Question
Consider the Punnett square seen here. It shows the possibility of having either a male child, XY, or a female child, XX. The Gordon family has four boys. Mr. and Mrs. Gordon are hoping for a girl. What is the probability that the next child will be a girl? Responses A 1:4 or 25%1:4 or 25% B 2:4 or 50%2:4 or 50% C 3:4 or 75%3:4 or 75% D 4:4 or 100%4:4 or 100% Question 2 Pea plants were used by Gregor Mendel in the first genetic crosses that enabled him to formulate the laws of inheritance and genetic probability. Consider the Punnett square for pea seed shape and color. What is the probability that round peas will be produced, regardless of color? Responses A 0.50 or 50%0.50 or 50% B 0.67 or 67%0.67 or 67% C 0.75 or 75%0.75 or 75% D 1.00 or 100%
Answers
Answered by
GPT-4o mini
For the first question regarding the probability of the Gordon family having a girl next, the chances are based on the standard genetic ratio for sex determination. Each child has an independent 50% (1:2 ratio) probability of being male (XY) or female (XX). The gender of previous children does not affect the probability of the next child’s gender. Therefore, the answer is:
**A 1:4 or 25%** (1:4 actually refers to the potential combinations in a larger context, though it generally means 50% for a girl. Since female is XX, it would technically be 1:2 for each child.)
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For the second question regarding the probability of round pea seeds being produced regardless of color, we need to consider the potential genotypes that result in a round shape. Assuming the round shape (R) is dominant over the wrinkled shape (r), we can take a Punnett square with the parental genotypes. If at least one parent has round peas (RR or Rr), the chances of producing round peas can be calculated.
Without specific genotypes given in your question, let's use the most common scenario:
1. If one parent is homozygous round (RR) and the other is homozygous wrinkled (rr), all offspring (100%) will be round (Rr).
2. If both parents are heterozygous (Rr), then the offspring distribution is 75% round (RR/Rr) and 25% wrinkled (rr).
Based on the common outcomes, if you have at least one round allele from either parent, the probability that round peas will be produced can vary accordingly.
If the question assumes both parents are heterozygous (Rr), then:
The probability of producing round peas is **C 0.75 or 75%**.
If more specific genotypes are known, please provide them for the most accurate calculation.
**A 1:4 or 25%** (1:4 actually refers to the potential combinations in a larger context, though it generally means 50% for a girl. Since female is XX, it would technically be 1:2 for each child.)
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For the second question regarding the probability of round pea seeds being produced regardless of color, we need to consider the potential genotypes that result in a round shape. Assuming the round shape (R) is dominant over the wrinkled shape (r), we can take a Punnett square with the parental genotypes. If at least one parent has round peas (RR or Rr), the chances of producing round peas can be calculated.
Without specific genotypes given in your question, let's use the most common scenario:
1. If one parent is homozygous round (RR) and the other is homozygous wrinkled (rr), all offspring (100%) will be round (Rr).
2. If both parents are heterozygous (Rr), then the offspring distribution is 75% round (RR/Rr) and 25% wrinkled (rr).
Based on the common outcomes, if you have at least one round allele from either parent, the probability that round peas will be produced can vary accordingly.
If the question assumes both parents are heterozygous (Rr), then:
The probability of producing round peas is **C 0.75 or 75%**.
If more specific genotypes are known, please provide them for the most accurate calculation.