What is the length of a 71.0 kDa single‑stranded α‑helical protein segment? Assume a mean residue mass of 110 Da .

Answer : The  length of protein will be, 96.8 A⁰  

Explanation :

First we have to calculate the amino acid residue.

Given:

Length of single strand of protein = 71.0 kDa

Mean residue mass = 110 Da

Now we have to calculate the number of turns in protein.

As there are 3.6 amino acid per turn of the alpha-helix.

Now we have to calculate the length of the protein.

As, we know that the length of each turn = 0.54 A⁰

Thus, the length of protein will be, 96.8 A⁰

"among the transition metal elements, manganese and zinc have a slight lowering of electronegativities. the reason behind this is that the nuclear charges of these elements are slightly weaker than the other transition metal elements due to the way their valence electrons are filled up. both manganese and zinc have their valence electrons filled up to the 4th shell with 1 pair of electrons (4s2) completely occupying it. although the electrons in the 3rd shell (3d) are yet to be paired since the outer most shell is filled up, the ability of the nucleus to attract electrons is lessened. hence,   the electronegativity (or the ability to attract electrons) is lessened."

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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