What is the most useful application of ultrasonography for diagnostic examination?

Correct Answer: C

Rationale: Ultrasonography is a medical imaging technique that uses sound waves to visualize internal body structures. It is particularly effective for examining soft tissues like organs, blood vessels, and fetuses. Choice A is incorrect because bones are better visualized using techniques like X-rays. Choice B is incorrect as air-filled organs like lungs are not well visualized with ultrasound due to air being a poor conductor of sound waves. Choice D is incorrect since ultrasonography cannot visualize structures at a microscopic level, as it is used for larger internal structures.

Correct Answer: B

Rationale: Magnetic resonance imaging, commonly known as MRI, is a non-invasive imaging technique used to visualize internal structures of the body. While it can be used to distinguish between normal and abnormal tissue, one of its common applications is to examine musculoskeletal injuries, such as an injured knee. Choice A has been corrected to mention 'normal and abnormal tissue' instead of 'normal and cancerous tissue' as MRI is not solely used for cancer detection. Choice C is incorrect as MRI can provide detailed images of various body parts, not just limited to the brain. Therefore, the correct answer is to examine an injured knee.

Correct Answer: B

Rationale: Cadaver dissection is not against the law in the U.S. In fact, cadaver dissection is a common practice in medical schools and research institutions for educational and research purposes. The correct answer is 'False' because there are specific regulations and ethical guidelines that govern the use of cadavers for dissection. Choice C, 'Not Sure,' is incorrect as the legality of cadaver dissection is a well-established fact. Choice D, 'None of the above,' is also incorrect as one of the provided options is indeed correct.

Correct Answer: B

Rationale: No, the statement that we know all there is to know about the structure and function of the human body is false. The human body is complex, and there is still much to discover and understand about its intricate functions. Science and medicine continue to make new discoveries and advancements in understanding the human body. Choice A is incorrect because it claims that we know everything, which is not true. Choice C is not the best answer as it implies uncertainty rather than acknowledging the ongoing research and discoveries in this field. Choice D is not the correct option as there is a definitive answer to the question.

Correct Answer: B

Rationale: The statement is false. Cells with similar functions do not aggregate into organelles. Organelles are specialized structures within cells that perform specific functions, such as the nucleus, mitochondria, and endoplasmic reticulum. Cells themselves are the basic structural and functional units of organisms, and organelles are located within cells to carry out various tasks. Therefore, cells do not aggregate into organelles, but organelles are found within cells to support their functions. Choices A, C, and D are incorrect as cells do not form organelles by aggregating based on similar functions.