What makes genetics hard?

Correct Answer: D

Rationale: The correct answer is D because genetics is complex and multifaceted. 1. A: Presence of a gene not defining phenotype shows gene-environment interactions. 2. B: Hidden genes in carriers illustrate the concept of genetic variability. 3. C: Both parents' contributions are crucial due to inheritance patterns. Combining these reasons, genetics is challenging due to its intricate nature encompassing gene-environment interactions, genetic variability, and inheritance patterns.

Correct Answer: B

Rationale: The correct answer is B: Both parents contribute a "haploid" gamete. In Mendelian genetics, offspring inherit one set of chromosomes from each parent, resulting in a combination of genetic material from both parents. This process involves the fusion of haploid gametes during fertilization, leading to genetic variation in the offspring. This fundamental principle of genetic inheritance is crucial in understanding Mendel's laws of segregation and independent assortment. A: Genes code for proteins - This statement is true but not the basis of Mendelian genetics. The relationship between genes and proteins is important but not specific to Mendelian genetics. C: One parent's genome is dominant - This statement is incorrect. Dominance is a concept related to gene expression, not the basis of Mendelian genetics. D: Genes can skip generations - This statement refers to non-Mendelian inheritance patterns, such as incomplete dominance or epistasis, which do not align with the basic principles of Mendelian genetics.

Correct Answer: D

Rationale: The correct answer is D because the Hardy-Weinberg equation requires all the conditions mentioned in choices A, B, and C to be met for a population to be in genetic equilibrium. Choice A ensures genetic diversity, choice B ensures no natural selection, and choice C ensures no gene flow from other populations, which are all essential for the equation to be valid. Therefore, the correct answer is D as it encompasses all necessary conditions.

Correct Answer: D

Rationale: The correct answer is D, "All of the above." Chromosome aberrations can arise through breakage, which may occur due to various factors such as errors during DNA replication or exposure to mutagens. Recombination can also lead to chromosome aberrations when there are errors in the exchange of genetic material between chromosomes. Additionally, radiation can cause chromosome aberrations by inducing DNA damage. Therefore, all the choices (A, B, and C) are valid mechanisms through which chromosome aberrations can arise.

Correct Answer: C

Rationale: The correct answer is C: It is a non-invasive technique. Ultrasound is safe and non-invasive, making it ideal for prenatal screening as it does not pose any risk to the mother or the fetus. Choices A and B are incorrect because ultrasound must be performed by a trained healthcare professional in a medical setting, not at home, and it requires specialized equipment and expertise, making it more expensive and reliant on advanced technology. Choice D is incorrect as choices A and B are not true, making it not all of the above.