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For the cross in Part B, predict the frequencies of each of the phenotypes in the F1 progeny, and determine the genotype(s) present in each phenotypic class.

The genotype-phenotype distinction must be drawn when trying to understand the inheritance of traits and their evolution. The genotype of an organism represents its exact genetic makeup, that is, the particular set of genes it possesses. Two organisms whose genes differ at even one locus (position in their genome) are said to have different genotypes. The transmission of genes from parents to offspring is under the control of precise molecular mechanisms. The discovery of these mechanisms and their manifestations began with Mendel and comprises the field of genetics.

The term "genotype" refers to the full hereditary information of an organism. The phenotype of an organism represents its actual physical properties, such as height, weight, hair color, and so on. It is the organism's physical properties that directly determine its chances of survival and reproductive output, while the inheritance of physical properties occurs only as a secondary consequence of the inheritance of genes.


A Monohybrid cross is a cross between individuals who are identically heterozygous at one locus, for example, Bb x Bb (see the Punnett square below).

Monohybrid inheritance is the inheritance of a single characteristic. The different forms of the characteristic are usually controlled by different alleles of the same gene. For example, a monohybrid cross between two pure-breeding plants (homozygous for their respective traits), one with yellow seeds (the dominant trait) and one with green seeds (the recessive trait), would be expected to produce an F1 (first) generation with only yellow seeds because the allele for yellow seeds is dominant to that of green. A monohybrid cross compares only one trait.

Monohybrid Cross in Punnett Square

Generally, dominant characteristics are represented with a capital letter, e.g. B, and recessive characteristics are represented by a lower case letter, e.g. b.

B b

B BB Bb

b Bb bb

For a monohybrid cross, the parental genotypes are homozygous, and their progeny, now the F1 generation, are all heterozygous. The above table, a Punnett square, illustrates the results of a cross between two F1 heterozygous individuals. The result is a 1:2:1 genotypic ratio, and a 3:1 phenotypic ratio

Hello! I'm new here, so I'm just getting the hang of the forum, but this is the diagram given for the question. I'm also having some trouble figuring it out.

Hi there, the question needs to be posted word-for-word (typed).

Oh, thank you for letting me know! The question is:
For the cross in Part B, predict the frequencies of each of the phenotypes in the F1 progeny, and determine the genotype(s) present in each phenotypic class.
Complete the diagram by dragging the correct label to the appropriate location. Labels can be used once, more than once, or not at all.

The diagram question is attached in the previous post, but since this question is in reference to part B, part B's question was:
A plant grown from a [round, yellow] seed is crossed with a plant grown from a [wrinkled, yellow] seed. This cross produces four progeny types in the F1:
[round, yellow], [wrinkled, yellow], [round, green], and [wrinkled, green].
Use this information to deduce the genotypes of the parent plants.
The answer to this was RrYy, and rrYy. If you need me to post the diagram for part B ,let me know! I hope this cleared it up a bit!

Check out the attachment...

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thanks a bunch!

Monohybrid inheritance is the inheritance of a single characteristic. The different forms of the characteristic are usually controlled by different alleles of the same gene. For example, a monohybrid cross between two pure-breeding plants (homozygous for their respective traits), one with yellow seeds (the dominant trait) and one with green seeds (the recessive trait), would be expected to produce an F1 (first) generation with only yellow seeds because the allele for yellow seeds is dominant to that of green. A monohybrid cross compares only one trait.

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