Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 26810
TLS Online TPP Program

#Question id: 760

Which force can stabilize a DNA double-helix?

#Unit 1. Molecules and their Interaction Relevant to Biology

  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: 11544

#Unit 7. System Physiology – Animal

When a steroid hormone and a polypeptide hormone exert similar effects on a population of target cells, then ________.
TLS Online TPP Program

#Question id: 11545

#Unit 7. System Physiology – Animal

Growth factors are local regulators that ________.
TLS Online TPP Program

#Question id: 11546

#Unit 7. System Physiology – Animal

Steroid and polypeptide hormones typically have in common ________.
TLS Online TPP Program

#Question id: 11547

#Unit 7. System Physiology – Animal

A cluster of tumor cells that produces and secretes growth factors to induce surrounding cells to grow and divide is showing which type of cell-to-cell signaling?
TLS Online TPP Program

#Question id: 11548

#Unit 7. System Physiology – Animal

If a portion of the pancreas is surgically removed from a rat and the rat subsequently loses its appetite, one explanation is that the removed portion contains cells that secrete a chemical signal that somehow stimulates appetite. Given this scenario, what type of chemical signaling is occurring?
TLS Online TPP Program

#Question id: 11554

#Unit 7. System Physiology – Animal

What happens in a cell when adenylyl cyclase is activated?