Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 55412
TLS Online TPP Program

#Question id: 1370

H. V. Wilson worked with sponges to gain some insight into exactly what was responsible for holding adjacent cells together. He exposed two species of differently pigmented sponges to a chemical that disrupted intercellular junctions, and the cells of the sponges dissociated. Wilson then mixed the cells of the two species and removed the chemical that caused the cells to dissociate. Wilson found that the sponges reassembled into two separate species. The cells from one species did not interact or form associations with the cells of the other species.

How do you explain the results of Wilson's experiments?

#Unit 4. Cell Communication and Cell Signaling

  1. The two species of sponge had different enzymes that functioned in the reassembly process.

  2. The molecules responsible for cell-cell adhesion (cell junctions) were irreversibly destroyed during the experiment.

  3. The molecules responsible for cell-cell adhesion (cell junctions) differed between the two species of sponge.

  4. One cell functioned as an organizer for each organism, thereby attracting only cells of the same species.

More Questions
TLS Online TPP Program

#Question id: 861

#Unit 1. Molecules and their Interaction Relevant to Biology

Alexander Varshavsky discovered, the half-lives of many cytoplasmic proteins vary with the identities of their N-terminal residues via the so-called N-end rule:-

A. Destabilizing N-terminal residues Asp, Arg, Leu, Lys, and Phe have half-lives of

i. Only 2 to 3 minutes,

B. Stabilizing N-terminal residues Ala, Gly, Met, Ser, Thr, and Val have half-lives of

ii. >10 hours in prokaryotes

iii. >20 hours in eukaryotes.

TLS Online TPP Program

#Question id: 860

#Unit 1. Molecules and their Interaction Relevant to Biology

Select true ‘T’ AND false ‘F’ about ubiquitinylation

I. These ubiquitin-like modifiers control processes as diverse as nuclear import,

II. Regulated by the ubiquitin-like modifier Sumo, and autophagy,

III. Regulated by the ubiquitin-like modifier Atg8.

IV. For a protein to be efficiently degraded, it must be linked to a chain of at least four tandemly linked ubiquitin molecules in which Lys 34 of each ubiquitin forms an isopeptide bond with the C-terminal carboxyl group of the following ubiquitin.
TLS Online TPP Program

#Question id: 654

#Unit 1. Molecules and their Interaction Relevant to Biology

Which pair represents different conformations?
TLS Online TPP Program

#Question id: 655

#Unit 1. Molecules and their Interaction Relevant to Biology

A change from one conformation of a molecule to another involves ________.
TLS Online TPP Program

#Question id: 656

#Unit 1. Molecules and their Interaction Relevant to Biology

The ________ is the single shape a protein adopts under physiological conditions.
TLS Online TPP Program

#Question id: 657

#Unit 1. Molecules and their Interaction Relevant to Biology

Structural proteins that typically assemble into large cables or threads to provide mechanical support to cells or organisms are classified as ________ proteins.