Multiple choice questions

[_Luna_]

Hey, I have some multiple choice questions that's bother me. I'll try translating them hoping someone could give me an answear.

 

1. Hydrophobic interaction in protein is giving important stabilization contributions

 

a) to proteins secundary- and tertiarystructure.

b) just to the orientation of polar amino acids

c) to the proteins primarystructure

d) after every possible hydrogenbonding are formed

e) only in hydrophobic fases

I am here guessing a or d, but I am very uncertain.

 

2. The structural membraneproteins are characterized in case of that they

 

a) don't transport small molecules

b) exist only by beta sheets

c) show prostetic carbohydrate groups on the cytoplasmatic side

d) have a hydrophobic transmembrane domain

e) constitue about 10% of the membrane proteins

 

Small molecules doesn't use transportproteins so it could be d, but again I'm not certain.

 

3. In watery solutions proteins conformation is decided by two factors: A maximum of the number of hydrogenbonding and:

 

a) a minimize av entropy by the formation of a watery shell around the protein

b) a rotation off polar amino acid residues out against the outer shell off the protein

c) a rotation off hydrophobic amino acids sidechains towards the centre of the protein

d) minimize off hydrophobic interactions

e) maximize of ion interaction

 

Here I actually don't have a clue, but someone told me it could be a?

[Gyrase]

1- Why you chose d? some hydrogen bondings take place between residues far apart in primary structure, how do you think these far residues are supposed to find each other?

2- why not

3- in watery solutions all hydrophobic residues tend to go inside the tertiary structure and maximizing hydrophobic interactions. Hydrogen bonding between surface residues and water is also very important.(I'm not sure if you have translated it correctly or not but rotation per se is not a determining factor but if it means going toward center and maximizing hydrophobic interactions then it is c)