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Terms in this set (8)OBJECTIVES ... OBJECTIVES A. Relate the kinds of microscopes used to study cells. microscope. vision with the unaided eye has limitations. The smallest objects we can resolve, or identify as separate objects, are approximately 100 um, or 0.1 mm, in diameter, approximately the size of a fine pencil dot. The details of cells and tissues, which are much smaller than 100 um, cannot be examined without the aid of a microscope. microscopes types Two basic types of microscopes (1) light microscopes (2) electron microscopes. names imply, light microscopes use light to produce an image, electron microscopes use beams of electrons to produce an image. resolution of light microscopes is limited by the wavelength of light, lower limit being approximately 0.1 µm-about the size of a small bacterium. Light microscopy regularly used to examine biopsy specimens because samples can be quickly prepared and the resolution is adequate to diagnose most conditions that cause changes in tissue structure. most tissues are colorless and transparent when thinly sectioned, the tissue must be stained with a dye, so that the structural details can be seen, or must be stained with antibodies that recognize specific molecules. The bound antibodies are detected by fluorescent tags. An electron microscope used to see objects much smaller than a cell. An electron microscope, has a limit of resolution of approximately 0.1 nm, about the size of some molecules. transmission electron microscope (TEM), beam of electrons is passed through the object to be viewed; whereas, in scanning electron microscope (SEM), beam of electrons is reflected off the surface of the object. For TEM, the specimen must be embedded in plastic and thinly sectioned (0.01-0.15 um thick). The magnification ability of SEM is not as great as that of TEM; however, the depth of focus of SEM is much greater and produces a clearer three-dimensional image of tissue structure. advantages of SEM, atomic force microscope (AFM). A newer type of microscopy, which expands on the advantages of SEM, is the atomic force microscope (AFM). This type of microscope scans the sample using a tiny mechanical probe that can be deflected by small forces between the probe and sample. This generates a three-dimensional surface map of the sample. AFM combines the high resolution of TEM with the topographical visualization of SEM. AFM also has the benefit that samples can generally be viewed under more physiological conditions. Because TEM, SEM, and AFM do not transmit color information, the micrographs are black and white unless assigned false colors. ASSESS YOUR PROGRESS 3. Whic cell features can be seen with a light mircoscope? Other sets by this creator3.4 Membrane Lipids9 terms the_ghost_studies 3-3 Plasma Membrane8 terms the_ghost_studies 3-1 Functions of Cell41 terms the_ghost_studies 3 Cell Biology Intro2 terms the_ghost_studies Other Quizlet setsA.P. U.S. Gov Terms and Test Questions Chpt. 157 terms AudreyH2301Plus Lecture 8: CT (extracellular matrix and…29 terms cnesiba0Plus Psych 320 - Chapter 315 terms Lonee_Schoenfeldt Chemistry Chapter 2 Study Guide32 terms Stevie_Angel What are the smallest cell structures that can be seen by a light microscope?In practical terms, bacteria and mitochondria, which are about 500 nm (0.5 μm) wide, are generally the smallest objects whose shape can be clearly discerned in the light microscope; details smaller than this are obscured by effects resulting from the wave nature of light.
Which of the following is the smallest structure?The smallest structural and functional unit of an organism is a cell.
Is used to describe the smallest structure capable of performing all of the necessary functions for life?The cell is the smallest unit of living matter capable of performing all the activities necessary for life (Alberts et al. 1994). In fact is the smallest structure with a complete metabolism because it has all the physical and chemical components needed for its own maintenance and growth.
Which of the following is the smallest structure quizlet?Cells-smallest structural and functional unit of an organism Flashcards | Quizlet.
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Which term is used to describe the smallest structure that can be seen by a light microscope quizlet?
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