Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 37857
TLS Online TPP Program

#Question id: 760

Which force can stabilize a DNA double-helix?

#I Life Science/ Life Sciences Group – I-V

  1. Hydrophobic bases are found in the interior of the helix where each base pair is stabilized by the same number of hydrogen bonds.

  2. Hydrophilic sugar-phosphate groups are found on the exterior of the helix where they can interact with water.

  3. Non-covalent N-glycosidic bonds can form between nitrogenous bases in opposite strands in the helix.

  4. Covalent base-stacking interactions can occur between adjacent bases within the same strand in the helix.

More Questions
TLS Online TPP Program

#Question id: 3036

#SCPH28 | Zoology

During which phase would penicillin, an antibiotic that inhibits cell-wall synthesis, be most effective?
TLS Online TPP Program

#Question id: 5584

#SCPH01 Biochemistry

Which one of the following provides rapid block to polyspermy during sea urchin fertilization?
TLS Online TPP Program

#Question id: 9254

#SCPH28 | Zoology

Organisms evolve over generations to become adapted to the environmental conditions to which they are exposed. The diversity of organisms that
occurs in any particular area thus may be largely determined by the abiotic factors limiting survivorship and reproduction of organisms in a region. Which of the following limit the range of Saguaro cactus in North America?

I) pollinators

II) sunlight

III) precipitation

IV) temperature
TLS Online TPP Program

#Question id: 7768

#SCPH01 Biochemistry

The insulin signaling pathway inhibits the synthesis of the Foxo transcription factor proteins that would otherwise increase cellular longevity. Downregulation of the insulin signaling pathway has several other functions, choose right one
TLS Online TPP Program

#Question id: 18617

#SCPH06 I Botany

Both the metal ion used in PCR have different functions