1.\n(a)what are the three parts of the cell theory?!\n(b)why was development of the cell theory important for progress in science?!
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ya right..but ilike to give some points\n\nCell theory is a scientific theory that is one of the foundations of biology. The generally accepted parts of cell theory include:\n\nThe cell is the fundamental unit of structure and function in living things. \n\nAll organisms are made up of one or more cells. \nCells arise from other cells through cellular division. \nCells carry genetic material passed to daughter cells during cellular division. \nAll cells are essentially the same in chemical composition. \nEnergy flow (metabolism and biochemistry) occurs within cells. \n\nIn 1838, the botanist Matthias Jakob Schleiden and Theodor Schwann, a physiologist discovered that both plant and animal cells had nuclei\n\nSchwann and Schleiden's statement of the cell theory was:\n\nCells are the unit of structure, physiology, and organization in living things. \nCells are both a distinct entity and a building block in the construction of organisms. \nCells form by spontaneous generation. \n\nWhen abiogenesis was later disproven, the third tenet was changed to state that all cells came from existing cells. The correct interpretation of cell formation by division was finally promoted by others and formally enunciated in 1858 in Rudolph Virchow's powerful dictum, "Omnis cellula e cellula"... "All cells only arise from pre-existing cells".\n\n\ngo here http://fig.cox.miami.edu/~cmallery/150/unity/cell.text.htm
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1. c\n2. d\n3. e\n4. b\n5. a\nIts been a few years since I took biology but I thought I could take a shot at your question.  Hope the answers are right:)
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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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Two or more atoms make a molecule\nMillions and millions of molecules make up a cell.
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I am a scientist.  I am trained in hematology, not physics, though I have a good understanding of many principles, and I love exploratory thought processes.  If you want to shoot me a line, I have connections at the Ferme lab in Ohio (if it goes anywhere), and, of course, I'd be personally interested to hear it.\n\nianklansek@yahoo.com
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Answer = A\n\nA larger cell (answer B) can hold more charged particles, but a small cell with 5 charged particles will have the same potential as a large cell with 5 charged particles!\n\n(C) and (D) relate to how quickly the cell can re-creat the resting membrane potential once, say, an action potential has passed through the nerve.
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D. Binary Fission\n\nDont you just love biology? :) Hah.
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Great stuff going on right now having to do with developmental genes (like Hox genes).  You may know this as "Evo Devo" or evolutionary developmental biology.\n\nCheck out the book "Endless Forms Most Beautiful," by Sean Carroll.  He also gives ideas for research and new fields, lots of peer-reviewed papers.\n\nI just read it this Fall, it was great.
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question 1-b\nquestion 2-c
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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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Evolution doesn't happen, one species doesn't evolve into another species.\nIn Darwin's time, scientists thought cells were just blobs of protoplasm. Since that time the advance of science has uncovered ever more powerful evidence that what Christians believe is true on all levels, including the natural world. And that is becoming even clearer today as scientists learn more about what is inside the cell-and especially the structure of DNA.\n\nAccording to cell biologist Bruce Alberts, president of the National Academy of Sciences, "The entire cell can be viewed as a factory that contains an elaborate network of interlocking assembly lines, each of which is composed of a set of large protein machines."\n\nEven the simplest cells are bristling with high-tech machinery. On the outside, their surfaces are studded with sensors, gates, pumps and identification markers.