Are dominant characteristics always more frequent in a population than recessive characteristics?  y or y not?
918396
No, it depends on which form of the gene (dom or rec) is more advantageous.  For example, having 10 fingers and 10 toes is recessive.  12 fingers and 12 toes is dominant but you see it rarely.  Just because something is dominant doesn't mean it will show up more often, it's just more easily expressed.
694770
sure, the parents probably have two recessive traits, green and blue eyes, and for the child the dominant trait showed up, brown eyes\nin a simple way, a baby gets one of two variations of a gene from each parent\ndominant trait is dominant because when it is paired with a recessive, it shows up instead of the recessive one. recessive traits only show up when the baby gets the same two recessive traits from the parents\nall other choices will make the baby get brown eyes\nin this case my teacher said that brown eyes is a dominant trait
374887
Very simply put, dominance and recessiveness are characteristics of genes.\n\nA dominant gene is expressed (shows up visibly in the offspring) when only one copy of the gene is present, on one chromosome from one parent. Let's say Tallness is a Dominant gene. If you have ONE tall parent, and get ONE copy of the Tall gene, you will probably be tall. If your tall parent was the son or daughter of a TALL and a SHORT person, they may only have ONE copy of that gene. If you get both SHORT chromosomes from Mom and DAD, you will NOT be tall. So you have 50 to 100 chance of being tall with a Dominant gene.\n\nNow, let's take the gene for BLUE eyes. It is recessive. You need TWO copies of this gene to get blue eyes. If Mom has blue eyes and Dad has blue eyes, and you get copies of both blue eye genes, you will have blue eyes. But if Mom has blue eyes, and Dad has brown eyes, you might end up with Brown eyes. Don't that make your blue eyes brown, so to speak.\n\nBUT..if Dad's mom had blue eyes and Dad's dad brown (your grandparents) and if Dad has one blue eye gene and one brown eye gene and has brown eyes AND if your Mom still has those blue peepers, you have a 1/4 chance of ending up with one blue eyed gene from AND a blue eyed gene from Dad and you will also have blue eyes like your Mum. Don't that make your brown eyes...blue?
119148
A recessive trait can be passed on in a family lineage infinitely and not present itself until two people who have that recessive gene mate and produce a child who gets both the recessive gene from both parents.
841943
Mendel's laws predict that a monohybrid cross between any two heterozygotes would produce offspring in a 3:1 phenotypic ratio.  That is:\nAa  X  Aa = \n1 AA - Dominant Phenotype\n2 Aa - Dominant Phenotype\n1 aa - Recessive Phenotype\n\nSo, 3 Dominant : 1 Recessive\n\nNow for your two instances:\n\nA.\nIn the case of codominance we have two different dominant alleles and one recessive allele.  When both dominant alleles are present, the phenotype is different from that seen when either of the alleles is present alone (homozygous or heterozygous).  A classic example of codominance is that of blood types.  Type A and type B are both dominant phenotypes, type O is the recessive phenotype, and type AB is the codominant phenotype.\n\nBack to your question, lets say:\nA = dominant allele 1\nA* = dominant allele 2\na = recessive allele\n\nCrossing two heterozygotes: Aa X A*a results in\n1 AA* - codominant phenotype\n1 Aa - dominant allele 1 phenotype\n1 A*a - dominant allele 2 phenotype\n1 aa - recessive phenotype\n\nSo we have a 1:1:1:1 phenotype ratio, not Mendelian expected 3:1\n\nB.\nRecessive lethal alleles are a situation where the homozygous recessive genotype is lethal to the organism.  So if we cross two heterozygotes:\n\nAa X Aa \n\nWe get:\n\n1 AA - dominant phenotype\n2 Aa - dominant phenotype\n1 aa - lethal, so this offspring is never seen\n\nSo here all the offspring seen are of the dominant phenotype, again defying Mendel's predicted 3:1 ratio.\n\nHope this helps!
363834
John is actually incorrect... our characteristics are not governed solely on out genes, there are many factors that are involved.\n\nSome characteristics such as hair colour and eye colour are govered by our genes, but we can actually appear differently depending on how we developed in the foetal stage of development, as well as injuries we may sustain, what we eat, how we live, and psycological responses that lead to hormonal responses (or vice versa). All of these can change markedly our characteristics.\n\nSome simple examples include 'wide feet', spinal malformation (eg. muscular scoliosis), asthma, and many more. Note that these may be influenced by genetics, but having the gene does not mean you get the characteristic.\n\nConsider that two identical twins can actually be told apart becasue one is often slightly taller, or slightly fatter or has different characteristics, however their genes are the same.\n\nConsidering that the environment in the womb during pregnancy can change a human's characteristics quite markedly as it can also change hormonal development, then we must realise that if you were to be cloned then your clone may look very different from you... although you will most likely look similar enough to look like siblings.
241092
It is both.\n\nIn my biology and psych classes, my profs often remind us that nothing is as simple as one or the other. Yes, there are genetic factors and yes, there are environmental factors. Both influence how you turn out.\n\nIn family studies of schizophrenia (oh spelling error), if an aunt or uncle had it, a child had a 30% chance of developing it. If the child's sibling developed it, the child had a 50% chance that they would develop it as well. However, if the child's identical twin had developed it, the child had a 74% chance of developing it. If you remember from biology....aunts and uncles are less genetically close as siblings are...and siblings are less genetically close as identical twins (since id twins have the exact genetic make up). But...if the condition were entirely genetics, if one identical twin has it, the other one would have to have it as well. Identical twins who were seperated...if one had it, the other had a 50-60% chance of developing it, which shows that environment definately plays a role.\n\nThe same goes for most other traits.
