Most proteins denature at both high and low pH. At high pH, the ionization of internal tyrosines is thought to be the main destabilizing influence, whereas at low pH, the protonation of buried histidines. A titration curve for the unfolding of the enzyme ribonuclease is shown in Figure. Given the relation between the titration curves for protein unfolding and histidine protonation, which of the following conclusion can be drawn correctly?

A. The sharp transition in graph indicates a highly cooperative process; when the protein starts to unfold, it completes the process rapidly

B. The sharp transition in graph indicates a highly noncooperative process

C. Several buried histidines can ionize when the chain starts to unfold, so that when one goes, they all go together due to cooperative behaviour of protein folding

D. Buried histidine (pK of 4 in this example) becomes accessible to solvent, its pK will shift toward its normal value of 6, significantly steepening its titration curve.

#Question id: 3409

#Unit 11. Evolution and Behavior

All genetic drift arises from sampling error, but there are several different ways in which sampling error can arise as a following

a. Reduced population size

b. Founder effect

c. Genetic bottleneck

d. Mate choice

Which of the following above way cause sampling error in succeed generation?

#Question id: 3408

#Unit 11. Evolution and Behavior

New species originated via punctuated equilibrium having some characterstic feature

a. occur during cladogenesis from ancestral species

b. subpopulation of ancestral species transform in to new species

c. Morphological change is sudden and rapid

d. continuously change in their morphology

which above statement is correct

#Question id: 3407

#Unit 11. Evolution and Behavior

Natural selection can act in three main ways on a character, such as body size, that is continuously distributed. Following graph represent fitness and their relative body size after the exposure of natural selection at different way? Which of the above population influence to which type of natural selection?

#Question id: 3406

#Unit 11. Evolution and Behavior

If 50 Invidual migrate from population A (allelic frequency P= .70 and q = .30  to population B with density 950 individual and allelic frequency  p=.40 q= .60. What is allelic frequency of P allele of population B after migration?

#Question id: 3405

#Unit 11. Evolution and Behavior

Phylogenies can be used to test whether speciation has been sympatric or allopatric. Following figure shown a new species arises by allopatric speciation, its nearest relative will usually live in a different geographic area, such as in a nearby lake. Which of the following phylogenetic tree is correct?

#Question id: 3404

#Unit 11. Evolution and Behavior

A graph shows the frequency distribution of the character (body size). B graph shows the relation between body size and fitness, within one generation, and the third the expected change in the average for the character over many generations (if body size is inherited). Which of the following correct figure for Average size with respect to time?