Lesson 18: Nucleic Acid Structure Flashcards
What is the monomer of nucleic acids?
Nucleotides
What are the polymers of nucleic acids?
DNA: deoxyribonucleic acid
RNA : ribonucleic acid
What does DNA do?
Stores the hereditary information of a cell, genes are discrete units of hereditary information consisting of a specific nucleotide sequence
What does RNA do?
Assist in protein production
What are the components of a nucleotide?
Phosphate group, 5-carbon sugar (pentose), nitrogenous base (cytosine, guanine, adenine, thymine (DNA only) and uracil (RNA only)
What does deoxyribose lack in the pentose sugars?
Lacks a hydroxyl group on the second carbon
What are nitrogenous bases?
Carbon rings that also contain nitrogen
What are pyrimidines in nitrogenous bases?
Cytosine, thymine (DNA), and uracil (RNA)
What are purines in nitrogenous bases?
Adenine and guanine
Purines are PURE as gold so you want two of them
What are the complementary base pairings?
T:A (DNA), U:A (RNA)
C:G (both)
What is the numbering carbons?
Numbering of carbons in the sugar is important. The carbon double bonded to oxygen (the carbonyl group) is #1
How do you form a ring for carbons?
A covalent bond forms between the hydroxyl group on the 4th carbon and the carbonyl group on the first carbon. Because nucleotides are complex, sugar carbons are noted with a ‘ (prime). This differentiated the carbons of the sugar from the carbons in the nitrogenous base
What is a nucleoside?
Sugar+base=nucleoside
A dehydration reaction between the nitrogenous base and the 1’ C of the pentose links the base to the sugar
What is the phosphate group?
Inorganic phosphate can form a covalent bond with the 5’ carbon of the nucleoside by a dehydration reaction
What can a phosphate group make on a nucleoside?
Nucleotide (monomer of DNA and RNA)
What are polynucleotides?
Dehydration reaction between:
The phosphate group on one nucleotide
The hydroxyl on the 3’ carbon of a second nucleotide
These link monomers together
How does DNA usually exist?
As two strands of polynucleotides
What are complementary bases in the DNA structure?
Pair between the two strands
What is the double helix in the DNA structure?
Two strands form a double helix
What is anti-parallel in DNA structure?
The strands run in opposite 5’ to 3’ directions
What does RNA usually exist as?
RNA usually exists as a single polynucleotides strand
What are other aspects of the RNA structure?
Bases in one part of the strand can hydrogen bond to complimentary bases in another part of the strand. Can create complex structures
What is the difference between the genetic materials of DNA and RNA?
DNA
double stranded
Only found in the nucleus
Contains A,G, C, and T
Sugar= deoxyribose
RNA
Single stranded
Found both inside and outside of the nucleus (cytoplasm)
Contains A,G, C, and U
Sugar= ribose
What is DNA replication in short?
DNA makes a copy of itself for cell division (nucleus)
What is DNA transcription in short?
DNA creates messenger RNA (nucleus)
What is RNA translation in short?
RNA is translated to produce a protein (cytoplasm)
