what is the chromosome theory for inharitance?
921853
The theory that chromosomes are linear sequences of genes. The unifying theory stating that inheritance patterns may be generally explained by assuming that genes are located in specific sites on chromosomes.
653912
Realistically, none, because the chromosomes will cross over during meiosis, so none of the chromsomes will be exactly as they descended from the parents.\n\nBut if the haploid number is 6, and you pretend there's no crossing over, then there are 2^6 ways for the chromosomes to assort, and 2 of them will be 6 chromosomes from a single parent.  So that's 1 in 32, or about 3%.
54152
Biostat girl is correct.  In the formation of gametes, the chromosomes are independently assorted, and that's after homologous recobination, where maternal genes and paternal genes aon homologous chromosomes get shifted back and forth to make completely random new chromosomes that have genes from either parent.  So the probability of complete similarity in that situation is the same as that for siblings: theoretically possible but with a statistical probability of essentially zero.
742169
one chromosome comes from each parent
654620
Simply put, we say that chromosomes are the basis of inheritance because they contain all the DNA coding which tells our cells how to replicate, and tells our body as a whole which tissues and organs to produce, where to put them, etc.  Also, we refer to chromosomes as the basis of inheritance because all our genes and DNA are contained within chromosomes, and so we don't inherit any of those separately from inheriting the chromosomes they are found upon.\n\nThere are a few reasons we know the DNA in our cells is primarily responsible for our inherited traits (in other words, the traits which not only make us human, but which make us human beings with traits unique to our parents, such as having "our mother's eyes", or "our father's nose"), is because when DNA is removed from cellular structure, the affected cell cannot replicate or divide successfully, and when DNA is altered, the alterations we see in the DNA are expressed in the body of the creature whose DNA was altered.\n\nAs a result of consistently seeing that cells deprived of their DNA cannot replicate themselves or manufacture new structures, while cells deprived of other parts can still do so, and can construct new parts to replace what they lose as they are damaged, we are sure DNA is the material responsible for the process of replication of cells.\n\nWe are also sure it is responsible for inheritance and growth because we can watch the DNA of growing organisms consistently express different parts of itself to influence how the organism in question grows, thereby giving us answers to not only whether or not DNA is the responsible structure for such things, but also just which parts of DNA (known as genes) are responsible for which areas of development.\n\nFinally, we say it is the source of inheritance because it is directly passed from parents to offspring no matter how reproduction is accomplished, and is responsible for determining how the offspring develops.  For creatures which reproduce asexually, it means their DNA is transferred directly and virtually unchanged, producing offspring almost identical to the parent.\n\nFor creatures which reproduce sexually, the body of those ready to reproduce manufactures a special type of cell (known as a gamete), using a different process of DNA replication which results not in two cells with DNA identical to the first cell, but four cells with "half versions" of the DNA specifically made to compliment the incomplete version of the DNA of our chosen mate.  When these two DNA codes combine, they determine the blueprint upon which our offspring will develop, meaning the physical characteristics our children end up with is what we have directly passed on to them... or in other words what they have inherited from us as parents.\n\nThe evidence of this is found not only in the physical similarity of children to their parents, but in physical defects which are expressed through their genes (such as fanconi anemia or cystic fibrosis), where the expressed genetic flaw can be traced back to "carrier genes" in the parents-- or in other words single flawed genes being suppressed in the parent's DNA by a healthy copy of the gene which was not inherited by the offspring, thus resulting in its illness, and we can also trace the unique genetic patterns of offspring back to their parents, usually with such certainty because genes are so complex and unique to each organism, there is no possibility of the genetic structure of the offspring in question having come from any other source than its parents... thus assuring us that not only does the offspring's DNA determine the parameters of its physical development, but also that the DNA in question was inherited exclusively from the parents.\n\nIf you are wondering why we translate such things into notions such as legal inheritance, it is because we're one of many organisms which has evolved to naturally favor its own offspring a
