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quote:Originally posted by arielsorry if it was ambiguous,i was just going by the short definition in the glossarywellthe word was:progymnosperm
quote:a.k.a Dinosaur's Dinner
quote:Originally posted by ariel"put your left hand on the asdf keys put your right hand on the jkl; keys"hahah that was the first thing i ever learned about typing i took a test a while ago and i got 60 words per minute i think!
quote:Condition in which one allele of a pair is not fully dominant; a heterozygous phenotype somewhere between both homozygous phenotypes emerges.
quote:Originally posted by Ray hintonits called she was sleeping with the milkmanhow the devil did you get thisquote:Condition in which one allele of a pair is not fully dominant; a heterozygous phenotype somewhere between both homozygous phenotypes emerges.from thisi didnt even get the question [xx(]measure twice,cut once.
quote:Codominance/ Incomplete DominanceIn certain cases, a "blend" of genes will occur because neither of the two genes of a genotype are dominant over the other. As an example, in blood cells, the trait for blood type has three different alleles: type A, type B, or type i, with i being recessive. If a father passes a gamete with the allele of type A and the mother passes on type B, then codominance results, with the offspring being type AB since neither allele type dominates the other.Incomplete dominance occurs when certain of the recessive gene appears within the phenotype of the organism, causing a blend in between both the dominant and recessive gene.
quote:n genetics, dominance relationships control whether an offspring will inherit a characteristic from the father, the mother, or some blend of both. More technically, they control the ways genes interact to express themselves as phenotypes in a diploid or polyploid individual.There are three kinds of dominance relationships:Simple dominance Incomplete dominance Co-dominance Incomplete dominanceIn incomplete dominance, a heterozygous genotype creates an intermediate phenotype. In this case, both the dominant and recessive gene are expressed, creating a blended or combined phenotype. A cross of two intermediate phenotypes can result in the reappearance of either the parent phenotypes or the blended phenotypes.The classic example of this is the colours of carnations.---- R --- rR -- RR -- rRr -- Rr --- rrR is the gene for red pigment. r is the gene for no pigment.Thus, RR offspring make a lot of red pigment and appear red. rr offspring make no red pigment and appear white. Rr and rR offspring make a little bit of red pigment and therefore appear pink.An example of incomplete dominance in humans is mordan, a trait that is exhibited when eye color alleles from the maternal and paternal chromosomes are blended. This usually occurs when one parent has green eyes and the other parent has brown eyes–the child will have dark blue eyes.Co-dominanceIn co-dominance, neither phenotype is dominant. Instead, the individual expresses BOTH phenotypes. The most important example is in Landsteiner blood types. The gene for blood types has three alleles: A, B, and i. i causes O type and is recessive to both A and B. When a person has both A and B, they have type AB blood.Another example involves cattle. If a homozygous bull and homozygous cow mate (one being red and the other white), then the calves produced will be roan-colored, with a mix of red and white hairs.Example Punnett square for a father with A and i, and a mother with B and i:---- A --- iB -- AB - Bi –- A --- OAmongst the very few co-dominant genetic diseases in humans, one relatively common one is A1AD, in which the genotypes Pi00, PiZ0, PiZZ, and PiSZ all have their more-or-less characteristic clinical representations.
quote:Originally posted by Ray hintonisnt the english language great,it is my mother tongue,but i understand and speak more french,german,danish,spanish,and nearly as much serbo-croat,if this page is anything to go by,i wish i had paid more attention at school,act in haste,repent at leisure,as some one once said.measure twice,cut once.
quote:sorry for these amiguous words
quote:Originally posted by another_someoneThe word that seems closest is senescence. To me, it seems more the study of ageing, although arguably ageing is the process of natural death.George
quote:I can't believe you had to use Wiki to come up with codominance. I thought everyone knew that.