How can the phenotypes of two pea plants with different genotypes for seed color be identical? A. One of the two plants may be homozygous for the dominant allele, while the other may be homozygous for the recessive allele.B. One of the plants may be homozygous for the dominant allele, while the other may be heterozygous.C.
How can two plants with distinct flower color genotypes have similar phenotypes?
Genetic Variation | National Geographic Society In one sense, ” genotype ” is synonymous with ” genome ” in that it refers to the full collection of genes in the cells of an organism. However, in a broader sense, it can refer to distinct alleles, or variant versions of a gene, for certain qualities or features.
- The genotype of an organism is distinct from its phenotype, which consists of the individual’s observable features that come from interactions between the genotype and the environment.
- The relationship between genetics and phenotype is intricate.
- Since the phenotype is the product of the interaction between genes and the environment, various environments might result in distinct characteristics in people with a given genotype.
Additionally, various genotypes might result in same phenotypes. This occurs because genes include distinct alleles. Specific alleles are dominant for certain genes and characteristics, whereas others are recessive. A dominant trait is one that manifests in an individual even if only one allele”allele that creates the characteristic is present.
- This is how several parts of eye color function.
- For example, brown eyes predominate over blue eyes.
- This is because a pigment known as melanin forms brown eyes, but the absence of pigment results in blue eyes.
- Having a single allele for the dark pigment is sufficient to produce brown eyes.
- There are in fact several pigments that influence eye color, each pigment arising from a specific gene.
This is why people can have green eyes, hazel eyes, and a variety of other eye hues than blue and brown. Biologists use capital letters to represent dominant alleles and lowercase letters to represent recessive alleles when discussing genotype. Regarding eye color, for example, “B” represents a brown allele and “b” represents a blue allele.
- Homozygous dominant genotype describes an organism with two dominant alleles for a certain characteristic.
- Using the example of eye color, this genotype is represented as BB.
- The genotype of an organism with one dominant and one recessive allele is referred to as heterozygous.
- In our example, this genotype is represented by the letters Bb.
The genotype of an organism containing two recessive alleles is known as homozygous recessive. In the instance of eye color, this genotype is denoted as bb. Only bb, the homozygous recessive genotype, will yield the phenotype of blue eyes among these three genotypes.
Both the heterozygous and homozygous dominant genotypes result in brown eyes, but only the heterozygous genotype may transmit the gene for blue eyes. Some genes and characteristics cannot be explained by the homozygous dominant, homozygous recessive, and heterozygous genotypes. Numerous genes have more than two alleles, and many alleles interact in various ways, therefore the majority of characteristics are really more intricate.
Genetic Variation | National Geographic Society
Hint: The term phenotype refers to the observable physical characteristics of an organism, including its development, appearance, and behavior. A genotype is the entirety of an organism’s genetic makeup. However, genotype can also refer to a single gene or a group of genes.
- Phenotypes are the observable characteristics of an individual, such as height, eye color, and blood type.
- The genotype is the genetic contribution to the phenotype.
- Some qualities are predominantly influenced by the genotype, whereas others are mostly affected by environmental circumstances.
- A genotype is the collection of an individual’s genes.
Additionally, the phrase can refer to a particular gene for the two alleles inherited. When protein and RNA molecules are synthesized utilizing the information contained in the DNA of the genes, the genotype is expressed. Due to the existence of a dominant allele, it is conceivable to have the same phenotype yet different genotypes.
- When a dominant allele is present in the genotype, it is always expressed.
- A person may have a dominant allele on both homologous chromosomes, whereas another individual may have a single dominant allele and a matching recessive allele.
- In both instances, the characteristic regulated by the dominant allele will be manifested.
There will be no phenotypic distinction as a result. All creatures, including plants, exhibit this phenomena. A dominant allele is a variant of a gene that will generate a certain phenotype regardless of the existence of other alleles. When a dominant allele is completely dominant over another allele, the other allele is termed recessive.
- Recessive alleles only manifest their influence when a person possesses two copies of the allele.
- Consequently, due to the existence of dominant alleles in the genotype of organisms, phenotypes look same despite genotype differences.
- In humans, the dominant eye color is manifested in both homozygous and heterozygous dominant individuals.
Two mice that appear almost similar may have different genotypes. However, if one mouse has white hair and the other has black fur, they have distinct phenotypes.
What explains the various colors of pea seeds?
Keeping Green Peas Widespread – Its genes contain the instructions for producing a pea plant. Each gene contains the instructions for a certain pea plant component. There is a gene that influences the hue of peas produced by a plant. Genes can exist in variant forms.
- The pea “color” gene is available in yellow (Y) and green (G) forms (y).
- Pea plants, like humans, have two copies of the majority of their DNA.
- This indicates that there are three potential color gene combinations: It is obvious that YY pea plants produce yellow peas, as they possess exclusively the yellow form of this gene.
And those yy pea plants exclusively produce green peas since they have just the green kind. What about pea plants that have one of each variety? How many pea plants do you have? The peas are yellow because the dominant yellow variant, Y, is stronger than the recessive green form, y.
- Y always triumphs over y: When a pea plant produces seeds, only one of its two copies of the color gene is transferred to each seed.
- Therefore, if you have two green pea plants, only one of them may pass the green version.
- Meaning that all of their seeds will produce pea plants with green peas.
- The same thing occurs when a pea plant with green peas self-pollinates to produce seeds.
The plant can only pass on green versions, hence the seed will only contain green versions. And two green variants correspond to green peas. Therefore, green peas are prevalent despite being recessive. If we exclusively breed pea plants that produce green peas, only green pea-producing pea plants will be produced.
