why phaeophytin happen?
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You should find the answer you seek here...\nhttp://www.biology.lsa.umich.edu/~gwk/teaching/limno/lab/onlinemanual/chlorophyll.html\nhere...\nhttp://www.steve.gb.com/science/natural_selection.html\nhere...\nhttp://plankt.oxfordjournals.org/cgi/content/abstract/24/11/1221\nor here...\nhttp://en.wikipedia.org/wiki/Phaeophytin
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Thie sperm is not lik epollen which is easliy transmitted by wind, and they have no natural polinators. Ferns evolved when the earths atmosphere was very humid and that allowed for them to use the motile sperm to swim through the water in the enviroment to fertilize the eggs of the plant. Ferns are also primitive plansts so you can expect them to have some characterisitics of plants that were typically marine due to evolving from them. (marine plants were some of the most primitive.)
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I did an experiment with this in graduate school.  When a plant has limited to no light, it invests all of its energy and growth into finding a light source.  In my experiment, the plant grew very tall and had very few leaves (since it could not go through photosynthesis anyway, why bother).  It was a very interested experiment and proved that even plant have priorities.
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plants on land have a harder time spreading out their young, look at pollen and seeds.  water plants just release their gametes and they float away
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As cells grow the surface area/volume ratio goes down.  This inhibits their ability to uptake nutrients.
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They think it was algae.
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Isn't it that besides the fact that the chloropyll portraits the green pigment, they're also the ones which collect solar energy? So, basically, because they're the collectors of solar energy, why would they burn? there' nothing in it that would make it react since it is the storage of the light.
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Kelp is a great example of a multicellular algae (which is protist), like the "kelp forests" in Alaska.  Check it out.\n\nhttp://www.oceanlight.com/html/kelp.html
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Cyanobacteria can use sunlight or organic materials to survive, while algae must have sunlight.
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remember the phases in meiosis (in order) :Prophase, Metaphase, anaphase, telephase (pmat)\nMitosis\nI  INTRODUCTION \n\nMitosis, process in which a cell’s nucleus replicates and divides in preparation for division of the cell. Mitosis results in two cells that are genetically identical, a necessary condition for the normal functioning of virtually all cells. Mitosis is vital for growth; for repair and replacement of damaged or worn out cells; and for asexual reproduction, or reproduction without eggs and sperm.\n\nAll multicellular animals, plants, fungi, and protists, which begin life as single cells, carry out mitosis to develop into complex organisms containing billions of cells. Mitosis continues in full-grown organisms as a means of maintaining the organism—replacing dying skin cells, for example, or repairing damaged muscle cells. In the cells of the adult human body, mitosis occurs about 25 million times per second. Multicellular organisms such as sea stars, sea anemones, fungi, and certain plants rely on mitosis for asexual reproduction at particular stages in their life cycles, and mitosis is the sole mode of reproduction for many single-celled organisms.\n\nII  INTERPHASE \n\nThe life cycle of eukaryotic cells, or cells containing a nucleus, is a continuous process typically divided into three phases for ease of understanding: interphase, mitosis, and cytokinesis. Interphase includes three stages, referred to as G1, S and G2. In G1, a newly formed cell synthesizes materials needed for cell growth. In the S stage, deoxyribonucleic acid (DNA), the genetic material of the cell, is replicated. At this stage, DNA consists of long, thin strands called chromatin. As each strand is replicated, it is linked to its duplicate by a structure known as a centromere. When the S stage is complete, the cell enters a brief stage known as G2, when specialized enzymes correct any errors in the newly synthesized DNA, and proteins involved with the next phase, mitosis, are synthesized. \n\nIII  MITOSIS \n\nMitosis occurs in four steps. In prophase the replicated, linked DNA strands slowly wrap around proteins that in turn coil and condense into two short, thick, rodlike structures called chromatids, attached by the centromere. Two structures called centrioles, both located on one side of the nucleus, separate and move toward opposite poles of the cell. As the centrioles move apart, they begin to radiate thin, hollow, proteins called microtubules. The microtubules arrange themselves in the shape of a football, or spindle, that spans the cell, with the widest part at the center of the cell and the narrower ends at opposite poles. As the spindle forms, the nuclear membrane breaks down into tiny sacs or vesicles that are dispersed in the cytoplasm. Final disintegration of the membrane marks the beginning of metaphase. \n\nIn metaphase, the spindle fibers attach to the chromatids near the centromeres, and tug and push the chromatids so that they line up in the equatorial plane of the cell halfway between the poles. Like two individuals standing back to back at the equator, one chromatid faces one pole of the cell, and its linked partner faces the opposite pole. This precise orientation is necessary in order for the next step, anaphase, to occur. Anaphase begins when the centromeres split, separating the identical chromatids into single chromosomes, which then move along the spindle fibers to opposite poles of the cell. \n\nAs these two identical groups of single chromosomes gather at opposite poles of the cell, telophase begins. A new nuclear membrane forms around each new group of chromosomes. The spindle fibers break down and the newly formed chromosomes begin to unwind. If viewed under a light microscope, the chromosomes appear to fade away. They exist, however, in the form of chromatin, the extended, thin strands of DNA too fine to be seen except with electron microscopes. Mitosis accomplishes replication and division of the nucleus,
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I'm not really sure what they are looking for.  There are many different results that can occur.  It also depends on how much of the plant is cut and removed, when in the plants life cycle you make the cut, which part of the plant you cut off, etc.  I would guess that they are looking for a difference in vertical shoot growth.  If the apical (the top of the main stem) meristem is removed this will cause lots of lateral growth and branching.  This happes because the auxin hormone is no longer able to go to the apical meristem so it it activates lateral bud growth.  Another thing that might happen depending on plant type is that you might get sucker growth.  This happens when too much of the photosynthetic material is removed.  The roots then start to send up suckers which are new stems growing off of the existing root system.  This is most common in trees and will only happen in woody plants.