\n\nInside, cells are jam-packed with power plants, automated workshops and recycling units. Miniature monorails whisk materials from one location to another. No such system could arise in a blind, step-by-step Darwinian process.\n\nThe most advanced, automated modern factory, with its computers and robots all coordinated on a precisely timed schedule, is less complex than the inner workings of a single cell.\n\n"A bacterium is far more complex than any inanimate system known to man. There is not a laboratory in the world which can compete with the biochemical activity of the smallest living organism. One cell is more complicated than the largest computer that man has ever made." - Sir James Gray, from Cambridge University\n\nDNA is like a language in the heart of the cell, a molecular message, a set of instructions telling the cell how to construct proteins-much like the software needed to run a computer. Moreover, the amount of information DNA includes is staggering: A single cell of the human body contains three or four times more information as all 30 volumes of the Encyclopedia Britannica. As a result, the question of the origin of life must now be redefined as the question of the origin of biological information. Can information arise by natural forces alone? Or does it require an intelligent agent?\n\nDNA is composed of ordinary chemicals (bases, sugars, phosphates that react according to ordinary laws. What makes DNA function as a message is not the chemicals themselves but rather their sequence, their pattern. The chemicals in DNA are grouped into molecules (called nucleotides) that act like letters in a message, and they must be in a particular order if the message is going to be intelligible. If the letters are scrambled, the result is nonsense. So the crucial question is whether the sequence of chemical "letters" arose by natural causes or whether it required an intelligent source. Is it the product of law or design?\n\nSince DNA contains information, the case can be stated even more strongly in terms of information theory, a field of research that investigates the ways information is transmitted. The naturalistic scientist has only two possible ways to explain the origin of life-either chance or natural law. But information theory provides a powerful tool for discounting both of these explanations. Both chance and law lead to structures with low information content, whereas DNA has a very high information content."\n\nThe sequence of basis in DNA can not be explained by natural law because there are no chemical laws that make any sequence more likely than another. At the same time these sequences are so complicated that they can not be explained by chance.\n\n"Based on probability factors any viable DNA strand having over 84 nucleotides cannot be the result of haphazard mutations. At that stage, the probabilities are 1 in 4.80 x 10. Such a number, if written out, would read: \n\n480,000,000,000,000,000,000, 000,000,000,000,000, 000,000,000,000,000. \n\n"Mathematicians agree that any requisite number
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I would do something like this:\n\n* Similarities and differences among living organisms\n(For example, the characteristics of life, cells, comparing single and multicellular organisms)\n*Homeostasis in living things\n(Basic biochemical processes, Feedback systems, Disease)\n*Genetics\n(Heredity, Genes)\n*Reproduction and development\n(Cell division, reproduction among organisms)\n*Evolution\n(Theories)\n*Ecology\n(Interaction between organisms and their environments, energy flow)\n\nThese are just a few ideas.
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G1 - chromatin\nS - chromosomes\nG2 - chromatin\nMitosis - chromosomes (the chromosomes become less condensed in telophase though)\nCytokinesis - chromatin\n\nDuring all three subphases, the cell grows by producing protiens and cytoplasmic organelles such as mitochondria and endoplasmic reticulum.  However, chromosomes are duplicated only during the S phase.  Thus, a cell grows (G1), continues to grow as it copies its chromosomes (S), grows more as it completes preparations for cell division (G2), and divides (M).  I'm guessing cell growth is fastest in G1 but im not sure, so dont quote me.\nHope I helped =)
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Yes.  The term'subcellular" would just mean it is comprised of peices smaller than a cell.\n\nThe term 'components' is simply a word for parts used for assembly.  \n\nMost of these parts are an integral part of the cell, meaning if you get rid of them you lose the cell.
