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What else can I help you with?
Where are the effects o f a dominant allele seen?
it is present (shown) whenever it is present ( see Punnett Square) it will overthrow a recessive allele as long as it is there. it's effect is that you will get a certain trait for that allele. A Punnett Squar will help you the most.
What effect does natural selection have on the frequency of a recessive lethal allele?
Perhaps not much as the recessive allele is masked in heterozygous condition. Depends on penetration and expresivity of the lethal allele, but any homozygous expression is fatal, so one can expect negative frequency selection; the freqiency is kept low by selection.
What is dominant and recessive allele?
A dominant allele is an allele where its phenotype will always be represented when the allele for that gene is present. A recessive allele can be masked by a dominant allele when a dominant and recessive allele are present for the same gene. A recessive allele will only present itself when two recessive alleles for a trait are present.
What is the phenotype of a homozygous dominant person?
Homozygous dominant- means having dominant alleles at the same locus on a chromosome.More correctly, it's the same locus on two chromosomes (a homologous pair).
What could cause a mutant fly embryo to develop two tail ends but no head?
This is called bicoid mutant phenotype, and is caused by a maternal effect gene which is a gene that, when mutant in the mother, results in a mutant phenotype of the offspring regardless of the offspring's genotype.
When the dominant allele does not completely mask the effect of the recessive allele in the heterozygote it is called polygenic dominance incomplete dominance dominance corecessive codominance?
When the dominant allele does not completely mask the effect of the recessive allele in the heterozygote, it is called incomplete dominance. In this case, both alleles contribute to the phenotype, resulting in an intermediate phenotype.
What gene produces an effect only in the homozygous state?
Recessive genes typically produce effects only when an individual is homozygous for them, meaning they have two copies of the recessive allele. If an individual is heterozygous for a recessive gene, the dominant allele will often mask the effects of the recessive allele.
What is contributing allele?
A contributing allele is a genetic variant that is associated with a particular trait or disease. These alleles can have a small to moderate effect on the trait, increasing or decreasing the likelihood of developing that trait. Multiple contributing alleles can interact to determine the overall phenotype of an individual.
What is meant by complete dominance?
DefinitionnounA kind of dominance wherein the dominant allele completely masks the effect of the recessive allele in heterozygous condition.SupplementFor instance, an individual carrying two alleles that are both dominant(e.g. AA), the trait that they represent will be expressed. But if the individual carries two alleles in a manner that one is dominantand the other one is recessive, (e.g. Aa), the dominant allele will be expressed while the recessive allele will be suppressed. Hence, theheterozygote (Aa) will have the same phenotypeas that of the dominant homozygote (AA). This condition is called complete dominance.
Two dominant alleles are expressed at the same time?
The alleles are not always both expressed.Take the simplest example, a case when there are only two alleles for a trait, R and r. When the organism is a heterozygote, meaning that it has both alleles with a genotype of Rr, only the phenotype carried by the dominant allele, the R, will be expressed. The dominant allele masks the phenotype of the recessive allele. A case in which only the dominant phenotype is expressed in a heterozygote is a case of complete dominance.*Cases where the dominant allele does not completely mask the recessive allele are cases of incomplete dominance and co-dominance.In incomplete dominance, the dominant allele has some effect on the recessive allele, but not a full effect. This results in a third phenotype in the population. Think red and white flowers leading to pink flowers.In co-dominance, the dominant allele has as much effect on the phenotype of the organism as the recessive allele. Think red and white flowers now leading to red and white streaked flowers.
How do dominant and recessive alleles affect an offsprings phenotype?
The traits inherited depends upon the alleles that have been passed on from the father and mother.The traits that are exhibited is called as the phenotype. Dominant allele needs only one copy to be expressed.For example in a pea plant "T" represents the tall dominant allele and "t" the short recessive allele .TT - when there are two dominant alleles the pea plant will express the tall trait. The pea plant is tall.Tt - when there is one dominant and one recessive allele the pea plant will still express the tall trait.In this case the dominant allele masks the recessive allele and the pea plant is still tall.tt - when there are two recessive alleles the pea plant will express the recessive trait and the pea plant is short.For a recessive trait to show up there should be a pair of recessive alleles.
Is homologous dominant?
In genetics, alleles can be classified as either dominant or recessive. The term "homologous" refers to the pairing of chromosomes in meiosis. Whether an allele is dominant or recessive depends on its effect on the phenotype when paired with another allele. Homologous chromosomes do not determine the dominance of an allele.
How does the homozygous gene affect horse color?
If a horse is homozygous dominant EE, he is black. Homozygous recessive ee, he is red. A black EE horse that is homozygous dominant for the Agouti gene (AA) will be a bay horse. If that same EE black were homozygous recessive for aa, then he would still appear all black. The Agouti gene does not effect a red ee horse's phenotype.
Where are the effects o f a dominant allele seen?
it is present (shown) whenever it is present ( see Punnett Square) it will overthrow a recessive allele as long as it is there. it's effect is that you will get a certain trait for that allele. A Punnett Squar will help you the most.
These alleles show their effect on the phenotype whenever they are present in the genotype?
Dominant alleles carry traits or characteristics that will show no matter what. Recessive alleles carry traits where you must be homozygous for the recessive trait in order for it to show. Dominant alleles are represented by capital letters (EX: R or M) Recessive alleles are represented by lower case letters (EX: r or m) In order for a dominant allele to show, you can have either RR or Rr, since it is dominant. However, in order for a recessive allele to show, you MUST have rr. Hope this helps!
Does a dominant allele mask a ressessive allele?
In diploid organisms (those with two copies of each gene carried on separate chromosomes), one of the copies of a given gene may differ from the other copy of the same gene on the twin chromosome. In some cases one version of the gene (the dominant allele) has the effect of 'masking' the activity of the other (the recessive allele); that is, the presence of the dominant allele negates the effect of the recessive allele on the organism's phenotype. There are many mechanisms which can cause this phenomena, and it depends on the particular genes involved, but a simple model is one where the recessive allele is a biochemically inactive version of the dominant allele. In this case the dominant allele would mask the effect of the recessive allele by providing an active version of the gene. The dominant phenotype would be the one which shows the downstream effects of this activity, and the recessive phenotype one which shows the downstream effects of a lack of activity. The dominant allele is said to 'mask' the recessive allele because only one copy is required to result in an elimination of the recessive phenotype, whereas all copies of the gene must be the recessive allele to result in the recessive phenotype.
What effect does natural selection have on the frequency of a recessive lethal allele?
Perhaps not much as the recessive allele is masked in heterozygous condition. Depends on penetration and expresivity of the lethal allele, but any homozygous expression is fatal, so one can expect negative frequency selection; the freqiency is kept low by selection.
