1. The genetic constitution of all cells of an organism are identical.\n2. Error accumulation in the DNA leads to ageing.\n\nOf 1 and 2, which is true.\nBoth cannot be true.
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Neither is true.  In a broad sense #1 is true, but every time a cell divides errors accumulate.  So every cell has a unique signature, but it may only be one base pair difference in 3 billion.  #2 is not true either, error accumulation leads to diseases like cancer (mostly cancer).  Aging is thought to occur by telomere shortening. Every time a cell replicates, the telomere shortens.  It can be repaired by telomerase, but in some cases telomerase is not active.  When it gets too short the chromosome can stick to another chromosome, leading to aneuplody.  Once the telomere gets short, the cell enters crisis.  Two things can happen; one is that the cell dies.  Two is that the cell becomes immortalized, which is the next step on the road to cancer.\n\nPS DNA damage does not cause AIDS!
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Mutations occur at times to protect the species and at times just because the chromosomes don't split correctly.  A good example is sickle cell trait which protects against malaria in the tropics but causes major health problems when it becomes the disease.  Mutations are scientifically proven.  Evolution is still a theory.  Commonality in genes does not imply a common ancestor, it implies a genetic system that works.  Maybe everything appeared at once.  There is proof of a worldwide flooding that changed the earth permanently.  The carbon dating that is used for "proving" the age of fossils is notoriously inaccurate and how in the world can anyone prove the age of something more than a few hundred years?  Evolution is a THEORY. It is not possible to prove it whereas mutations have been detected in nature in an ongoing way.
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An egg, and a sperm both contain a nucleus which holds half of our DNA (23 chromosomes). All of our other cells contain 46 Chromosomes. In the lab, they harvest an egg from which ever species they are cloning, and they remove the nucleus. They can then take the nucleus of a normal 46 chromosome cell and put it inside the egg- where it's nucleus used to be. The egg then "thinks" it is fertilized and will start to divide, and grow. This embryo is an exact replica of the parent cell. Cloning is a form of asexual reproduction, because sex was not involved in the creation of the new embryo. There are many ethical issues surrounding cloning. Some argue that scientists are "playing God" because they are creating new life. Some say that if a human were to be cloned- it would have no soul because it was not created by God. There are too many ethical issues to type here, but you get the idea. You'll have to decide for yourself where you stand. Hope this helps. good luck in school
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You knowledge of English appears to be even worse than your knowledge of science, which is depressing.\n\nLook, 'fitness' in evolutionary theory refers to fitness to reproduce. Those who are fit are those who can produce offspring, NOT those who evolve.\n\nSo of course all multicellular organisms eventually die. That is the whole point. Their offspring then inherit their niche. And because fitness is defined by the number of offspring produced the fittest organisms inherit the larger share.\n\nI hope this clears up a small part of your ignorance.
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There are two parts to this definition ... PhenotypeThis is the "outward, physical manifestation" of the organism. These are the physical parts, the sum of the atoms, molecules, macromolecules, cells, structures, metabolism, energy utilization, tissues, organs, reflexes and behaviors; anything that is part of the observable structure, function or behavior of a living organism.\n\nGenotypeThis is the "internally coded, inheritable information" carried by all living organisms. This stored information is used as a "blueprint" or set of instructions for building and maintaining a living creature. These instructions are found within almost all cells (the "internal" part), they are written in a coded language (the genetic code), they are copied at the time of cell division or reproduction and are passed from one generation to the next ("inheritable"). These instructions are intimately involved with all aspects of the life of a cell or an organism. They control everything from the formation of protein macromolecules, to the regulation of metabolism and synthesis.
