User:Eric Martz/Ramachandran Principle Quiz
From Proteopedia
< User:Eric Martz(Difference between revisions)
(26 intermediate revisions not shown.) | |||
Line 1: | Line 1: | ||
+ | The nine-question quiz below is offered to accompany the interactive [[Tutorial:Ramachandran principle and phi psi angles]], which is also available as a [http://tinyurl.com/RamachandranPrinciple Slideshow] and a [http://tinyurl.com/RamachandranPrincipleYoutube YouTube video]. | ||
+ | |||
<quiz display=simple> | <quiz display=simple> | ||
- | |||
- | {The number of phi and psi bonds in each amino acid in a polypeptide chain is: | ||
- | |type="[]"} | ||
- | - None | ||
- | - 1 | ||
- | + 2 | ||
- | - 3 | ||
- | - 4 | ||
- | - 5 | ||
- | ||The phi bond is between N and C<sub>α</sub>. The psi bond is between C<sub>α</sub> and the carbonyl carbon. | ||
{How many bonded atoms are required to constitute a | {How many bonded atoms are required to constitute a | ||
- | + | dihedral (torsion) angle, such as phi or psi? | |
- | |type=" | + | |type="()"} |
- None | - None | ||
- 1 | - 1 | ||
Line 20: | Line 12: | ||
+ 4 | + 4 | ||
- 5 | - 5 | ||
- | ||[[Image:Phi-angle.png|150px|right]] | + | ||[[Image:Phi-angle.png|150px|right]]The phi [http://biomodel.uah.es/model5/prot/diedros_en.htm dihedral (torsion) angle] is defined by (1) the carboxy carbon from the previous amino acid; (2) N in the amino acid containing the phi bond; (3) C<sub>α</sub> in the amino acid containing the phi bond; and (4) the carboxy carbon of the amino acid containing the phi bond. |
- | The phi angle is defined by (1) the carboxy carbon from the previous amino acid; (2) N in the amino acid containing the phi bond; (3) C<sub>α</sub> in the amino acid containing the phi bond; and (4) the carboxy carbon of the amino acid containing the phi bond. | + | |
{The number of phi and psi angles in an isolated amino acid (not in a polypeptide chain) is: | {The number of phi and psi angles in an isolated amino acid (not in a polypeptide chain) is: | ||
- | |type=" | + | |type="()"} |
- | + | + None | |
- 1 | - 1 | ||
- | + | - 2 | |
- 3 | - 3 | ||
- 4 | - 4 | ||
- 5 | - 5 | ||
+ | ||The phi angle involves the carboxy carbon of the previous amino acid in a polypeptide chain. The psi angle involves the N of the subsequent amino acid. Therefore an isolated single amino acid has neither phi nor psi angles. | ||
+ | {The number of atoms held into a geometric plane by a peptide bond is: | ||
+ | |type="()"} | ||
+ | - 3 | ||
+ | - 4 | ||
+ | - 5 | ||
+ | + 6 | ||
+ | - 7 | ||
+ | - 8 | ||
+ | ||[[Image:Peptide-bond-plane-6-atoms.png|150px]] | ||
+ | {'''Questions below may have <font color="red">more than one</font> correct answer.'''} | ||
- | { | + | {The peptide bond is unable to rotate because |
- | |type="[]" | + | |type="[]"} |
- | + | + | - It is a covalent bond. |
- | - | + | - It is a non-covalent bond. |
- | + | + | - Rotation would cause clashes. |
- | - | + | + It is a partially double bond. |
- | || | + | |
+ | {Phi and psi angles directly determine | ||
+ | |type="[]"} | ||
+ | - Primary structure. | ||
+ | + Secondary structure. | ||
+ | + Tertiary structure. | ||
+ | - Quaternary structure. | ||
+ | ||See [[Protein primary, secondary, tertiary and quaternary structure]]. | ||
+ | |||
+ | {Alpha helices are compatible with | ||
+ | |type="[]"} | ||
+ | - All possible phi-psi angle combinations. | ||
+ | + A limited range of phi-psi angle combinations. | ||
+ | - A limited range of phi angles with all possible psi angles. | ||
+ | - A limited range of psi angles with all possible phi angles. | ||
+ | ||See [http://bioinformatics.org/molvis/phipsi/index.htm#plot Ramachandran Plot]. | ||
+ | |||
+ | {Common secondary structures are energetically favored because | ||
+ | |type="[]"} | ||
+ | + They optimize main-chain hydrogen bonds. | ||
+ | - They represent all possible conformations. | ||
+ | - They maximize clashes between atoms. | ||
+ | + They minimize clashes between atoms. | ||
+ | |||
+ | {Overlap of [https://en.wikipedia.org/wiki/Van_der_Waals_radius van der Waals radii] | ||
+ | |type="[]"} | ||
+ | + Between two non-bonded atoms is called a ''clash''. | ||
+ | - Between two covalently bonded atoms is called a ''clash''. | ||
+ | - Occurring between two non-bonded atoms in a molecular model signifies an energetically favorable interaction. | ||
+ | + Is physically impossible between two non-bonded real atoms. | ||
+ | |||
+ | {In a Ramachandran plot, the dots cluster | ||
+ | |type="[]"} | ||
+ | - Where clashes occur. | ||
+ | + Where clashes do not occur. | ||
+ | + Where alpha helices occur. | ||
+ | + Where beta strands occur. | ||
+ | - Where alpha helices, beta strands, and turns do not occur. | ||
+ | + Where the phi and psi angles are energetically favorable. | ||
</quiz> | </quiz> | ||
+ | [[Category:Pages with quizzes]] |
Current revision
The nine-question quiz below is offered to accompany the interactive Tutorial:Ramachandran principle and phi psi angles, which is also available as a Slideshow and a YouTube video.