The microscope in cell studies

The microscope in cell studies

The Microscope in Cell Analysis

  • Microscopes allow us to visualise minute biological structures, aiding us in understanding the complexity of cells.
  • There are three main types of microscopes used in cell biology: the light microscope, the transmission electron microscope (TEM) and the scanning electron microscope (SEM).

Light Microscope

  • The light microscope uses light to illuminate the sample, generating a magnified image on a screen or photographic film.
  • It has a relatively low resolution, so it can’t resolve smaller structures like individual ribosomes.
  • However, it allows for the viewing of living samples and processes over time, like mitosis.

Transmission Electron Microscope (TEM)

  • The TEM works by transmitting a beam of electrons through a very thinly sliced specimen.
  • TEMs have a high resolution and can magnify up to two million times, revealing minute cellular structures.
  • However, they can’t be used to image living cells or tissues, as samples have to be fixed, dehydrated, and embedded in resin.

Scanning Electron Microscope (SEM)

  • The SEM emits a beam of electrons onto the surface of a specimen causing secondary electrons to bounce off and form a 3D image.
  • SEM provides a three-dimensional view of the specimen surface, but with lower resolution compared to TEM.
  • Similar to TEM, SEM requires extensive sample preparation rendering the samples unusable for studying live processes.

Electron Microscopy vs Light Microscopy

  • Both electron microscopes (TEM & SEM) allow for much higher resolution and magnification than light microscopes, revealing far more cellular detail.
  • However, they require more extensive sample preparation and cannot be used to study living specimens.
  • Understanding the strengths and weaknesses of each type of microscope allows for their effective use in cell biology.