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Question 1

Beta strands are characterized by extended, non-coiled polypeptide chains
whose N-H and C=O groups do not X with neighboring amino acids
residues (as in the case of alpha helices) but with X

Answer 1

H-bond, residues in neighboring
strands.

Question 2

X are aligned in both
parallel and anti-parallel beta strands. This
allows “pleated” sheet structure in beta stands. If these carbons
aren’t aligned then
X

Answer 2

Alpha carbons, the sheet won’t be
as pleated.

Question 3

The X of a parallel beta strand are
never facing one another (when drawn out
using shorthand).

Answer 3

R groups

Question 4

The R groups of an anti-parallel beta sheet
are projecting X the plane
of the sheet.

Answer 4

above and below

Question 5

One X can hydrogen bond in an anti-parallel fashion with one
beta strand, and in a parallel fashion (simultaneously) with another strand.

Answer 5

beta strand

Question 6

Beta sheets can be comprised of between X polypeptide chains.

Answer 6

2 and ~20

Question 7

Beta sheets often have a right handed twist along the axis X to the
beta strand.

Answer 7

perpendicular

Question 8

The first and last strand of a beta-sheet can X and form
a beta-barrel

Answer 8

hydrogen bond

Question 9

A typical beta-strand contains 6 X; a typical beta sheet contains 6 X

Answer 9

residues, strands.

Question 10

Parallel beta sheets are rarely found with X strands; thus parallel might be less
stable or favored than anti-parallel.

Answer 10

> 5

Question 11

1. The alpha helix is X handed
   N
   C

Answer 11

right

Question 12

2. The X of the nth X
   H-bonds with the X of the
   n+4 Xin a X\n alpha helix

Answer 12

backbone N-H , residue , backbone C=O, residue

Question 13

The X has a dipole (due to the aggregate effect of the aligned C=O group

Answer 13

alpha helix