In a DNA strand, 80% of the strand is made up of adenine and thymine. How much adenine, thymine, cytosine, and guanine is made up in the strand

The perecentage of guanine is 30%

Explanation:

According to the Chargaff's rules the DNA from any cell of all organisms should have a 1:1 ratio (base Pair Rule) of purine bases [for the DNA cytosine, thymine and for the RNA uracil] and pyrimidine bases [guanine and adenine for RNA and DNA]. The amount of guanine should be equaled to cytosine and the amount of adenine should be equaled to thymine. You can follow this rule in both strands of the DNA.

Explanation:

I don't know about the others sorry!

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

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