Genetic Gridlock: Punnett Square Quiz

Organisms that have two identical alleles (BB or bb) for a particular trait are said to be homozygous. This means that both alleles for that trait are the same, whether they are both dominant (BB) or both recessive (bb). Homozygous individuals are purebred for that trait and will always pass on the same allele to their offspring.

The percentage of plants that are CcPP can be determined by multiplying the percentage of plants that are heterozygous for the wrinkled allele (Cc) with the percentage of plants that are homozygous dominant for the purple color allele (PP). Since the wrinkled allele is represented by a dominant C and the smooth allele is recessive c, the percentage of plants that are Cc is 50%. Similarly, since the purple color allele is represented by a dominant P and the white color allele is recessive p, the percentage of plants that are PP is also 50%. Therefore, the percentage of plants that are CcPP is 50% (50% x 50% = 25%).

When a heterozygous tall pea plant (Tt) is crossed with a short plant (tt), the possible genotypes of the offspring are Tt and tt. Since tall (T) is dominant to short (t), both Tt and tt genotypes will result in a tall plant. Therefore, 50% of the offspring will be tall.

The person below would have a 75% probability of having no dimples because the given information states that "(A) means no dimples and (a) means dimples." Therefore, since the answer choice is (A), it indicates that the person does not have dimples, resulting in a 75% probability.

In this scenario, brown (B) is dominant over white (b) in foxes. When a homozygous brown fox (BB) is crossed with a white fox (bb), all the offspring will inherit one copy of the brown allele from the brown fox parent. As a result, all the offspring will have the brown phenotype, making the probability of white phenotype 0% and the probability of brown phenotype 100%.

Based on the Punnett square provided and the information about the genetics of pea plants regarding wrinkled texture and purple color, where:

"C" is the dominant allele for wrinkled texture,

"c" is the recessive allele for smooth texture,

"P" is the dominant allele for purple color,

"p" is the recessive allele for white color,

We can analyze the genotypes shown in the Punnett square to determine the percentage of pea plants that will exhibit both a wrinkled texture and a purple color.

Looking at the genotypes in the Punnett square:

For texture, we need at least one "C" allele to express a wrinkled texture (Cc or CC).

For color, we need at least one "P" allele to express a purple color (Pp or PP).

Let's review the genotypes provided in the square:

Each combination contains at least one "C" and one "P" allele, meaning all the resulting plants will be wrinkled and purple.

Given this information, the correct answer is:

100% of the pea plants will be wrinkled and purple.

To determine the probability of a pea plant being yellow and wrinkled, we need to consider the individual probabilities of each trait occurring together. 



Given that:

- "g" represents the allele for yellow peas

- "b" represents the allele for wrinkled peas



According to Mendelian genetics, the traits of pea plants segregate independently during gamete formation, assuming no linkage or other complicating factors. Therefore, the probability of a plant being yellow and wrinkled is the product of the probability of being yellow and the probability of being wrinkled.



From the information provided, it seems we are not provided with specific probabilities for each trait. Assuming Mendelian inheritance and independence of traits, the probability of being yellow (g) could be different from the probability of being wrinkled (b).



Without specific probabilities for each trait, we can't determine the probability of a pea plant being yellow and wrinkled. So, the correct answer would be: Can't be determined

Dominant: The trait that is expressed even if only one copy of the allele is present (yellow fur in this case).

Recessive: The trait that is only expressed if two copies of the allele are present (white fur).

Heterozygous: Having two different alleles for a trait (Yy).

Homozygous: Having two identical alleles for a trait (YY or yy).

Setting up the cross:

The heterozygous yellow-fur cat has the genotype Yy (one allele for yellow, one for white).

The white-fur cat has the genotype yy (two alleles for white).

Possible offspring genotypes:

When these cats mate, the possible combinations of alleles their offspring can inherit are Yy (yellow fur) and yy (white fur).

Punnett Square: A Punnett square can visually represent the possible combinations:

When a homozygous tall pea plant (TT) is crossed with a short plant (tt), the possible phenotypes (genotype) of the offspring are tall (Tt) and tall (TT). Since tall (T) is dominant over short (t), both of these phenotypes will exhibit the tall trait. However, the letters denote genotype and not phenotype. Therefore, the correct answer is tall.

When two heterozygous parents (Aa × Aa) are crossed, the Punnett square yields four possible combinations: AA, Aa, Aa, and aa. This results in a genotypic ratio of 1:2:1 — one homozygous dominant (AA), two heterozygous (Aa), and one homozygous recessive (aa). These outcomes show the 25% chance for AA, 50% for Aa, and 25% for aa. This genetic pattern is a classic example of Mendelian inheritance for a single trait, where dominant and recessive alleles segregate predictably