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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Biotechnology Eligibility Test Preparation

DBT BET JRF Exam 2016 Original Solved Question Paper with Answer Key (Download PDF)


DBT BET JRF Previous Year Solved Question Papers Download PDF

Original (original) Previous Year (old) Solved Question Paper of DBT BET JRF 2016 Examination (Department of Biotechnology- Biotechnology Eligibility Test – Junior Research Fellowship) with Answer Key and Explanations as PDF. DBT BET JRF aspirants can download the question paper as single PDF file for your exam preparation. Please feel free to inform us for any mistakes in the answer key provided.

To download the question paper as single PDF file, please click on the download button below.

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mcq biology

MCQ on Water: Physical and Chemical Properties; pH and Buffer Systems Part 3 (Biochemistry MCQ-13)


biochemistry MCQ Water Buffer 

(Sample/Model/Practice Questions for CSIR JRF/NET Life Science Examination, ICMR JRF Exam, DBT BET JRF Exam,, GATE BT and XL Exam, ICAR JRF NE Exam, PG Entrance Exam, JAM Exam, GS Biology Exam and Medical Entrance Exam)

(1). What is the molecular weight of water?

a.       10 g/mol
b.      15 g/mol
c.       18 g/mol
d.      20 g/mol

(2). What is the H+ ion concentration in pure water?

a.       1 X 10-7 m
b.      1 X 107 m
c.       1 X 10-14 m
d.      1 X 1014 m

(3). The equilibrium constant of ionization reaction of pure water is:

a.       1.8 X 10-14 M
b.      1.8 X 10-16 M
c.       1.8 X 10-7 M
d.      1.8 X 10-7 M

(4). The pH of pure water is neutral, the best explanation for this is:

a.       The pH of pure water is 7
b.      In pure water the concentration of H+ and OH are same
c.       Water do not contain free H+ or OH ions
d.      What will never ionize

(5). What is the concentration of OH ions in a solution with an H+ ion concentration of 1.3 X 10-4M?

a.       7.7 X 10-11 M
b.      7.7 X 10-10M
c.       1.4 X 10-11M
d.      1.4 X 10-10 M

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mcq biology

MCQ on Water, Hydrogen Bonds, pH Scale and Buffer Systems Part 2 (Biochemistry MCQ-12)


MCQ on Hydrogen Bond, pH Scale

(Sample/Model/Practice Questions for CSIR JRF/NET Life Science Examination, ICMR JRF Exam, DBT BET JRF Exam,, GATE BT and XL Exam, ICAR JRF NE Exam, PG Entrance Exam, JAM Exam, GS Biology Exam and Medical Entrance Exam)

(1). Bond length between H and O atoms in water is:

a.       0.00965 nm
b.      0.0965 nm
c.       0.965 nm
d.      9.650 nm

(2). The van der Waals radius of Oxygen atom in water molecule is

a.       1.2 Å
b.      1.4 Å
c.       1.6 Å
d.      1.8 Å

(3). At room temperature and atmospheric pressure, a single water molecule can be hydrogen bonded with __________ water molecules.

a.       3.4
b.      3.0
c.       2.4
d.      1.4

(4). Non polar molecules are insoluble in water. This is because:

a.       Non polar molecules are uncharged
b.      Non polar molecules cannot be ionized
c.       Non polar molecules are unable to form water-solute interaction
d.      Hydrogen bond formation is not possible with non-polar molecules

(5). Which of the following is the correct for the formation of a hydrogen bond? (Hydrogen bond is represented as ‘…’)

a.       – O – H – O – H – X
b.      – O – H … O – X
c.       – O – H … H – O – X
d.      – O – H … C – O – X

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mcq biology

MCQ on Water, pH and Buffer Systems Part 1 (Multiple Choice Questions in Biochemistry MCQ-11)


mcq on water chemical & physical properties

 (Sample/Model/Practice Questions for CSIR JRF/NET Life Science Examination, ICMR JRF Exam, DBT BET JRF Exam,, GATE BT and XL Exam, ICAR JRF NE Exam, PG Entrance Exam, JAM Exam, GS Biology Exam and Medical Entrance Exam)

(1). Water is liquid at room temperature, the most important reason for this is the:

a.  High boiling point of water
b.  High melting point of water
c.  High heat of vaporization of water
d.  Cohesive forces due to hydrogen bonds in water

(2). Water is a ___

a.  Polar solvent
b.  Non polar solvent
c.   An amphipathic solvent
d.   Non polar uncharged solvent

(3). Polar molecules can readily dissolve in water. This is because:

a.  Polar molecules can form hydrogen bonds with water
b.  Polar molecules can replace water-water interaction with more energetically favourable water-solute interactions
c.  Polar charged water can interact with the charge of polar molecules
d.  All polar molecules are amphipathic in nature

(4). Most important reason for the unusual properties of water is:

a. The covalent bonding pattern in water molecule
b.  The bond angle between the two hydrogen atoms in water
c.   Hydrogen bonding between water molecules
d.  Water can be immediately ionized at room temperature

(5). The H – O – H bond angle in water molecule is:

a.   104.0o
b.   104.5o
c.   105.0o
d.   105.5o

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