Why can FISH provide genetic information in the absence of spreads of mitotic chromosomes?

Correct Answer: B

Rationale: The correct answer is B because FISH (Fluorescence In Situ Hybridization) uses specific DNA probes that target a particular chromosome or chromosomal region. This allows for the visualization and analysis of specific genetic information without the need for spreads of mitotic chromosomes. Choice A is incorrect because FISH does not necessarily use DNA from whole chromosomes. Choice C is incorrect as chromosomes play a crucial role in genetic information. Choice D is incorrect because while chromosomes contain both DNA and protein, this is not the reason why FISH can provide genetic information without spreads of mitotic chromosomes.

Correct Answer: B

Rationale: Step-by-step rationale for why answer B is correct: 1. Difficulty getting pregnant is typically related to fertility issues, not necessarily genetic problems. 2. Genetic problems manifest in structural abnormalities, aberrant chromosomes, or inherited conditions. 3. Options A, C, and D all involve indicators of genetic issues through birth abnormalities or aberrant chromosomes. 4. Difficulty getting pregnant does not directly point towards a genetic problem but rather reproductive health issues.

Correct Answer: D

Rationale: The correct answer is D: Ultraviolet light. UV radiation has higher energy levels compared to visible light, infrared, and EMF, making it capable of damaging DNA and causing mutations that can lead to cancer. UV exposure is a known risk factor for skin cancer. Visible light and infrared do not have enough energy to cause DNA damage and cancer. EMF (electromagnetic fields) have not been proven to directly cause cancer. In summary, only UV light has the necessary energy to cause cancer, making it the correct choice among the options provided.

Correct Answer: B

Rationale: Step-by-step rationale for why answer B is correct: 1. Ionizing radiation is a natural phenomenon present in the environment. 2. It originates from sources like cosmic rays, radon gas, and certain minerals. 3. These sources contribute to background radiation levels worldwide. 4. Exposure to ionizing radiation from natural sources is unavoidable. 5. Therefore, choice B is correct as ionizing radiation is naturally present everywhere. Summary of why other choices are incorrect: A. Incorrect because ionizing radiation also occurs naturally. C. Incorrect as ionizing radiation is not limited to space but is present on Earth. D. Incorrect because ionizing radiation can have harmful effects, especially if not used properly or in excessive doses.

Correct Answer: D

Rationale: The correct answer is D: All of the above. Acute effects of air pollution can include bronchitis, cancer, and emphysema due to exposure to harmful pollutants. Bronchitis is inflammation of the bronchial tubes, cancer can be caused by carcinogenic pollutants, and emphysema is a lung disease often linked to air pollution. Therefore, all the choices (A, B, and C) are potential acute effects of air pollution. The other choices are incorrect because they do not encompass the full range of acute effects that can result from exposure to air pollution.