Tag: manipulation of dna

Quizzes (0) Questions (50)

Questions Related to manipulation of dna

Multiple choice bio-chemistry biochemical techniques manipulation of dna electrophoresis isolation and separation of dna

The technique used for separating molecules by passing electric current is

  1. Fractionation

  2. Centrifugation

  3. Electrophoresis

  4. ELISA

  5. Chromatography
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Electrophoresis is a technique, in which particles of different sizes and charges are separated due to their movement to different distances under the influence of an electric field, e.g : nucleic acid, proteins, amino acids, nucleotides etc.
Chromatography is a technique of separating molecular components of a mixture by using the principle of partition coefficient.
Cell fractionation is the technique of separating and rupturing cells and separating the cellular components for study. It has two steps - homogenisation (rupturing of cells) and differential centrifugation (separation of different components of homogenate). 
ELISA stands for Enzyme Linked immunosorbent Assay. It is an assay procedure used in diagnosis of AIDS.
Multiple choice bio-chemistry biochemical techniques manipulation of dna electrophoresis isolation and separation of dna

A method which uses paper or film with different electric poles at the two ends and is used for separation of charged particles is called

  1. Electrolysis

  2. Electrophoresis

  3. Electroplating

  4. Thin layer chromatography
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Electrophoresis is the technique used to separate charged particles (like DNA or proteins) by applying an electric field across a gel or medium.

Multiple choice bio-chemistry biochemical techniques manipulation of dna electrophoresis isolation and separation of dna

Escherichia coli, in which both the strands of DNA are labeled  with $^{15}N$ is transferred to $^{14}N$ medium and allowed to replicate for three generations. Find out the number of hybrid DNA molecules in the third generation

  1. 8

  2. 2

  3. 12

  4. 10
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In semi-conservative replication, the two original strands (15N) separate. After one generation, all DNA is hybrid (15N-14N). After two generations, there are 2 hybrid and 2 light (14N-14N) molecules. After three generations, there are 8 total molecules, but only 2 remain hybrid (the original strands are always part of a hybrid molecule).