Flocculation and Flotation

Q.

Read the following statements and find out the incorrect statements with reference to agarose gel electrophoresis.

(i) Now-a-days the most commonly used matrix is agarose which is a synthetic polymer extracted from sea weeds.

(ii) Larger the fragment size, the farther it moves.

(iii) We can not see pure DNA in UV light without staining.

(iv) DNA fragments separate (resolve) according to their size through sieving effect provided by the agarose gel

Q. Assertion: Flocculation is used for cell separation during downstream processing.
Reason: Density of cells remains same after flocculation.

1. [A] is true and [R] is false.
2. [A] is false and [R] is true .
3. Both [A] and [R] are true and [R] is a correct explanation to [A].
4. Both [A] and [R] are true but [R] is not a correct explanation to [A].

Q. Assertion: Floatation is an efficient technique to separate cells during downstream processing.
Reason: Bubbling of air through fermentation mix makes the biomass float on the surface along with foam.

1. [A] is false and [R] is true .
2. Both [A] and [R] are true and [R] is a correct explanation to [A].
3. Both [A] and [R] are true but [R] is not a correct explanation to [A].
4. [A] is true and [R] is false.

Q. The method developed by Matthew Meselson and Franklin Stahl to separate heavy DNA with, 15N from DNA with l4N, for providing evidence for semi-conservative replication of DNA is

1. ion exchange chromatography
2. density gradient centrifugation
3. isopycnic centrifugation
4. gel filtration

Q. Assertion: Flocculation is used for cell separation during downstream processing.
Reason: Density of cells remains same after flocculation.

1. [A] is true and [R] is false.
2. [A] is false and [R] is true .
3. Both [A] and [R] are true and [R] is a correct explanation to [A].
4. Both [A] and [R] are true but [R] is not a correct explanation to [A].

Q. Process of clumping cells together using inorganic salts or mineral hydrocolloids is called __.

Q. Assertion: Floatation is an efficient technique to separate cells during downstream processing.
Reason: Bubbling of air through fermentation mix makes the biomass float on the surface along with foam.

1. [A] is true and [R] is false.
2. [A] is false and [R] is true .
3. Both [A] and [R] are true and [R] is a correct explanation to [A].
4. Both [A] and [R] are true but [R] is not a correct explanation to [A].