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1. A DNA molecule refers to just a double stranded molecule but a chromosome is a condensed form of DNA complexed with proteins. An intermediate is the chromatin which is a network of fibrils consisting of DNA and they exist when the cell is not dividing.\n\n2. Prokaryotes have a single chromosme that contains only few proteins and appear as an electron-dense irregular shaped region called the nucleoid which is not enclosed by membrane. If you stretched this out, the chromosome would be a circular loop attached to the plasma membrane of the cell. Also, when they replicate, the replication occurs in two directions at once since the DNA molecule is cirular. Eukaryotes have much more proteins and when not being replicated are in the membrane bound nucleas as chromatin. Then the DNA replicates, it is dones by numerous origins of replication initially called replication bubbles that meet up to form replication forks. The broken segments of this replication method is calked Okazaki framents.\n\n3.Autosomal chromosomes are the rest of the chromosomes that are nonsex and are the same no matter what sex the person is. For example, there are 46 chromosomes in humans and one PAIR is your sex chromosome which determine your sex (girl = XX and boy = XY) while the other 44 are autosomal which you inherited no matter what your sex was.\n\n4. The word "complexity" is hard to define here because it is ambiguous and subjective. To us humans, a zebra may seem less complex since we cant tell them appart, but from the zebra's prospective, their unique stripe patterns differntiate very clearly who is who. At birth, the mother zebra spends 20 min. with its calf so it can memorize stripe patterns. However, understand the aim of the question, the answer is no. There is no proven evidence that shows a direct correlation of chromosome number to complexity. Well, you may think that since there are more chromosomes, these organisms have more alleles coded for them and are thus more complex. Not necessarily true. Some genes code for mutliple traits while others may have multiple genes for one trait. Also the vast number of genes that are coded in a single chromosome is very high. Ex. A Human has 46 chromosomes but a Crayfish has 200! Therefore more chromosomes do not mean higher "complexity" (at least in this implied definition)
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Species have NOT evolved to die.  The more accurate phrasing is that they have not evolved to live indefinately.  After reproduction, and the passing on of genetic material, Selection can no longer exert any pressure on a population.  This means that a species cannot evolve a longer life span unless there is some environmental pressure which causes reproduction to occur later, thereby selecting those individuals who can both survive, and remain fertile until such a time.  Actually, since reproduction is the defining event, some think that populations may actually enrich with genes which cause enhanced function in early life, but are detrimental later, eg. increased calcium deposition in bones.  Its called antagonistic pleiotropy.  \n\nRecent research on yeast has found genes which are regulated by metabolism, and can sense a dearth of nutrition.  When they do, they cause changes which allow the yeast to extend both their life and fertility until conditions improve.  So you can see that there are some ways in which selection can yield a longer life span.
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Genetic Mutations\n\nIn biology, mutations are changes to the genetic material (usually DNA or RNA). Mutations can be caused by copying errors in the genetic material during cell division and by exposure to radiation, chemicals, or viruses, or can occur deliberately under cellular control during the processes such as meiosis or hypermutation. In multicellular organisms, mutations can be subdivided into germline mutations, which can be passed on to progeny and somatic mutations, which cannot be transmitted to progeny. Mutations, when accidental, often lead to the malfunction or death of a cell and can cause cancer. Mutations are considered the driving force of evolution, where less favorable (or deleterious) mutations are removed from the gene pool by natural selection, while more favorable (beneficial or advantageous) ones tend to accumulate. Neutral mutations are defined as mutations whose effects do not influence the fitness of either the species or the individuals who make up the species. These can accumulate over time. Contrary to tales of science fiction, the overwhelming majority of mutations have no significant effect, since DNA repair is able to revert most changes before they become permanent mutations, and many organisms have mechanisms for eliminating otherwise permanently mutated somatic cells.
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26\n\nIn meiosis, the chromosome pairs are divided in half so the new cell has 1 of each.  This is because this is used to produce cells for reproduction.\n\nWhen 2 of these cells come together,they create 52 chromosomes again to create a new organism with half of each parents genetic material.
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I guess if you reasoned it out, the answer would be plain and simple:\n\nA cell couldn't be due to the fact that a gene is found inside a cell.\n\nA chromosome neither, due tot he fact that a gene is part of a chromosome.\n\nA trait first of all is not a genetic material, but the expression of the gene.\n\nAn obviously the only answer which remains is DNA.\n\nnucleotide + sugar + phosphate group ->  Nucleic acid -> make a DNA strand -> which make up a gene -> which is found in a chromosome -> which are found in the nucleus.
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We are constantly evolving. If you look at statistics over the last hundred years, people are getting taller. (Go into an old, old home - the stairs will be smaller - people were smaller.)\n\nEvery time that DNA replicates, there is a possibility for an error. These can be positive or negative, but it the error is transmitted to the next generation, it will make changes in person. These changes are EVOLUTION. \n\nUnfortunately, the survival of the fittest isn't accurate anymore, as people with defects are now living long enough to reproduce and making faulty copies of their DNA. \n\nWe will continue to change, slowly, but evolution is happening all around us, and in us, everyday.
