Tag: cell and cellular organization

Questions Related to cell and cellular organization

Fluorescent screen or photographic plate is used for observation in

  1. Electron microscope.

  2. Fluorescent microscope.

  3. Ultraviolet microscope.

  4. All of the above.


Correct Option: D

In which of the following microscopes direct observation is not possible?

  1. Compound microscope

  2. Dark field microscope

  3. Phase contrast microscope

  4. Ultraviolet microscope


Correct Option: D

Fluorescent microscope employs

  1. UV rays

  2. Visible light

  3. Beam of electrons

  4. Both A and B.


Correct Option: D

Lenses used in ultraviolet microscope are

  1. Glass lenses.

  2. Quartz fluorite.

  3. Lithium fluoride.

  4. Both B and C.


Correct Option: D

Stop disc is meant for

  1. Blocking light.

  2. Stopping objective in pressing slide.

  3. Altering light rays.

  4. Splitting light rays.


Correct Option: A

Stop disc is used in which microscope?

  1. Compound light microscope

  2. Differential interference contrast microscope

  3. Dark field microscope

  4. Phase contrast microscope


Correct Option: C
Explanation:

A stop is an opaque object that blocks the central light when placed underneath the stage condenser. This also causes light to scatter in all azimuths, resulting in a cone of light that allows for dark field observation.

So C is correct option. 

Detailed structure of biological molecules can be known with the help of _____________.

  1. Atomic force microscope.

  2. Scanning probe microscope.

  3. Scanning tunneling microscope.

  4. All of the above.


Correct Option: A

A living cell can be best studied by the means of______________.

  1. Dark field microscope.

  2. Electron microscope.

  3. Phase-contrast microscope.

  4. Compound microscope.


Correct Option: C
Explanation:

Phase Contrast Microscope was developed by Zernike. The microscope has a phase plate and an annular diaphragm. They bring about changes in light rays passing through the specimen producing differences in light intensity. Denser parts alter path of light more than the thinner parts. This produces varying contrast for different regions. Hence, staining is not required and the difference between denser and lighter parts of the specimen is revealed by the phase difference. The microscope is useful in the study of small living organisms, living cells, constituents of living cells, effect of various factors over living structures, and study of various cellular events like behaviour of chromosomes during mitosis and meiosis, spindle formation, cytokinesis, pinocytosis, phagocytosis, cyclosis, glandular secretions, spermatogenesis, oogenesis etc.

So C is the correct option. 

Fluorescent microscope uses _______________.

  1. UV radiations.

  2. Complementary filters.

  3. Annular diaphragm.

  4. Both A and B.


Correct Option: D

Light is split into two beams in

  1. Fluorescent microscope.

  2. Differential interference contrast microscope.

  3. Phase contrast microscope.

  4. Dark field microscope.


Correct Option: B