteins that speed up biochemical processes. For example, lysosomes can contain more than three dozen enzymes for degrading proteins, nucleic acids, and certain sugars called polysaccharides. Here we can see the importance behind compartmentalization of the eukaryotic cell. The cell could not
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or·gan·elle  (ôrg-nl)\nn.\nA differentiated structure within a cell, such as a mitochondrion, vacuole, or chloroplast, that performs a specific function.\n\ncell wall\nn.\nThe rigid outermost cell layer found in plants and certain algae, bacteria, and fungi but characteristically absent from animal cells.\n\ncell membrane\nn.\nThe semipermeable membrane that encloses the cytoplasm of a cell. Also called cytomembrane, plasmalemma, plasma membrane.\n\nnu·cle·us  (nkl-s, ny-)\nn. pl. nu·cle·i (-kl-) or nu·cle·us·es \n1. A central or essential part around which other parts are gathered or grouped; a core: the nucleus of a city.\n2. Something regarded as a basis for future development and growth; a kernel: a few paintings that formed the nucleus of a great art collection.\n3. Biology A large, membrane-bound, usually spherical protoplasmic structure within a living cell, containing the cell's hereditary material and controlling its metabolism, growth, and reproduction.\n4. Botany \na. The central kernel of a nut or seed.\nb. The center of a starch granule.\n5. Anatomy A group of specialized nerve cells or a localized mass of gray matter in the brain or spinal cord.\n6. Physics The positively charged central region of an atom, composed of protons and neutrons and containing almost all of the mass of the atom.\n7. Chemistry A group of atoms bound in a structure, such as a benzene ring, that is resistant to alteration in chemical reactions.\n8. Astronomy \na. The central portion of the head of a comet.\nb. The central or brightest part of a nebula or galaxy.\n9. Meteorology A particle on which water vapor molecules accumulate in free air to form a droplet or ice crystal.\n10. Linguistics The part of a syllable having the greatest sonority. In the word middlemost (mdl-mst) the nuclei of the three syllables are (), (l), and (); in the Czech word krk ("neck"), the nucleus is (r).\n\ncy·to·plasm  (st-plzm)\nn.\nThe protoplasm outside the nucleus of a cell.
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Mitosis is the process of cell division.  Our cells are constantly dying off.  Mitosis allows living organisms to continue to survive by replacing the dying cells.
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It is semi-permeable and controls what substances enter and leave the cell. It allows certain substances such as amino acids, glucose, mineral salts, water etc to enter the cell and also allows other substances like enzymes or waste products (carbon dioxide, urea) to leave the cell. This helps to maintain a suitable environment in the cell for it to survive and carry out its functions properly.
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mitosis:the process in cell division by which the nucleus divides, typically consisting of four stages: prophase, metaphase, anaphase and telophase.\n\nmeiosis: (genetics) cell division that produces reproductive cells in sexually reproducing organisms; the nucleus divides into four nuclei each containing half the chromosome number (leading to gametes in animals and spores in plants) \n\nosmosis:Transmission of fluids from one cell into another; foundation of metabolism, led by the concentration of salt within a cell. Water can penetrate cell membranes, and strives to, where the concentration of salt is highest, in order to equalize the salt concentration in the body.
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1. amnionic membrane, contains, pressure, shock, movement, temperature\n2. planceta\n\nFunction of the Planceta\n1. oxygen, nutrients\n2. wastes (like carbon dioxide)\n3. can't rmeber this one sorry\n4. plancenta does that
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I do not know alot about them, but I do know that spindle proteins are used in cell division to move the chromatids.\n\nSee http://www.scienceaid.co.uk/celldivision.html for more about cell division and spindle proteins.
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The cytoplasm containing the other cell parts.
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Their function in the body. For instance, cells that require a lot of communication between them and the outside have a lot of transmembrane proteins that others that are more "isolated".
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The main function of chloroplast is to absorb sunlight in order for photosythesis to take place. The chloroplast consists of many thylakoids that contain a photosynthetic pigment called chlorophyll. The photons from the light react with this chlorophyll in the chloroplast to give rise to photosynthesis.\n\nHope that helps!
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(for animal cells..)\n1. non-kinetochore microtubules lengthen. this elongates the cell even more than before.\n2. pairs of sister chromosomes attach at opposite ends of the cell.\n3. new nuclear envelopes form around the two sets of dna at the opposite ends of the cell.\n4. cytokinesis (division of cytoplasm) occurs and the plasma membrane re-forms around the two daughter cells.
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They pull the chromosomes and then drag them to the  poles.\nThis happens by depolymerisation of the tubulin units that constitute the spindle fibres.The role of centriole is to provide anchorage and give  direction to the chromosomes as to which direction and angle they will go to.
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During *mitosis*, the cytoplasm of a cell and its organelles separate into two new *identical cells*?\n\nI'm not sure what else you're looking for here...
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Mitosis is the process of dividing a parent cell to make two daughter cells.\nFirst the Centrioles move to the opposite sides of the cell\nthe nuclear membrane dissolves, and the spindle fibers begin to form.(Prophase)\nSecond the chromosomes line up in the center of the cell.(Metaphase)\nThird the centromere breaks up and the spindle fibers pull apart the chromosomes.(Anaphase)\nFourth the nuclear membranes begin to reform, and the nucleus is formed on each cell.(Telophase)\nFinally the cellular membrane separate and 2 daughter cells are formed.(Cytokinises)