Structure
In terms of appearance, what is the biggest difference between RNA and DNA?
RNA is single stranded.
What are the four types of nitrogenous bases found in DNA?
Guadanine, adenine, thymine, and cytosine.
What bases pair to each other in DNA?
A -> T, G -> C.
Who first isolated DNA?
Friedrich Miescher.
What are the three components of a DNA nucleotide?
A deoxyribose sugar, a phosphate, and a nitrogenous base.
Which nitrogenous base does uracil replace in RNA?
Thymine.
What is complementary base pairing?
The specific pairing of nitrogenous bases in DNA and RNA, where adenine pairs with thymine (or uracil in RNA) and guanine pairs with cytosine.
What did Watson and Crick determine?
DNA's structure.
What are the two strands of DNA held together by?
Hydrogen bonds.
A pentose sugar is present in all nucleotides. Why is this sugar called "pentose?"
It has five carbon atoms.
What holds the DNA strands together?
Hydrogen bonds between complementary base pairs.
What tool did Watson and Crick use to deduce DNA's structure?
An X-Ray.
In an RNA nucleotide's structure, the pentose sugar is called ___.
A ribose.
What are the classifications of bases? (hint: dependent on their structure!)
Purines and pyrimidines: purines are bases that have two rings in their structure, while pyrimidines contain only one ring.
What is the difference between GC and AT base pairs?
GC have three hydrogen bonds, AT have two hydrogen bonds.
What did Watson and Crick build to visualise DNA's structure?
A 6-foot-tall DNA model out of metal scrap.
Why do the two strands of DNA run in opposite directions?
The two strands must run in opposite directions (i.e. be antiparallel) to each other in order for bases to be facing each other. The 3' and 5' refer to the exposed carbon (on the sugar) at the ends of the DNA chains.
What is the name of the covalent bond that forms between nucleotide units?
Phosphodiester
Guanine and cytosine are paired together in a DNA. Based on each ring count, what is each base classified as?
Guanine = Purine
Cytosine = Pyrimidine
The fact that DNA exists is strong evidence of another section in the curriculum. What section is this? (hint: it's a theory)
The evolution theory.