NCERT Class 11 Biotechnology Chapter 12 Answer English Medium | Tools and Technologies

Chapter 12

Tools and Technologies

Exercises

1. The function of ethidium bromide in electrophoresis is to

(a) Track the progression of electrophoresis

(b) visualise the DNA molecules

(c) separate the DNA molecules

(d) provide charge to DNA molecules

Answer:

2. Match the following

3. Mass spectrometry is used to

(a) identify unknown compounds

(b) elucidate the structure of molecules

(c) quantify compounds

(d) All of the above

Answer:

4. Match the following table with reference to Antigen

5. In DNA gel electrophoresis,

I. Longer DNA fragments remain close to the well.

Answer:

II. Longer DNA fragments move towards the positive end of gel.

Answer:

III. Smaller DNA fragments move close to the positive end of gel.

Answer:

IV. Smaller DNA fragments remain close to the well. Which of the above options are correct

(a) I and III

(b) II and IV

(c) Only II

(d) None of the above

Answer:

6. For a resolved image of the surface of an object, which of the following microscopes would you prefer

(a) Transmission electron microscope

(b) Scanning electron microscope

(c) Phase contrast microscope

(d) Fluorescence microscope

Answer:

7. Match the following:

8. Which of the following techniques is feasible to quantify the expression of a large number of genes

(a) Mass spectrometry

(b) Microarray

(c) FISH

(d) Agarose gel electrophoresis

Answer:

9. Differentiate between the following types of microscopy techniques

(a) Scanning electron microscopy (SEM) and transmission electron microscopy (TEM)

(b) Dark field microscopy and bright field microscopy

(c) Phase contrast microscopy and confocal microscopy

Answer:

10. Discuss the principle of agarose gel electrophoresis.

Answer:

11. Name a tracking dye which is used to track DNA as well as proteins during electrophoresis. What will happen if you forget to add tracking dye to your sample during electrophoresis?

Answer:

12. Two polyacrylamide gels A and B were prepared. Gel A had 4% acrylamide whereas Gel B had 12% acrylamide. Based on the given information answer the following

(a) Which gel is harder: A or B?

(b) Which gel offers greater friction to the proteins: A or B?

(c) Which gel (A or B) will be used to separate a mixture containing low molecular weight proteins?

(d) Which gel (A or B) will be used to separate a mixture containing both low and high molecular weight proteins?

Answer:

13. What is a chromatogram? Draw a well labeled diagram of a chromatogram of a mixture containing three different solutes.

Answer:

14. Explain the principle of FISH. How is FISH technique applied in chromosome painting? What are the advantages of chromosome painting?

Answer:

15. Mention the various applications of spectroscopy techniques.

Answer:

16. What are major components of UV-visible spectrophotometer? Explain each in brief.

Answer:

17. Write the major differences between the Sanger’s method and Maxam and Gilbert’s method of DNA sequencing.

Answer:

18. Write the principle of flow cytometry.

Answer: