Light Microscope Vs Electron Microscope: Similarities and Differences- A Comparison Table


difference between light and electron microscope

There are more animals living in the scum on the teeth in a man’s mouth than there are men in a whole kingdom.
Antony van Leeuwenhoek

A microscope is an instrument used to see objects which are not directly visible to naked eyes. The word microscope is derived from the Latin word ‘micro’ (=small) and the Greek word ‘skopos’ (=to look at). The present decade’s development in science and technology produced varied types of microscopes with wide and diverse applications. Major credits for the current developments in biological sciences goes to the technological advancements in the field of microscopy which allowed scientists to visualize not only minute structural features but also many molecular and physiological pathways within the cells. The significance of microscopy in biological sciences if further evident when we see the history of Nobel Prize. Almost all types of microscope discoveries and their further advancements have been awarded with Nobel Prize. There are two fundamental types of microscopes; they are optical (light) microscopes which employ glass lenses and visible spectrum of light; and electron microscope which employ electromagnetic lenses and beam of electrons for image formation. This post is describes the similarities and fundamental differences between these two type of microscopes namely optical (light) microscope and Electron microscope.

Similarities between Light Microscope and Electron Microscope

Ø  Both microscopes are used for visualizing small objects which are not directly observable by naked eyes

Ø  Specimen preparations such as sectioning, staining mounting etc are required in both types of microscopes prior to observation

Ø  Both types of microscopes are used in research applications

Ø  Both microscopes follow Abbe’s law

Ø  Microphotography is possible with both microscopes

Difference between Light Microscope and Electron Microscope

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mcq biology

Biophysics MCQ: Electrophoresis: for JRF NET Life Science Examination (Biology MCQ 009): Biophysical Instrumentation: Separation Techniques Part 1


Biophysics Quizzes

Biology MCQ (Multiple Choice Questions in Life Science)
(Sample/Model/Practice Questions for JRF/NET Life Science Examination, ICMR JRF, DBT JRF, GATE, ICAR NET, PG Entrance)

Biophysical Instrumentation: Separation Techniques Part 1: (MCQ 009)


1). When voltage ‘V’ is applied across a pair of electrode (cathode and anode), a potential gradient ‘E’ is created between the electrodes. We can calculate ‘E’ as:

a.      E = V/d
b.      E = (1/V) x q
c.       E = (Vd)/q
d.      E = V + d

2). The velocity (‘v’) of a charged particles in an electric field in a medium can be mathematically expressed as v = Eq/f, where ‘Eq’ and ‘f’ are ________.

a.      Eq: Energy; f: Frictional force
b.      Eq: Electrical force; f: Gravitational force
c.       Eq: Electrical force; f: Frictional co-efficient
d.      Eq: Equilibrium constant; f: co-efficient of gravity

3). For the separation of DNA by electrophoresis, which of the following method is commonly used?

a.      Agarose – vertical
b.      Agarose – horizontal
c.       PAGE – vertical
d.      PAGE – horizontal

4). Sodium dodecyl sulfate (SDS) used in SDS PAGE is___________.

a.      An anionic detergent
b.      A cationic detergent
c.       A non-ionic detergent
d.      An anion exchanger
e.       A cation exchanger

5). Function of β-mercaptoethanol in SDS-PAGE is__________.

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