Protein kinases are enzymes that transfer the terminal phosphate from atp to an amino acid residue on the target protein. many are located on the plasma membrane as integral membrane proteins or peripheral membrane proteins. what purpose may be served by their plasma membrane localization?

a) atp is more abundant near the plasma membrane.
b) they can more readily encounter and phosphorylate other membrane proteins.
c) membrane localization lowers the activation energy of the phosphorylation reaction.
d) they flip back and forth across the membrane to access target proteins on either side.

The tasmanian devil, a marsupial carnivore, is facing extinction due to devil facial tumor disease (dftd) which causes bulging cancerous lumps and lesions to erupt around the face and neck — often causing enough deformation to make seeing or eating difficult. dftd has evolved into a contagious cancer, a trait that is unique among cancers. devil mating behavior involves biting around the head and neck, allowing cells from one individual — especially cells from the crumbly dftd tumors — to be transferred to the wounds or face of a new individual. this marsupial was once found across australia, but sea levels rose, isolating the tasmanian population, while the australian population went extinct. what would be an outcome of genetic isolation that is likely to have impacted the spread of dftd? a) reduced territory puts diseased individuals in greater contact with non-diseased ones. b) inbreeding results in less variation in facial features so the cancer is generally fatal. c) genetic isolation has made it difficult for scientists to develop a vaccine against dftd. d) the lack of genetic variation in the immune system of tasmanian devils minimizes resistance to the disease.

Anormal strand of dna is shown below, followed by the same strand of dna after mutations have occurred.

Dna, in the nucleus carries the genetic code for making proteins in ribosomes. in the diagram, b, represents the proteins produced. dna cannot leave the nucleus to carry the genetic information to the ribosome where proteins are produced. how does the genetic code get from the nucleus to the ribosome? what does a represent? now