This type of microscope enhances contrast between specimen and background but does not permit the visualization of intracellular structures.

Question

BlackTom AI · Accepted Answer

When evaluating microscopy techniques, I start by matching the description to what each method does.
Option 1: Dark Field. This technique enhances contrast by illuminating the specimen with oblique light so that only scattered light enters the objective, making the background dark and the specimen bright. It is particularly good for unstained cells and tiny details, and it typically does not allow visualization of intracellular structures in detail due to the diffuse bright appearance; the statement correctly notes enhanced contrast with background but limited visualization of intracellular components.
Option 2: Phase-Contrast. This method converts phase shifts in light passing through transparent specimens into differences in brightness, which greatly helps view cellular structures and intracellular details. The description given in the question says intracellular structures are not visualized well, which contradicts phase-contrast’s strength, so this option does not match.
Option 3: Confocal. Confocal microscopy uses point illumination and spatial filtering to produce high-resolution, optically sectioned images with good intracellular detail, often using fluorescent labels. Since the prompt states that intracellular structures cannot be visualized, confocal is inconsistent with that claim.
Option 4: Fluorescence. Fluorescence microscopy relies on fluorescent labels to reveal specific structures or molecules, providing strong intracellular detail where labeled targets are visible. The assertion that intracellular structures cannot be visualized does not align with fluorescence’s capabilities, so this option is inaccurate for the given description.
To summarize, the key clue is a method that improves contrast between specimen and background yet limits visualization of intracellular details; among the choices, dark field best fits this characteristic, whereas phase-contrast, confocal, and fluorescence are all designed to illuminate and resolve intracellular structures more clearly, which contradicts the statement.

This type of microscope enhances contrast between specimen and background but does not permit the visualization of intracellular structures.

查看解析

登录即可查看完整答案

类似问题

A photograph taken by means of a microscope is called a(n) .

The following image is of a diatom viewed under a light microscope. The line A—B spanned 64 EPU. The same distance on the student’s drawing of the diatom measured 80 mm. What is the length (in mm) of the scale bar required to represent 40 μm on the student’s drawing?

Which part of the compound light microscope helps in gathering and focusing light rays on the specimen to be viewed?

What is the total magnification produced by using a 40x objective and a 10x ocular in a microscope?

Assuming a constant (non-adjustable) light source power, identify the part of the microscope you would adjust to limit the amount of light entering the microscope. Select all that apply.

In order to be able to visualize the stain under a microscope, you need to use....

更多留学生实用工具

考试浏览器助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单