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It appears that one side of the phospholipid is attracted to the water, while the other side is repelled by the water.\n\n"Amphipathic phospholipids will form an artificial membrane on the surface of water with only the hydrophilic heads immersed in water (Langmuir, 1917). \n\nAmphipathic = Condition where a molecule has both a hydrophilic region and a hydrophobic region. \n\nDeduction: Because of their molecular structure, phospholipids can form membranes."
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Algae provide food and oxygen for many creatures that live in the same environment. Some examples of algae are seaweed and pond scum. However, in intense algae blooms due to nitrogen run off from farms, a plant fertilizer that cause the algae to grow out of control it leads to oxygen depletion in the water known as hypoxia. When the algae die off bacteria attack the algae and use up all the oxygen. It is a delicate balance.
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phycobilins are the pigment  present in rhodophyta (red algae belongs to the rhodophyta and agra produced  by certain red algae .the main  sources of agar-agar is the thalli of gelidium,gracilaria andGigartina ,campylaephora,eucheuma ,hypea,ahnfelhia,and frucella)\nPHYCOBILINS:-phycobilinns are Water-soluble photosynthetic pigments found in the cytoplasm, or in the stroma of the chloroplast. There are two classes of phycobilins and they occur only in Cyanobacteria and Rhodophyta. The bluish pigment phycocyanin is found in Cyanobacteria and gives them their common name of "blue-green algae". The reddish pigment phycoerythrin is found only in Rhodophyta and gives them their common name of "red algae".\n\nPhycobilins are not only useful to the organisms which use them for soaking up light energy; they have also found use as research tools. Both pycocyanin and phycoerythrin fluoresce at a particular wavelength. That is, when they are exposed to strong light, they absorb the light energy, and release it by emitting light of a very narrow range of wavelengths. The light produced by this fluorescence is so distinctive and reliable, that phycobilins may be used as chemical tags. The pigments are chemically bonded to antibodies, which are then put into a solution of cells. When the solution is sprayed as a stream of fine droplets past a laser and computer sensor, a machine can identify whether the cells in the droplets have been tagged by the antibodies. This has found extensive use in cancer research, for tagging tumor cells. \nOrganisms belonging to the Division Rhodophycota of the Kingdom Protista. Most of the over 4000 species are marine. They range in complexity from simple unicellular organisms to unbranched and branched filaments to complex multiaxial uprights and crusts. Their pigments include chlorophyll a and the phycobiliproteins, red phycoerythrin (often the dominant pigment) and blue phycocyanin, as well as carotenes, lutein, zeaxanthin. Phycoerythin reflects red light and absorbs blue light. Because blue light penetrates water to a greater depth than light of longer wavelengths, these pigments allow red algae to photosynthesize and live at somewhat greater depths than most other algae. Some rhodophytes have very little phycoerythrin, and may appear green or bluish from the chlorophyll and other pigments present in them. Most red algae have a complex life history with three phases: tetrasporophyte, gametophyte, and carposporophyte. \nAGAR AGAR:-\nAgar is an unbranched polysaccharide obtained from the cell walls of some species of red algae or seaweed. The word agar comes from the Malay word agar-agar (meaning jelly). It is also known as kanten or agal-agal (Ceylon agar). Chemically, agar is a polymer made up of subunits of the sugar galactose. Agar polysaccharides serve as the primary structural support for the algae's cell walls. Dissolved in hot water and cooled, agar becomes gelatinous. Its chief use is as a culture medium for microbiological work. Other uses are as a laxative, a vegetarian gelatin substitute, a thickener for soups, in jellies, ice cream and Japanese desserts such as anmitsu, as a clarifying agent in brewing, and for paper sizing fabrics.Nutrient agar is used throughout the world as a medium for the growth of bacteria and fungi, but not viruses (however, viruses are often grown in bacteria that are growing on agar). Though less than 1% of all existing bacteria can be grown successfully, the basic agar formula can be used to grow most of the microbes whose needs are known. More specific nutrient agars are available, because microbes can be picky. For example, blood agar, which is generally combined with horse blood, can be used to detect the presence of haemorrhagic micro-organisms such as E.coli O:157 H:7. The bacteria digest the blood, turning the plate clear.Agar is a heterogeneous mixture of two classes of polysaccharide: agaropectin and agarose [1]. Although both polysacchari
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the same as why hair turns Grey the cells that produce the brown pigment stop working as well as when you are young or it could be a cataract
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My co-worker told me its because the bodies take longer to start to turn.  Pigment and such.
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There are many hundreds of thousands of species of unicellular algae that reproduce sexually. \n\nWe have some fossils of brown algae that were in the process sexually reproducing dating back to well before the first multicellular life evolved. We know this because such alage produce silicons 'skeletons' that preserved their structure. \n\nSo we can be absolutely certain that the first sexually reproducing organisms weren't multicellualr.\n\nAs for which the first were, we really can not know. It's almost impossible to tell from fossils whether how a unicellular organism reproduced if it doesn't produce a solid skeleton, and solid skeletons evolved late.