0
If yellow peas are dominant over green peas the offspring of a pure dominant and a pure recessive cross is?
Let Y represent the dominant allele, and yrepresent the recessive allele. Let us also assume that "pure" means homozygous for that trait ("pure' is not the usual term for this, "homozygous" is) So, the two genotypes of the parents of the cross are: Parent 1: YY Parent 2: yy To solve a problem like this, one always has to determine what kind(s) of gametes each parent can produce. Both parents are homozygous for their respective traits, so in this case, each parent can only produce one kind of gamete: Parent 1 can only produce Ygametes, and Parent 2 can only produce y gametes. Therefore, every one of their offspring will have the following genotype: Yy Since every one of the offspring of the cross carries a Y allele, and Y is dominant, all of the offspring will be yellow.
What else can I help you with?
What is the result of a cross between an individual who is homozygous dominant and another who is homozygous recessive for a trait?
All the offspring will be heterozygous with a phenotype showing the dominant trait. Let the alleles be H (dominant) and h (recessive). All the gametes from the first individual will be H, and from the other, h. Thus all the offspring must be Hh.
Suppose that two true breeding pea plants are crossed One of the pea plants always produces yellow pea pods and the other always produces green pea pods If green pea pods are dominant over yellow pe?
If green pea pods are dominant over yellow pea pods, all offspring from the cross will have green pea pods. This is because the dominant trait (green) will mask the recessive trait (yellow) in the heterozygous offspring. The genotype of the offspring will be heterozygous for the pod color trait.
What is the name for a cross between an individual of unknown genotype and a homozygous recessive?
A cross between a homozygous recessive and an individual of unknown genotype is called a test cross.The homozygous recessive can only pass on a recessive allele to the offspring, and so any recessive in the other parent will show up in the phenotype (detectable characteristics) of some of the offspring.
If you cross a homozygous dominant striped cat with a homozygous recessive spotted cat. What will be the phenotype of the hybrid offspring?
The phenotype of the hybrid offspring will be striped, as the dominant striped trait will mask the recessive spotted trait in this case. The genotype of the hybrid offspring will be heterozygous for the striped trait.
How do geneticists normally tell whether an organism exhibiting a dominant phenotype is homozygous or heterozygous?
They perform a test cross. A test cross takes the unknown genotype and crosses it with a known homozygous recessive. If the F1 generation is all dominant, then they know the organism was a homozygous recessive. If recessive offspring appear, then the organism was a heterozygote. As an example, consider a gene with two alleles, A and a, with Adominant. Now consider the test cross. The unknown genotype can only be one of two possibilities: AA (homozgous dominant) Aa (heterozygous) In a test cross,the unknown genotype is crossed with a known homozygous recessive. Since there are only two possible unknown genotypes, there can be only two possible results. First, consider the case of the unknown genotype being a homozygous dominant. The cross looks like this: AA X aa Remember that a homozygote for an allele can only produce one kind of gamete. In this case the homozygous dominant can only produce gametes with the allele A in them, while the homozygous recessive can only produce gametes with the recessive allele a in them. This means the F1 offspring can only be ONE genotype; Aa. Therefore, all of the offspring would have the dominant phenotype. Now consider the other possible cross, where the unknown genotype is heterozygous: AaX aa Remember that a heterozygote can produce two types of gametes. In this case, the unknown would produce gametes with the dominant allele A or the recessive allele a. The homozygous recessive would still only produce one kind gamete, with the recessive a allele. Therefore, we expect to see only two genotypes in the F1, Aa and aa, in equal proportions. In either case, only one test cross is needed to tell one immediately the nature of the unknown genotype. If all of the F1 are of the dominant phenotype, then the unknown genotype must be homozygous dominant; if a mixture of phenotypes appears in equal proportion, then the unknown genotype must be a heterozygote.
Mendel crossed a true green podded plant with a true yellow podded plant. All the offspring from this cross had green pods. Green is the?
