Nucleic Acids and DNA Flashcards
What are the three components of a nucleotide?
1) Phosphate Group
2) a sugar
3) a nitrogenous base
purines
A class of small, nitrogen-containing, double-ringed bases (guanine, adenine) found in nucleotides.
pyrimidines
A class of small, nitrogen-containing, single-ringed bases (cytosine, uracil, thymine) found in nucleotides.
What is the difference in structure of the ribonucleotides and deoxyribosenucleotides?
Deoxyribonucleotides have the pyramidine uracil instead of thymine
phosphodiester linkage
Chemical linkage between adjacent nucleotide residues in DNA and RNA. Forms when the phosphate group of one nucleotide condenses with the hydroxyl group on the sugar of another nucleotide. Also known as phosphodiester bond.
ribonucleic acid
A nucleic acid composed of ribonucleotides that usually is single stranded and functions as structural components of ribosomes (rRNA), transporters of amino acids (tRNA), and translators of the message of the DNA code (mRNA).
deoxyribonucleic acid
A nucleic acid composed of deoxyribonucleotides that carries the genetic information of a cell. Generally occurs as two intertwined strands, but these can be separated
nucleic acid chains start at _ and end at _
5’ and 3’ of a sugar base
nucleotides are added to what part of another nucleotide?
3’ of the sugar base
What forms the primary structure of a nucleic acid?
The sequence of nitrogenous bases
What forms the secondary structure of nucleic acids?
Hydrogen bonding between nitrogenous bases
The number of _ is equal to _ and the number of _ and _are equal and _ _ are equal in DNA
pyramidines, purines, A, T, G, C
antiparallel
Describing the opposite orientation of the strands in a DNA double helix with one strand running in the 5¢ ® 3¢ direction and the other in the 3¢ ® 5¢ direction.
What are the differences in structure of A-T pairing and G-C pairing?
A-T has two hydrogen bonds and G-C has three hydrogen bonds being more stable
complementary base pairing
The association between specific nitrogenous bases of nucleic acids stabilized by hydrogen bonding. Adenine pairs only with thymine (in DNA) or uracil (in RNA), and guanine pairs only with cytosine.
Watson-Crick pairing
same as complementary pairing
What are DNA’s properties in relation to water?
inside is hydrophobic due to bonding of the nitrogenous bases and outside is hydrophyllic due to sugar-phospate backbone
Why is DNA antiparallel?
purine and pyramidine bonding, purines only match with pyramidines. Purines contain two molecule while pyramidines only one.
template strand
(1) The strand of DNA that is transcribed by RNA polymerase to create RNA. (2) An original strand of RNA used to make a complementary strand of RNA.
complementary strand
A newly synthesized strand of RNA or DNA that has a base sequence complementary to that of the template strand.
look at proteins and DNA in class slide
Looked at!
