What type of tissue will appear dark on an x-ray as it allows x-rays to pass through?

The correct answer is that radiolucent tissue will appear dark on an x-ray, as it allows x-rays to pass through. In radiological imaging, radiolucency refers to areas of the image that do not absorb X-rays and thus appear darker. This occurs because radiolucent tissues have lower density compared to surrounding structures, meaning they do not obstruct the passage of X-rays effectively.

Fat is an example of radiolucent tissue; therefore, it will show up dark on an X-ray. Other types of tissue, such as muscle and connective tissue, are also considered radiolucent but to a varying degree. In contrast, radiopaque tissues, such as bone or metal, absorb X-rays more effectively and appear white or light on the radiograph, as they are denser and prevent the passage of X-rays through them.

Cortex refers to the outer layer of an organ or structure (such as the bone cortex) and may contain both radiopaque and radiolucent areas, depending on its composition. Understanding the distinction between these types of tissues is essential for interpreting X-rays correctly in a clinical setting.