Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 56981
TLS Online TPP Program

#Question id: 4992

The existence of the phenomenon of exaptation is most closely associated with which of the following reasons that natural selection cannot fashion perfect organisms?

#Unit 11. Evolution and Behavior

  1. Natural selection and sexual selection can work at cross-purposes to each other.

  2. Evolution is limited by historical constraints.

  3. Adaptations are often compromises.

  4. Chance events affect the evolutionary history of populations in environments that can change unpredictably.

More Questions
TLS Online TPP Program

#Question id: 23155

#Unit 13. Methods in Biology

Match the following ions in column I with their relevant dyes column II.
Column I                                                       Column II
1. K+                                                                 a. Fura-2
2. Ca2+                                                             b. SNARF-1
3. H+                                                                 c. Ion potassium green
Which of the following options is correct?
TLS Online TPP Program

#Question id: 23152

#Unit 13. Methods in Biology

A fluorescent dye SNARF-1 that is sensitive to H+ concentrations can be used to monitor the cytosolic pH of 
1. Alkaline cells
2. Acidic cells 
3. Dead cells
4. Live cells
Which of the following options are incorrect?
TLS Online TPP Program

#Question id: 23151

#Unit 13. Methods in Biology

If the concentration of Ca2+ is high inside the cell and fura-2 dye is used to map the concentration which of the following conditions will prevail?
1. Fluorescence will decrease
2.  Fluorescence will increase
3. Emission of light at higher wavelength
4. Emission of light at lower wavelength
Which of the following options are correct?
TLS Online TPP Program

#Question id: 23148

#Unit 13. Methods in Biology

There are two proteins A and B to be visualized under fluorescence microscopy. Both of them are excited with same wavelength of light but A emits longer wavelength. Hence we can conclude that 
1. A is denser molecule than B
2. B is denser molecule than A
3. A is lighter molecule than B
4. B is lighter molecule than A
Which of the following option is incorrect?
TLS Online TPP Program

#Question id: 23141

#Unit 13. Methods in Biology

Resolution of a light microscope is 0.42nm at 300 wavelength of light. If the specimen is viewed under oil what is the refractive index?
TLS Online TPP Program

#Question id: 19467

#Unit 13. Methods in Biology

Eosin is an acidic dye which basically binds to which molecules?
1. DNA
2. Carbohydrate
3. Glutamic acid
4. Aspartic acid
5. Asparagine
Which combination of the above options are correct?