Lecture 14- Nucleic Acids Flashcards
What are the two types of nucleic acids? What are the monomers of nucleic acids?
Deoxyribonucleic acid and ribonucleic acid.
The monomers are nucleotides.
What are the differences between the two types of nucleic acids?
They differ in their pentose sugars (ribose vs deoxyribose) and in the nitrogenous bases they use.
What is the composition of the nucleotides and what is the function of each part?
Pentose sugar: backbone.
Nitrogenous base: where information is stored.
Phosphate group: link between succeeding nucleotides.
Where are nucleotides attached together? (What carbon and functional group).
Always starting at the 5’ carbon towards the 3’ carbon. New nucleotides add to the 3’ carbon.
The 3’ is the OH end and the 5’ is the P end.
How is the information coded into nucleic acids?
Information is coded in the sequence of bases.
How are the two strands of DNA oriented and attached? Do they have the same message?
The two strands are anti-parallel, and they are attached using hydrogen bonds between the nitrogenous bases. They each contain a different message but they are complementary.
What are the different functions of RNA?
RNA can transfer the message of DNA through mRNA, it makes up the ribosomes (rRNA), and carries amino acids to the ribosomes (tRNA).
What are the characteristics of the purines and which nucleotides fall into that category?
Purines contain two rings. They are Adenine and Guanine.
What are the characteristics of the pyrimidines and which nucleotides fall into that category?
They possess only one ring. They are Cytosine, Thymine, and Uracil.
Who proved that traits can be passed from the dead and what was their experiment?
Frederick Griffith. He used 2 strains of bacteria, one virulent and the other not. When he mixed dead virulent strands with live non-pathogenic ones, the bacteria still killed the mice.
What is transformation?
The uptake of DNA fragments in bacteria.
What did Colin Macleod, Oswald Avery, and Maclyn Mccarthy’s experiments proove?
It proved that proteins, lipids, and RNA were not inherited, and concluded that DNA could be inherited. (It did not prove this).
What did Hershey and Chase prove in 1952?
They proved that DNA is inherited by showing how Phage DNA is passed on to bacteria.
What did Erwin Chargaff do?
He made some progress with discovering the composition of DNA. He found that the proportion of A and T were the same, and that the proportion of C and G were also the same, leading to the AT and GC base pair theory.
What did Watson, Crick, and Franklin work on?
Using X-ray diffraction patterns to determine what DNA and other molecules look like.
They suggested a semi-conservative DNA replication mechanism.
