All of the following statements are true about meiosis, except: answer choices: During prophase I of meiosis, chromosomes pair tightly to form tetrads, the prophase I stage of meiosis can last several years in humans. Crossing over takes place between non-homologous chromosomes. the end of meiosis in a diploid organism, each daughter cell is haploid. Chromatin replicates prior to meiosis 3) Suppose that a cross of rabbits yields a 15:1 black:white fur ratio. If there are two redundant genes that code for black color, what is the genotype of the white rabbit? answer choices: aabb, aaBb, AaBb, Aabb, not enough info 4) if the critical cut off value for a chi-square test is 3.14 and the chi-square value you calculate from your experimental data is 6.79, what can you determine about your hypothesis? Answer choices, The hypothesis can be accepted, the degrees of freedom are too narrow, there is a 95% chance that the hypothesis is correct, the hypothesis can be rejected Only need answers for checking my work 🙂 thank you
The Correct Answer and Explanation is:
1. All of the following statements are true about meiosis, except:
Correct answer: Crossing over takes place between non-homologous chromosomes.
2. Genotype of the white rabbit (15:1 ratio):
Correct answer: aabb
3. Chi-square test result (critical value = 3.14, observed = 6.79):
Correct answer: The hypothesis can be rejected.
Explanation
In meiosis, prophase I is a crucial stage where homologous chromosomes pair up closely to form tetrads. This allows for crossing over, a process where genetic material is exchanged between homologous chromosomes, not non-homologous ones. This mixing of genes increases genetic diversity. The statement claiming that crossing over happens between non-homologous chromosomes is false, since non-homologous chromosomes do not share corresponding loci and do not align in tetrads. That makes this the correct “except” answer.
The 15:1 ratio in the rabbit cross suggests duplicate dominant epistasis. This means that either gene A or gene B can produce black fur. Only the double recessive genotype (aabb) lacks both dominant alleles, leading to the white fur phenotype. All other combinations (AaBB, AaBb, AAbb, etc.) produce black fur because at least one dominant allele is present. So, the only genotype that would result in a white rabbit is aabb.
For the chi-square test, the critical value of 3.14 at a certain degree of freedom (often 1) is used as a threshold. If the calculated chi-square value (6.79) is greater than the critical value, this means the difference between observed and expected results is statistically significant. Therefore, the null hypothesis must be rejected because the deviation is too large to be due to chance. This suggests that some factor besides random variation is influencing the results.
Each of these answers is based on fundamental genetic principles and standard statistical interpretation
