Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 44676
TLS Online TPP Program

#Question id: 1033

 A research lab is trying to produce new antibiotics. They come up with drugs that detach the hydrophilic heads from the phospholipids in plasma membranes. This drug

#SCPH06 I Botany

  1. would be highly toxic and completely useless for human beings-we also have plasma membranes with hydrophilic head groups!

  2. would be highly toxic only to bacteria, making it an excellent drug to develop and test further. Humans have a different phospholipid structure in their cell plasma membranes than bacteria.

  3. would generally not be toxic enough to damage Gram-negative bacteria, as their plasma membranes lie under a thick layer of peptidoglycan.

  4. would be highly toxic for human beings, but might be useful as a topical antibiotic skin cream. The top layer of skin cells is dead anyway, so it wouldn't matter if this damaged those cells. It could NOT be taken internally, though, by human beings. 

More Questions
TLS Online TPP Program

#Question id: 10984

#SCPH28 | Zoology

Which of the following are caused by acetylcholine?
TLS Online TPP Program

#Question id: 599

#SCPH05 I Biotechnology

In a certain enzyme-catalyzed reaction the following steps occur:

1. A phosphate group on substrate A is transferred to a side chain of an active site residue of the enzyme.

2. The dephosphorylated form of substrate A dissociates from the enzyme.

3. Substrate B enters the active site and is phosphorylated with simultaneous regeneration of the enzyme in its original form.

What kind of kinetic mechanism is described?
TLS Online TPP Program

#Question id: 10349

#SCPH05 I Biotechnology

Elevated plastid levels of glutamine stimulate the activity of glutamate synthase (also known as glutamine:2- oxoglutarate aminotransferase, or GOGAT). Given below some of the statements about GOGAT, which one of the following is incorrect?
TLS Online TPP Program

#Question id: 3446

#SCPH28 | Zoology

Which of the following is least related to the others?
TLS Online TPP Program

#Question id: 1294

#SCPH05 I Biotechnology

Dystroglycan is a large glycoprotein that binds to dystrophin in muscle cells.  It is also present in other cells and can also bind to:

a.  laminin.

b.  the virus that causes Lassa fever.

c.  the bacterium that causes leprosy.