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Though you will ignore the answer, I'll try anyway.  \n\nYour question, with explanation was a classic straw man, so I'll answer your question.\n\nI do not support ID as per se, but, all they are saying is the following:\n\nStep 1:  dna exists.\nStep 2:  later, new dna exists which could not have been eluciadated from existing dna, because there is unquestionably new and unique information in this new dna, which did not exist before.\nStep 3:  how did it happen?  \nStep 4:  it either happened by some still unknown natural or biological mechanism, or it was caused, created.\nStep 5: the natural or biological mechanism seems unlikely as the cause for strictly reasonable and logical reasons.  However, if it could be discovered, it would be one of the most important discoveries ever, and would be communicated as such.  This is still one of the mysteries in biology.  \nStep 6:  new information is not created by natural and random processes.  This just does not occur in nature.  Based on experience and logic.  \nStep 7:  based on the above, it seems that design is involved.\n\nThis is not hard logic.  The point is that you have closed your mind to the issues the ID people are trying to consider, and ID people are fully engaged in science.  What happens if you are wrong?\n\nBasically, ID does not say design is perfect, however, it could very well be optimal, and that takes intelligence, and then it is not a flaw.  ID people have answered your question many times.  Many you need to do some reading.  I cannot say the retina is shoddely wired.  Your remark was a rhetorical and opinionated remark.\n\nNot trying to give you a hard time.  Just the facts.\n\nEdit:  Anything that is proven by science, I agree with.  Duplication is well known.  I hope I was clear.  The issue is:  Here is dna without a certain new function, like a lung, or kidney, or brain, or eye, or skin, of bone, or hair, of tear duct, or immune response, etc.  Later, a 100 lines, or millions of lines of new dna exist with this code.  Duplication is not the mechanism, for the function did not exist, and requires some pretty profound new engineering to create.  The unanswered question is:  how did it happen?  Randomness cannot be part of the solution, since the improbabilities are far too great.  \n\nCan this question be answered, or is it still open?  The answer I usually get is, well just because we do not know, does not mean we should accept the possibility of a creator.  I say, you should consider both, until we have an answer.  You may lean one way or the other, but both are still possibilities.  \n\nThe most knowledgeable scientists agree for example, in cosmology, the closer we get to the beginning of the universe, the more the questions become philosophical and theological.  You are discounting a vital side of the story.
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Yes, because one of the characteristics of life is the ability to replicate, or reproduce, and they definitely do that.  Another is the ability to move freely and independently, and they also do that.  Check the website below for other information.
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DNA contains a complete blueprint for the body, not only for growth but also repair.  Although each cell contains a complete copy of the original DNA, the particular cell is differentiated from the original DNA containing cells at conception and can only make cells of a particular type (blood, skin, bones, brain, etc.).  During growth, cells divide because the blueprint has not been completed.  Much later little growth is required except perhaps hair, skin and gut lining, etc. and DNA splits and reproduces to make repairs (to patch wounds, etc.) to restore the blueprint construction to normal best it can.  Differentiation may occur because particular cells are influenced by surrounding cells.  Therefore a new toe never grows within a damaged eye.
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good way to remember - mitosis happens in my toes - asexual reproduction of cells, otherwise known as growth.\n\nMeiosis is the process by which sexual reproduction occurs, as in a combination of gametes (containing half the necessary genetic material) to create a new cell.\n\nAlleles are portions of genetic material that have a physical (or phenotypic) effect. These are usually sections of chromosomes, bundles of colied and intertwined DNA.\n\nMutation is any alteration of the Deoxyribonucleic acid (DNA) or Ribonucleic acid (RNA). Evolution could not occur without mutation. Intelligent Design is a bunch of nonsense. It's all random and we are very lucky to be alive and sentient. Don't waste your intelligence on Yahoo Answers. I will now follow my own advice...
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You would end up with the already existing DNA being split in some way. This means that neither of the two daughter cells would have all of the genetic material they need.
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I'm supposing that you are referring to the idea that acquired knowledge is stored in neurons, which would seem to indicate that the knowledge was coded into DNA.  IFF this were true, then there is no reason why that DNA would be present in gametel cells, those used to pass on genetic information through childbirth.  Again IFF both of these did occur somehow, you would still only recieve half of that information from each parent.  So, you might have knowledge of how to steer or how to set a sail, but you wouldn't have the knowledge of the in-between actions.  Finally, let's imagine that these all happened to work out fine, your ancestors stored their knowledge in DNA, that DNA was present in gametal cells, and you inherited a full set of the information; the problem is that the information on a DNA strand is accessed sequentially.  The body does not access the DNA code for creating gametal cells until a person is about 12.  It also doesn't use the code for rapid growth until the same time period.  So, in all likelihood, IFF the three preceding requirements were met, you still wouldn't access the information until it was time, perhaps when you begin studying how sail.