898195
the result of fl is barr(if it is dominant) or else white.one main ground rule of inheritance is that it may be white or barr but one can be dominant only for 2 generations it's not the matter but in  the third gen.the recessive will take the turn
851796
In search type in:\nis lupus a dominant or recessive trait.
515090
dominant e.g. Aa, AA - Recessive -aa
807540
First thing you want to check is to see if the trait skips a generation or not.\n\nIf it does then chances are that it's a recessive trait.  If it doesn't then chances are that it's a dominant trait.  \n\nI want to stress the word "chances are" because it's possible that a trait NOT skip a generation yet still be a recessive trait.  Blood O type, for example, is recessive whereas A and B are dominant.  If both parents are blood type O, the child will be blood type O as well.  \n\nNext thing you want to check out is count the number of traits in the males compared to females.  \nIf it's about a 50:50 ratio, then it's an autosomal trait.  \nIf it's mostly males and virtually no females, then it's an X-linked recessive.  \nIf it's about 1/3 male and about 2/3 females, then it's X-linked dominant (doesn't happen very much but still possible)\n\nGood luck!  Hope this helps!
974731
For each trait (or each contributor to a trait, but I'll keep it simple here), each person has two genes.  Also, for each trait, there is a dominant and recessive allele.  In order to have the dominant version of the trait, one only need have one of the dominant alleles.  In order to have the recessive trait, you have to have received the recessive gene from both of your parents.\n\nFor example, let's say that both of your parents have a dominant trait (say, having five fingers), but both are carriers of the recessive gene (six fingers).  I'll use F to denote the five-finger gene and s to denote the six-.  Here are the possibilities for their children:\n\nDad:  Fs\nMom:  Fs\n\nThere are four possibilities:  FF (five), Fs (five), sF (five), and ss (six).  So, on average, 25% of this couple's children would have five fingers and no chance of passing hyperdigitosis to their children; 50% would have five fingers but carry the gene for having six; and 25% of their kids would be able to give their friends "high-sixes."  The kids with six fingers would be guaranteed to pass that gene on to their children, but their children would only end up with the extra digit if their mother also passed that gene to them.
222852
a dominant genetic disorder only requires one copy of the causitive gene, so if one of your parents had one copy of the gene and the other none, you would have a 50% chance of getting it. if its recessive, it takes two copies of the gene to actually have the disease, so both parents would both have to have a causitive gene. so dominant usually affects every generation, while recessives usually skip and are less frequently manifested. thats if its autosomal (meaning not on a sex chromosome). if its X-linked, then it gets more complicated. see the link below (pages 4-9) for more help and examples of diseases.
639406
When Mendel began to scientifically analyze "heredity", he concluded that each parent (mother + father) donates an "allele" for a characteristic (trait) in question.\n\nA lettering system was used: Capital letters indicated that the allele is DOMINANT; lower-case letters indicate that the allele is RECESSIVE.  This is the case for 22 of the 23 chromosome pairs in humans.  The 23rd pair are called the sex chromosomes.  Females (mother) always donate an "X" allele; fathers can donate either an "X" or a "Y" allele.\n\nIf a person's genotype for their sex is "XX", this means two things.  1: Both X's are the same (in other words, X and X are identical).  Identical alleles are called HOMOZYGOUS.  2: A human who is "XX" is female.\n\nA human who is "XY" is male.  "X" allele and "Y" allele are DIFFERENT.  Thus, they called HETEROZYGOUS.  We refer to men as being "heterozygous" in that a male's SEX alleles, 'X' and 'Y' are different.\n\nLet us say "B" is the dominant allele for brown eyes, and "b" is the recessive allele that can result in blue eyes.  A person who is "Bb" is heterozygous (B is a different allele than b).  A person's who genotype is Bb is likely to have brown eyes.  A person who is "BB" is HOMOZYGOUS (1st B is identical to the 2nd B) and will definitely have brown eyes.  A person who is "bb" is HOMOZYGOUS (1st allele 'b' is identical to the 2nd allele, 'b') for the recessive allele; this person will have blue eyes.
699803
There are two type of alleles: dominant and recessive.\n\nThe rule of dominance is basically that if dominant is present in the allele, the phenotype (appearance) will not show the recessive gene.\n\nIn Mendel's pea plant experiment, his dominant was purple flower  (PP) and recessive was white flower (pp). \nWhen he crossed purple with white, he got all purples, with genotype (gene) of Pp. Since purple is dominant and is present in genotype, the flower is purple.
692190
Only if a genetically recessive trait runs in the family and both the guy and his sister have the defective chromosome, only then does the baby risk having a birth defect or mental retardation - even then(ie, with the defective recessive chromosome in both), the chance would be 1 abnormal child out of 4. If the guy and the sister have no such defective chromosomes, then the question of an abnormal/retarded child does not arise.\n\nIf, however, a genetically dominant trait runs in the family and either the guy or his sister have the defective chromosome, then the risk increases to 1 in 2  and if both have it, then the risk is 3 out of 4.\n\nIn any case, whether the baby will be normal or abnormal cannot be determined until a karyotyping of both the guy and his sis is done. Having said that, the rate of such disorders is quite low and in all probability, the child will be normal.
958482
The dominate gene, or trait is stronger than the recessive.\n\nSay your dad has brown eyes. Your mon has green.  (brown is the dominate gene)  You would have more brown in your eyes cause the brown gene is dominate (stronger)\n\nWill