Tag: spectrophotometer, colorimeter and biosensor

Questions Related to spectrophotometer, colorimeter and biosensor

Isopycnic or equal density centrifugation is achieved in

  1. Buoyant density centrifugation

  2. Density gradient centrifugation

  3. Electrophoresis

  4. Differential centrifugation


Correct Option: B

Which of the following statement can be related to colorimeter?

  1. It is a light sensitive device

  2. It is used to measure the absorbance

  3. It is used to measure the transmittance

  4. All of the above


Correct Option: D
Explanation:

A colorimeter is a light-sensitive device user to measure the transmittance and absorbance of light passing through a liquid sample. It measures the intensity or concentration of the color that develops after adding a specific reagent to a solution. The working of colorimeter is based on Beer-Lambert law which states that absorption of light transmitted through the medium is directly proportional to the medium concentration.

So,  the correct answer is 'All of the above'

On which of the following laws the working of the colorimeter is based upon? 

  1. Blackman's law of limiting factor

  2. Beer Lambert law

  3. Hill's reaction

  4. None of the above


Correct Option: B
Explanation:

A colorimeter is a device that measures the absorbance and transmittance of different wavelengths of light in a solution. This is called Beer-Lambert law. 

The measurement is aided by adding a particular reagent to the solution so that the solution acquires a particular color and of a certain intensity.
So, the correct answer is 'Beer Lambert law'

In which of the following types of centrifugation, the components of separation are based on size, shape and density?

  1. Differential centrifugation

  2. Zonal centrifugation

  3. Density gradient centrifugation

  4. All of the above


Correct Option: A
Explanation:

In differential centrifugation particles of different density, size and shape in a suspension sediment at different rates, with the larger and denser particles sedimenting faster. These sedimentation rates can be increased by using centrifugal force. Thus the correct answer is 'Differential centrifugation'.

The technique which is used in the separation of plant cell wall 

  1. Electrophoresis

  2. Ultracentrifugation

  3. Gel filtration Chromatography

  4. Magnetic Separation


Correct Option: B
Explanation:

Ultracentrifugation is a technique used to separate plant cell wall.

Which technique is used in separating proteins from other fractions?

  1. Chromatography

  2. Autoradiography

  3. Electrophoresis

  4. Ultracentrifugation


Correct Option: D

Which of the following compounds used in density gradient centrifugation?

  1. Cholesterol

  2. Sucrose

  3. Glycine

  4. DNA


Correct Option: B

Which of the following is generally used for creating density gradient during centrifugation?

  1. NaCl

  2. KCl

  3. CsCl

  4. $MgCl _2$


Correct Option: C

Cells obtained from an organism were homogenised and centrifuged. A test indicated that the cells contained glycogen. If you are asked to find out as quickly as possible whether the cells were from a plant or an animal, you would

  1. Examine the centrifuge for presence of extracts of centrioles

  2. Answer immediately that the cells were from an animal source

  3. Examine the centrifuge for the presence of extracts of chloroplasts

  4. Answer immediately that the cells were from a plant source.


Correct Option: B

In order to sediment free ribosomes, centrifugation is required to be done at

  1. 300,000g

  2. 50,000g

  3. 12,000g

  4. 800g


Correct Option: A