Chapter four: Flashcards
(22 cards)
What are considered Nucleic acids?
DNA and RNA
What nucleotide is used to make DNA and RNA?
sugars
Ribose
Deoxyribose
What is the difference between Deoxyribose and Ribose?
The second carbon of ribose is bonded to a hydroxide and the second carbon or deoxyribose is bonded to a hydrogen
What is a nucleotide?
a phosphate group bonded to a 5-carbon sugar.
The five carbon sugar is bonded to a nitrogenous base.
What are the different types of Nitrogenous bases?
pyrimidines- composed of a single hydro-carbon ring
Purines- double hydrocarbon ring
What of the nitrogenous bases is found in both DNA and RNA?
Cytosine, Guanine, Adenine
What of the nitrogenous bases is found only in RNA?
uracil
What of the nitrogenous bases is found only in DNA?
Thymine
What nucleotides are Pyrimidines?
Cytosine, uracil, Thymine
What nucleotides are Purines?
Guanine, Adenine
What is the ribose problem?
In experiments where the controlled setting is the pre-biotic earth, it is very difficult to get ribose’s to from
What is the pyrimidine problem?
n experiments where the controlled setting is the pre-biotic earth, it is very difficult to get pyrimidine’s to form, but is very easy to get purines to form.
T/f Nucleic acids are monomers of nucleotides?
F, they are polymers
How do nucleic acids form?
Condensation reactions: When a hydroxide on prime phosphate group forms a bond with the hydroxide on the previous chain of 3 prime carbons.
What is the result of the condensation reaction to form nucleotides?
phosphodiester linkage
What form of energy makes phosphodiester bonds?
The nucleotide that is about to be added: The energy comes from its activated form. Energy is released when the tri-phosphate bond is broken
What is Gel Electrophoresis?
allows for the separation and study of nucleic acids
Who was key in the discovery of the structure of DNA?
Francis Crik, James Watson, Maurice Wilkins, Rosalind Fraklin, Edwin Chargaff
What is DNA’s primary structure?
Single linear strand
Edwin Chargaff, what was he known for?
how the nucleotides of different organisms differed.
- discovered the ratio of purines:pyrimidines, guanine:cytosine, adenin:thymine
Maurice Wilkins what was she known for?
interested in structure: used X-Ray crytallography
-Discovered that DNA is a helix and the dimensions of it.
Francis CrikJames Watson, what was he known for?
They foud that two stands of DNA that had purines opposite of one anther, they wont fit within the width of the DNA molecule, and it would be difficult to stablize.
- A purine and a pyrimidine opposite of anther fit and bond well
- anti-parallel in direction
