The amino acid side chain residues in an α helix point outwards away from the center of the helix. the amino acid side chain residues in an α helix point outwards away from the center of the helix. a. true b. false

The statement is true.

The α helix structure is stabilized by hydrogen bonds between the oxygen atom of the C=O and hydrogen atom of the N-H group of the amino acid four residues away. In the tightly coiled super helical structure the side chains or the -R groups point outward or away from the helical axis. The main reason for  such structure is to avoid steric hinderance due to heavy or bulky -R groups and to keep the α helix structure stable. The right handed  α helix is more stable than the left handed α helix as there is lesser steric hinderance between the side chain and the backbone.

you are certainly talking about this picture:

a: is the label of the white square, it is showing the  replication fork, formed by helicase (d) ==> so it is the site of dna separation and replication 

b: is a new dna brand that is following directly the replication fork, so it is continuous ==> built continuously from 5' to 3

c: dna polymerase cannot replicate dna on its own, it needs the of their proteins, and one of them plays the role of a clamp which fixes  the dna with the dna template and increases  the processivity of the enzyme. ==>   stops polymerase from falling off the  template.

d: is the enzyme responsible for forming the replication fork (helicase) ==> unwinds and separates dna into two strands

e: is the delayed strand, it is built  in the opposite sense of the helicase, so dna will be built in fragments ==> built  fragments from 5' to 3 joins

and finally f: is the enzyme that builds  the new dna strand (dna polymerase) ==>   adds nucleotides to make a new dna helix.

credit: gradman555p98x9p

read more on -

sodium i think the chemical element of atomic number 11, a soft silver-white reactive metal of the alkali metal group.