166727
This may seem like a silly suggestion, but try representing the elements mentioned in your textbook (which I'm sure has some illustrations) with pieces of paper, matches, beans or something like that, so you can understand the events and the outcome. \nNow, if you _really_ want an explanation, here it comes (I've ommited the names of the phases, they'll be in your textbook).\n\nMeiosis includes 2 cell divisions with different characteristics. \nWe start with a diploid (2 n) cell, in which DNA duplication has occurred so that each DNA strand is double. These strands do not yet appear as chromosomes (condensed bodies); in fact, the chromatin strands have to be "relaxed" in order to duplicate. \n\n***Meiosis I: (in which the nº of chromosomes decreases to half)\n1. The chromatin (DNA strands) starts to condense and appears as small dense dots (the chromosomes) within the cell nucleus. These chromosomes will each have 2 "arms" (they look like an X or a V) because the DNA in each has been duplicated.\n2. Now all these chromosomes align in homologous pairs, with the aid of a transparent structure formed by tiny intracellular fibers (the spindle) that has formed and will help them to move in orderly fashion within the nucleus.\n3. While they keep condensing, each homologous chromosome contacts its "brother", and they exchange some fragments of their DNA ("crossing over"). Usually only one "arm" of each  chromosome participates in crossing over. \n4. In the meantime, the nuclear membrane is disintegrating...\n5. The pairs of homologues, still united, align at the middle (equator) of the spindle... \n6... and then each pair of homologues is divided, one chromosome of each pair goes toward each "pole" of the spindle. \n7. New nuclear membranes form around the 2 groups of chromosomes. Each of these groups will only have ONE of each pair of homologues. Essentially the information in each new nucleus is the same, BUT has some differences because, as you recall, there has been crossing over i.e. partial exchange of DNA between homologues. \n8. The original cell with the 2 nuclei divides and forms 2 cells, with half the nº of chromosomes of the original cell (haploid or n). Each of the chromosomes still has a duplicate DNA strand.\n\n... the cell takes a short break (you can take a break too!)... but the chromatin does not duplicate this time (it's already done that)\n\n***Meiosis II: (in which each double DNA strand becomes single again, this phase is similar to a normal mitosis).\n1. The chromatin condenses again, so that it appears as chromosomes.\n2. This time the spindle aligns the center of each chromosome at its equator.\n3. The central part of the chromosome is duplicated and the sister "arms" (chromatids) separate, each migrating to opposite poles.\n4. Now you have two groups of chromosomes, each group still has the haploid (n) nº of chromosomes (the same amount with which they started this 2nd meiosis) but now, each chromosome has a single DNA strand. \nA new nuclear membrane forms around each of these groups of chromosomes.\n5. The rest of the cell divides.\n\nSo, to sum up: you started with ONE diploid cell. You end with FOUR haploid cells. In animals, this process only happens during the production of gametes. \nIf we're talking about the formation of female gametes, then only ONE of the 4 resulting cells will become an ovule (and that only after more maturation), the other 3 cells form "polar bodies".\nIn contrast, when it's spermatozoids being produced, all FOUR resulting cells will become spermatozoids. \nThat's one of the reasons sperm is cheaper than ovules! There's just more of them in the entire animal kingdom.\n\nNow, what is the purpose of this extremely complicated (the above is a very simplified version) process? The result will be cells that have half the chromosomes of the normal body cells. These cells
278700
A chromosome is a threadlike stand of DNA which controls your hereditary information (hair color, etc)
301931
umm, though i'm not sure what the question really says- i think you are asking about genetic diseases involved with chromosome number, if i'm right the following stands, if not then ignore it. \nif you have less or more chromosomes than 46 you will not survive far past fertilization, at least thats what i understand- either that, or you would be a different species- unable to produce a fertile offspring with a human.\n\nHowever there is a lot of confusion around Down's syndrome. This is caused by non-disjunction of chromosomes during meiosis, and creates trisomy genotypes on chromosome 21. \n\nTrisomy and non-disjunction can also occur on chromosome 17- causing another disease, which i have momentarily forgotten the name of. sorry.