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right on, I'm glad someone else sees some of the problems with evolutions.  Everyone else, keep in mind that this protein is just one of millions that is vital to life as we know it.  And another thing how do we know that the world is 4 billion years old?  Carbon dating?  The half life of carbon 14 is 5,730 years.  So how many half lives is that. Simply put by 4 billion years there no carbon 14 left to measure, it would have all deteriorated.  There is no way that all the life on earth could have resulted by evolution\n\nOkay to everyone above, to the person who said that scientists have created living cells from nonliving molecules, slap yourself because that is an absolute falsehood.  Next when you say that scientist created amino acids that is true but lets look closer.  There were only about 5 different amino acids that were created not all the ones that are necessary for life.  Next how were all the other cell parts (lipids, nucleic acids, carbs) formed.  Did they just appear? Scientists cannot make lipids from just the molecules needed to synthesize them.  I have a very hard time believing that all these parts were formed, in the same place (it is very hard to keep things together underwater let alone in an ocean) and somehow all came together and then replicated.  No that does not happen.  \n\nNext how did new material get added in to the gene pool? Mutation?  Well everything that we know from science (Medicine, genetics) tells us that mutation is bad.  Name one good mutation.  Not sickle cell anemia.  First of all sickle cell is only beneficial when it is in the heterozygote and so it helps protect against malaria, it also cause way more harmful symptoms than beneficial ones.  Look at what happens with people that have cystic fibrosis.  There are a few (less than 10) nucleic acid changes and it is usually fatal.  Mutation does not, repeat, DOES NOT, provide helpful change.  Another thing is how did this first cell survive?  Even the simplest cell carry out complex reactions, and processes that "Scientists" cannot explain after years of study.  In order for this "first cell" to be viable all these pathways would have to present before the cell could live.  And what about all the proteins need for DNA/RNA replication?  There are about 150 different proteins that carry out karyokinesis alone and then comes the problem of separating the DNA.  Come on do you still think that all this could have happened by chance?  \n\nNext time, do not come after creationist because you do not want to believe that there is a God.  With creation everything fits.  The more you know about biology the more you see the holes in evolution.
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The first cell "must" divide only once but "may" divide almost without end during the life of a creature.  When the first cell divides its DNA splits like cutting the rungs of several (helical) ladders (genes) and each ladder half then regenerates its missing half in the new cells.  After the split, which is the original cell?  If one of the two "new" cells died prematurely, the remaining cell would likely carry on.  After only a few cell divisions, cells differentiate and become specialized and no longer are capable of producing all the tissue types required.  The original cell is lost for practical purposes.
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The six characteristics of living things, and an explanation of each one. \nTheme #1 - Cells \n\nAll living things are composed of one or more cells. Different types of cells have different "jobs" within the organism. Each life form begins from one cell, which then will split. These cells split, and so on. After this has happened several times, differentiation is undergone, when the cells change so that they are not the same thing anymore. Then they are used to begin to put together the final organism, some cells, for example, as the eyes, some as the heart, etc. The only arguable exception to this is viruses. They are not composed of cells, but are said to be "living." \nTheme#2 - Organization \n\n \nComplex organization patterns are found in all living organisms. They arrange themselves on very small levels, grouping like things together. On larger levels, they become visible. This also has to do with differentiation, as the cells are organized in a manner that makes sense for the organism after they change to what they’ll be in the final organism. \n\nTheme#3 - Energy Use \n\nAll organisms use energy. The sum of the chemical energy they use is called metabolism. This energy is used to carry out everything they do. Autotrophs (plants) use energy from the sun for photosynthesis, to make their own ‘food’ (glucose). Heterotrophs (animals and humans) must ingest food for this purpose. \n\n\nTheme#4 - Homeostasis \n\nAll organisms have stable internal conditions which must be maintained in order to remain alive. These include temperature, water content, heartbeat, and other such things. In a way, this has to do with energy use, because a certain level of energy must be kept within the body at all times. For this, obviously, humans must then ingest food on a regular basis. Not all conditions are for the body to maintain itself; though most are. \n\n\nTheme#5 - Growth \n\nAll organisms grow and change. Cells divide to form new, identical cells. Differentiation happens, as well, when cells mutate into other types of cells, making a more complex organism. Organisms growing, changing, and becoming more complex is called development. Single-celled organisms do grow as well, but they will only become slightly larger – this is nearly unmeasurable. \n\n\nTheme#6 - Reproduction \n\nAll organisms reproduce in order to continue the species' life. This is combining genetic information (in sexual reproduction) or splitting into two organisms (in asexual reproduction) in order to create another of the same species. In sexual reproduction, the new organism will have some characteristics from the mother, and some from father. It may look like either of them, or it may not. In asexual reproduction, the new organism is an exact copy of the first. Sometimes, not every member of a species is able to reproduce. As long as others are (which we know they can, if they still exist today) then it does not threaten the species. (Except for mules, but don't worry about them, they are a bizarre anomoly.)