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: 3601

#Unit 8. Inheritance Biology

In cucumbers, dull fruit (D) is dominant over glossy fruit (d), orange fruit (R) is dominant over cream fruit (r), and bitter cotyledons (B) are dominant over non-bitter cotyledons (b). The three characters are encoded by genes located on different pairs of chromosomes. A plant homozygous for dull, orange fruit and bitter cotyledons is crossed with a plant that has glossy, cream fruit and nonbitter cotyledons. The F1 are intercrossed to produce the F2. What will be expected proportions progeny with Dull, Orange and non-bitter?

#Question id: 3602

#Unit 8. Inheritance Biology

Mendel crossed Yellow, round and tall pea plants ( YYRRTT) with green, wrinkle and dwarf ones ( yyrrtt). The F1 plants were all yellow, round tall. These F1 plants were cross with YyrrTT. Which of the following proportional of phenotype in progeny?

#Question id: 3603

#Unit 8. Inheritance Biology

Blue follower is dominant over white flower and long pollen is dominant over short pollen. A plant with Blue flower and short pollen was cross with white flower and long pollen. Their progeny, ½ had a blue flower with long pollen and another ½ had a white flower with long pollen was allowed to intercross. Which of the following observation is correct among these progeny when independently assort?

#Question id: 3604

#Unit 8. Inheritance Biology

Genes A, B and C. control three phenotypes which assort independently; A plant with the genotype aaBbCc were cross with AabbCc. What is the probability for progeny which show the dominant phenotype for AT LEAST ONE of the phenotypes controlled by genes A, B and C?

#Question id: 3605

#Unit 8. Inheritance Biology

Male Plant blue flower with long pollen was crossed with female plant white flower with long pollen. Analysis of progeny of this cross showed that 50% of the progeny was red with long pollen while the remaining 50% of the progeny was white with long pollen. Which one of the following statements is a possible explanation of the above results?

#Question id: 3606

#Unit 8. Inheritance Biology

Genes A, B and C. control three phenotypes which assort independently; A plant with the genotype Aa Bb Cc is selfed. What is the probability for progeny which show the heterozygocity for AT LEAST ONE locus?