268018
Inside of each cell of the human body is a nucleus.  Inside of it are genes and chromosomes.  Inside of those are complex strands of proteins and amino acids that together are calle deoxyribonucleic acid or DNA.  This DNA contains the "blueprint" for an entire human being.  When two people mate, their DNA gets combined to form a new human, unique but having many characteristics shared by the parents' DNA.  Have you ever heard the term "genetic lottery"?  This is because each time the DNA from two humans is combined to make a third new human, the combination of DNA is to an extent random.  Only to an extent.  I inherited my mother's bad vision and my father's bad teeth.  I inherited my father's nose.  But I am taller than either of my parents.  My hair is a completely different color than either of theirs.  Sometimes DNA, genes, and chromosomes are imperfectly formed.  Each gene controls certain characteristics about a human being.  Completely normal parents can wind up having a baby with Downs' Syndrome (Mongolism, a type of mental and physical retardation).  Completely normal parents can wind up having a dwarf baby.  But other problems are passed down directly from one generation to the next.  Hemophilia is one example, the people whose blood won't clot.  They can bleed to death from a cut.  If they fall they can bleed internally until they die.  Hemophilia is passed down from one generations to the next in the female line.  Queen Victoria, who was related to most of the people of the royal and imperial houses of pre-World War One Europe, was a carrier of the genetic defect of hemophilia.  The women who carry this are usually immune to it.  It is the boys they give birth to that can suffer and die from uninterrupted bleeding due to this genetic defect.  How to prevent one's son from being hemophiliac if one is a female carrier?  Adopt.
698789
it is NOT in mitosis!!!!\nmitosis happens AFTER G2\ncytokinesis is on of the final stages of mitosis!\n\neverything else is right :)
128668
Karyotype\n\n(FISH (Fluorescent In Situ Hybridization) can also be used if visualization of certain regions on specific chromosomes is desired.)
910316
chromosomes are what makes you they carry your genetic information eg hair colour eye colour, you have 46 chromosomes in each cell or 23 pairs, but in sex cells the egg and the sperm u have only 23 as they join up with the opposite sex cell to make 46. thats meitosis, miosis is the development of ordinary body cells, this is done so if for example you cut your self you body is able to repair itself, hope you understand this and it was useful for you :)
268425
Mendel's law of independent assortment basically says that each chromosome pair will separate during meiosis individually, regardless of whether the chromosome originated maternally or paternally.  So for example, if there are two pairs of chromosomes, 1 and 2, and each have a maternal and paternal copy (1M, 1P, 2M, and 2P), pairs 1 and 2 will segregate without input from the other pair.  So during meiosis, when the a haploid cell is formed with only one chromosome copy, there are many different combinations that can be formed.  The cell could contain 1M/2M, 1M/2P, 1P/2M, or 1P/2P.  It is easy to see how organisms with more chromosome pairs (humans have 23 pairs, 46 total) will produce more combinations, hence diversity among the species.  Hope that helps!
870300
Measuring chromosomes as a whole isn't a very good way of determining relationships between species. Although humans have 46 chromosomes (23 pairs) versus chimps' 48 (24 pairs), it's clear from looking at the structure of the chromosomes themselves that one of the human ones is composed of two of the chimps ones that have joined together. We can even see the end markers of the chimps genes in the middle of our joined one.\n\nIn terms of overall genetic difference between humans and chimps, it depends on exactly how you measure it but it's between 1 and 4 per cent. \n\nUnfortunately the answers given earlier about pigs being closer aren't accurate. They share large-scale physiological similarities, which is why heart ops may be possible, but this has nothing to do with DNA.\n\nA good reference for all this stuff is the Talk Origins archive at http://www.talkorigins.org
118008
No. B'coz if a perosn is heterozygous for a trait, the person will express the dominant trait. And, so will a person homozygous (dominant allele) for that trait. Therefore, it's not possible to differentiate between the two unless one obtains their karyotype chart.
699918
Humans have 46 chromosomes, not 26. \n\n23 come from mom, 23 from dad.
295926
I think one is the division of chromosomes and that is just a guess as for the other I assume that it has something to do with two sexes becoming one.