Green is the dominant trait in this cross. Mendel's results demonstrate that when a dominant allele (for green pods) is present, it masks the effect of the recessive allele (for yellow pods), resulting in all offspring exhibiting the dominant phenotype. Thus, the true yellow podded plant contributes a recessive allele that does not express in the presence of the dominant green allele.
What is the likelihood of a recessive trait being expressed if your offspring is crossed with a homozygous dominant eye shape prove your answer in a cross?
If you cross a homozygous dominant individual (AA) with a heterozygous individual (Aa), the offspring will have a genotype ratio of 100% dominant phenotype (AA or Aa) and 0% recessive phenotype (aa). Therefore, if your offspring has a homozygous dominant trait (AA), the likelihood of expressing a recessive trait (aa) is 0%. The Punnett square for this cross would show all dominant traits, confirming that recessive traits cannot be expressed in this scenario.
What is the result of a cross between an individual who is homozygous dominant and another who is homozygous recessive for a trait?
All the offspring will be heterozygous with a phenotype showing the dominant trait. Let the alleles be H (dominant) and h (recessive). All the gametes from the first individual will be H, and from the other, h. Thus all the offspring must be Hh.
If a homozygous dominant is crossed with a homozygous recessive for a given trait the offspring will be?
The phenotype will show the dominant trait. All dominant traits mask recessive ones; If the genotype is heterozygous (One dominant and one recessive) the organism's phenotype will be dominant.
The probability of a homozygous recessive offspring resulting from a cross between two homozygous dominant individual is?
It depends on the parents. The parent could have two dominant genes which would give a 0% chance of the offspring being recessive. The only way that the offspring could have a recessive characteristic is if the both parents have one dominant and one recessive gene, a 25% chance. The chance that both parents would pass on the recessive gene (if they have one dominant and recessive gene) is also 25%, because there is a 50% chance for each parent.
What is crossing recessive with dominant?
Crossing a recessive trait with a dominant trait involves breeding an organism that expresses the dominant phenotype with one that expresses the recessive phenotype. In genetics, the dominant trait will typically mask the expression of the recessive trait in the offspring. This can help determine the genotype of the dominant organism; if any offspring exhibit the recessive trait, the dominant parent must carry a recessive allele. This type of cross is often used in Mendelian genetics to study inheritance patterns.
How would a recessive trait show up in a cross between two individuals with a dominant phenotype?
In a cross between two individuals with a dominant phenotype but carrying a recessive trait, the recessive trait would not be visibly expressed in the offspring (since they don't inherit two copies of the recessive allele). However, they would be carriers of the recessive trait, meaning they could pass it on to future generations.
What crosses will result in dominant phenotype offspring?
Don't give us the options then!! If one parent had 2 dominant genes then all offspring would have dominant phenotype, the same goes for both parents having dominant genes.
What cross should a scientist perform in order to determine if the organism is heterozygous or homozygous dominant?
The scientist should perform a test cross between the organism and a homozygous recessive organism. If all offspring show the dominant trait, the original organism is homozygous dominant. If some offspring show the recessive trait, the original organism is heterozygous.
Suppose that two true breeding pea plants are crossed One of the pea plants always produces yellow pea pods and the other always produces green pea pods If green pea pods are dominant over yellow pe?
If green pea pods are dominant over yellow pea pods, all offspring from the cross will have green pea pods. This is because the dominant trait (green) will mask the recessive trait (yellow) in the heterozygous offspring. The genotype of the offspring will be heterozygous for the pod color trait.
What is the name for a cross between an individual of unknown genotype and a homozygous recessive?
A cross between a homozygous recessive and an individual of unknown genotype is called a test cross.The homozygous recessive can only pass on a recessive allele to the offspring, and so any recessive in the other parent will show up in the phenotype (detectable characteristics) of some of the offspring.
Which genotype is used in a test cross?
In a test cross, one individual with a dominant phenotype but unknown genotype is crossed with a homozygous recessive individual. The genotype of the individual with the dominant phenotype can then be inferred based on the phenotypic ratios of the offspring.
