#Question id: 4655
#Unit 11. Evolution and Behavior
Over evolutionary time, many cave-dwelling organisms have lost their eyes. Tapeworms have lost their digestive systems. Whales have lost their hind limbs. How can natural selection account for these losses?
#Question id: 4656
#Unit 11. Evolution and Behavior
Logically, which of these should cast the most doubt on the relationships depicted by an evolutionary tree?
#Question id: 4657
#Unit 11. Evolution and Behavior
Which of the following statements most detracts from the claim that the human appendix is a completely vestigial organ?
#Question id: 4658
#Unit 11. Evolution and Behavior
Members of two different species possess a similar-looking structure that they use in a similar fashion to perform the same function. Which information would best help distinguish between an explanation based on homology versus one based on convergent evolution?
#Question id: 4659
#Unit 3. Fundamental Processes
Many bacterial responses are controlled by two component regulatory systems. What will happen at the high concentration of glutamine and at the low concentration of glutamine?
a) At high concentrations glutamine binds to a sensor domain of NtrB conformational change in the protein that inhibits its histidine kinase activity
b) NtrC phosphorylation takes place causes a conformational change in NtrC that unmasks the NtrC DNA-binding domain so that it can bind to the glnA enhancers
c) At the same time, the regulatory domain of NtrC blocks its DNA-binding domain from binding the glnA enhancers
d) At low concentrations of glutamine dissociates from the sensor domain in the NtrB protein, leading to activation of a histidine kinase transmitter domain
Which of the following given combination is correct?
#Question id: 4660
#Unit 3. Fundamental Processes
Two-component system regulating response to low Gln,
a) Glutamine dissociates from the sensor domain in the NtrB protein, leading to activation of a histidine kinase transmitter domain in NtrB
b) glutamine binds to a sensor domain of NtrB, causing a conformational change in the protein that inhibits its histidine kinase activity, the regulatory domain of NtrC blocks its DNA-binding domain from binding the glnA enhancers.
c) Activated transmitter domain of NtrB that transfers the γ-phosphate of ATP to a histidine residue (H), this phosphohistidine then transfers the phosphate to an aspartic acid residue (D) in the NtrC protein
d) This causes a conformational change in NtrC that unmasks the NtrC DNA-binding domain so that it can bind to the glnA enhancers
Which of the following combination is correct?