Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 1008
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

#Unit 4. Cell Communication and Cell Signaling

  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: 2299

#Unit 2. Cellular Organization

_______ are plastids containing carotenoid pigments, and _______ are plastids containing starches.
TLS Online TPP Program

#Question id: 3255

#Unit 11. Evolution and Behavior

The body weight of offspring of bird species is range between 12 gm to 18 gm. In a laboratory experiment, species was subjected to selection pressure having influence on the offspring body weight. After many generations of experimental selection pressure, the body weight range between 16 gm to 24 gm. Which of the following natural selection operate on this species?
TLS Online TPP Program

#Question id: 24611

#Unit 2. Cellular Organization

Choose which of the following statement regarding Tetrahymena and mouse
a. Tetrahymena micronucleus have 5 no. chromosomewhile macronucleus having 225 no. chromosome
b. Tetrahymena macronucleus have 5 no. chromosome while micronucleus having 225 no.chromosome
c. Mouse have 20 haploid set chromosomes
d. Mouse have 20 diploid set chromosomes
TLS Online TPP Program

#Question id: 1263

#Unit 4. Cell Communication and Cell Signaling

The major classes of CAMs include

a. cadherins.    b. fibronectin.    c. Ig-superfamily CAMs.      d. P-selectins.
TLS Online TPP Program

#Question id: 3518

#Unit 8. Inheritance Biology

Assume that the trihybrid cross AA BB rr X aa bb RR is made in a plant species in which A and B are dominant but there is incomplete dominance between R and r. Consider the F2 progeny from this cross, and assume independent assortment. The phenotypes appear in this F2 progeny?