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What else can I help you with?
How does a recessive trait show up as a visible trait?
Recessive alleles are only expressed in the phenotype if the organism is homozygous for the recessive allele (assuming diploidy). If the trait is sex-linked, then it will always show up in males if passed.
Why do fatal genes have to be recessive?
Because if they are dominant, then even one copy present in the organism would mean that the organism will be killed by the generic error (because they are fatal). Thus to be passed on they have to be recessive - in other words if an individual has a good copy and a bad copy (genes are paired - one from the mother and one from the father) the good copy must be dominant for the individual to survive.
What circumstances that genetic drift occur?
Genetic drift is the fluctuation of allele frequencies in a population due to chance. Chance plays a role in several ways. Copies of alleles can be lost because they never make it into gametes. Another possibility is, if the allele copy makes into a sperm, that sperm isn't the one that fertilizes an egg. Maybe the organism that carries copies of the allele in its gametes fails to find a mate, or is killed before reproducing. These kinds of events can influence the frequency of that alelle in a population, and occurs regardless of any selection for or against that allele. Obviously, the smaller the population, the larger the effect drift has on the allele frequency. For example, consider a population of four organisms. Each has two copies of a particular gene (one on each chromosome). Now, consider a mutation that creates a new allele for that gene, and that it appears on one chromosome of one individual. That allele will have a frequency of 1/8 in that population, so if it is lost, the frequency change will be 1/8. Now imagine a population of eight individuals; the frequency of the new allele would be 1/16, so if it was lost, the change in frequency would be less than in a population of four. It should therefore be easy to see that the effect of genetic drift on allelic frequency change is dramatically less in very large populations. In fact, in an essentially infinite population, genetic drift would have a negligible effect on the frequency of an allele. Another factor that can influence allele frequency, and which is a part of genetic drift is non-random mating. If an organism does not have an equal probability of mating with any other organism in a population, then some alleles will increase or decrease in frequency simply due to that. For instance, if a population exists over a large geographic range, individuals that live closer to each other have a greater probability of mating than those who live far apart. Species who employ reproductive strategies such as leks,where males gather together and compete for the privilege of mating with females are also examples of non-random mating. Lekking increases the effects of drift because it reduces what biologists call the effective population size, or the number of breeding adults. For the above reasons, when population geneticists want to study factors that affect the frequency of an allele (such as natural selection), and they want to minimize the effects of drift, they model populations that are very large (essentially infinite) and assume random mating.
Can an organism be heterozygous recessive for a trait?
Heterozygosity implies possessing both a dominant and a recessive allele and the phenotype that is exhibited in a heterozygote is always the dominant one (hence the name 'dominant'). Therefore, if a phenotype is associated with heterozygosity, it is automatically the dominant phenotype.
What is paper presentation?
Paper Presentation is all about how you put your topic or present your topic in front of the public. They see the way you present it. They way you put your points.Your way and the style of presenting the paper. The language you present the topic in. Like if you have to present the paper on "Nanotechnology"Here first thing is that you have collect the information from the source you would like to. It can be the internet or some books on the topic. You have to first arrange the information in the form as1. define the topic2. topic details2. current affairs3. advantages and the dis-adv.4. cuases remedies5. applications Then you have to prepare the "Abstract".Abstract- It is the details in short i.e not exceeding more than two pages. This you have to give to the place you want to present the topic. You have to write the Abstrct in the IEEE format if they ask you to do so. IEEE format is like you have to have the specific size of the text eg. for the heading the font is 14for the sub heading the font is 12 and so on. you may check the detail from the PDF IEEE(i am not sure about this source.) Then you have to make the hard and the soft copy.One hard copy you have to submit to the place of the presentation.and one with you. Hard copy is the print pages of the detail of the topic(In this too you have to make the use of the IEEE format if specified. ) Soft copy it is the power presentation(PP)Do not write too much in the PP only the point. And explain them.If the introduction page in made them there is no need to give the introduction againMake the use of the body language and the facial expressions and also make a slide of the source you have collected all the information from
What is dominant recessive?
There is dominant and there is recessive. There is no dominant recessive. A dominant gene will always be expressed when present, such as in the homozygous dominant genotype (RR), or heterozygous genotype (Rr). A recessive allele is only expressed when the genotype is homozygous recessive (rr).
What are the circumstances under which dominant alleles will be expressed?
Dominant alleles are expressed when an individual has at least one copy of the dominant allele in their genotype. This means that even if there is a recessive allele present, the dominant allele will be the one observed in the phenotype. Dominant alleles mask the expression of recessive alleles when they are both present in an individual's genetic makeup.
A recessive trait can only be expressed when?
A recessive trait can only be expressed when an individual has two copies of the recessive allele, one inherited from each parent. If only one copy is present, the dominant allele will be expressed instead.
What are dominant alleles?
Dominant alleles are genetic variants that are expressed when present in a single copy in an individual's genotype, masking the expression of a recessive allele. In a heterozygous individual (having two different alleles for a gene), the dominant allele will determine the phenotype. Dominant alleles are represented by a capital letter in genetic notation (e.g., A).
What are alleles for a particular trait that are always expressed are said to be?
Dominant alleles. Dominant alleles will always be expressed in the phenotype, even if only one copy is present in the genotype.
Which statement best describes a dominate allele?
okay well the dominant form of an allele, is YO MOM she is the answer to all your problems and yea te va pegar con la mexican chancla
What only contributes to the phenotype when 2 copies are present?
Recessive alleles only contribute to the phenotype when two copies are present. This means that both copies of the gene must carry the recessive allele in order for it to be expressed phenotypically. If only one copy is present, the dominant allele will be expressed instead.
What is a dominent allele?
A dominant allele is an allele that can take over a recessive allele, so if you have a dominant allele and a recessive allele, then the offspring will most likely have a dominant allele over a recessive allele. The dominant allele is expressed over the recessive allele.
Why is a dominant allele called dominanat?
A dominant allele is called dominant because it expresses its trait even when only one copy is present in an individual's genotype. This means that if an individual has one dominant allele and one recessive allele for a particular gene, the dominant trait will be observed in the phenotype. This characteristic allows dominant alleles to mask the effects of recessive alleles, leading to the trait associated with the dominant allele being the one that is visibly expressed.
What is the genotype of a person who is a carrier of a autosomal recessive trait?
The genotype of a person who is a carrier of an autosomal recessive trait is typically heterozygous, meaning they carry one copy of the recessive allele and one copy of the dominant allele for that trait. This would be represented as Aa, with the lowercase "a" representing the recessive allele.
Is an allele that produces a trait in the heterozygous condition recessive?
No. A recessive allele will not be expressed phenotypically in the heterozygous state. A recessive allele can only be expressed phenotypically in the homozygous state.
Individual that has one copy of a expressed gene has a genotype known as?
Heterozygous.
