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#Question id: 2904


When the temperature of a solution of DNA is raised to near the boiling point of water, the optical density, (called absorbance) at 260 nm markedly increases, a phenomenon known as hyperchromicity. Which of the following properties gets changed due to subsequent denaturation of the DNA molecule?

#Unit 2. Cellular Organization
  1. The solutions of native DNA exhibit high viscosity because of the relatively rigid double helical, long and rod like character of DNA molecule. Denaturation causes a marked decrease in viscosity.

  2. Denaturation of DNA double helix can also be brought about by certain chemical agents such as urea and formamide. These chemical reagents enhance the aqueous solubility of the purine and pyrimidine groups.

  3. Double-stranded DNA shows a strong positive rotation which highly decreases with denaturation. This change is analogous to the change in rotation observed when the proteins are denatured.

  4. All of the above

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TLS Online TPP Program

#Question id: 10162

#Unit 6. System Physiology – Plant

Following are certain statements regarding C3, C4 and CAM plants

a.) The atmospheric CO2 assimilates into the single cell C4 cycle diatoms, C4 conc. Is higher at the external side where the C3 conc. Is higher at the internal side where the CO2 assimilation takes place and the transport to the vascular tissue

b.) In mitochondria, two molecules of glycine yield a molecule of serine with the concurrent release of CO2 and NH4+ by the successive action of the glycine decarboxylase complex Only

c.) Plant with the C4 metabolism need less rubisco than C3 plants to achieve a given rate of Photosynthesis

d.) CAM Plant PEP Case only active during the Dark due to its phosphorylation while C4 PEP Case active throughout the day

Which of the following combination from above statements are TRUE?

TLS Online TPP Program

#Question id: 26880

#Unit 10. Ecological Principles

At the time of first colonisation extinction is __A__ and immigration rate is__B___

TLS Online TPP Program

#Question id: 21243

#Unit 7. System Physiology – Animal

A 62-year-old Caucasian woman experienced a rapid onset of blurry vision along with loss of central vision. A comprehensive eye exam showed that she had wet age-related macular degeneration. The fovea of the eye

TLS Online TPP Program

#Question id: 12972

#Unit 10. Ecological Principles

Under  some  circumstances a  population  can  split  into  two  or  more  species  without  the  existence of  geographic barriers. All of the following genetically determined behaviours could provide conditions leading to speciation EXCEPT

TLS Online TPP Program

#Question id: 1461

#Unit 4. Cell Communication and Cell Signaling

Which of the following correctly describes a Philadelphia chromosome?