What are nucleic acids? What do they do?
Responsible for storage and processing of cell info
-strucutre of every protein is encoded by nucleotide sequence
2 types: DNA and RNA
What is specific to DNA? What is specific to RNA?
DNA: directs cell function, stores genetic info, found only in nucleus of eukaryotes
-uses sugar deoxyribose
RNA:used info stored in DNA to synthesize proteins and other RNAs. Found
throughout cell.
-uses ribose as sugar
-3 different types
--mRNA: carries DNA info from the nucleus to ribosomes where protein synthesis
occurs.
--tRNA: brings specific amino acids to the ribosomes
--rRNA: helps form structure of ribosomes.
Compare and contrast nucleic acids and proteins.
Proteins are single stranded polymers made of 20 amino acids. The primary
structure of a protein is the amino acid sequence. Alpha-helices and Beta-sheets are
protein secondary structure.
Nucleic acids are single-stranded polymers made of 4 nucleotides. The primary
structure of the nucleic acid is the nucleotide sequence. The double helix is a nucleic
acid secondary structure.
What does a nucleotide consist of? Draw it out and label.
H2
C
O
O
P
O
H2 C
–
O
–
H2 C
CH2
O
HC
H2 C
Phosphate
CH2
Base
Base
CH2
CH
CH
CH2
did not put OH's and H's on sugar ring
Remember, they are there.
Sugar
What are the 5 bases? Which bases are the purines and which are the pyrimidines?
Cytosine, Uracil and thymine=pyrimidines (CUT the PY)
Adenine and Guanine=purines
What is a nucleoside? Draw one and label bonds.
H2
C
H2 C
CH2
H2 C
CH3
O
HC
CH2
Base
H2 C
CH
N-glycosidic bond
CH
CH2
did not put OH's and H's on sugar ring
Remember, they are there.
Sugar
Draw a dinucleotide composed of cytosine and adenine (DNA).
NH2
HC
N
Cytosine
O
O
–
P
O
HC
CH2
O
HC
O
–
HC
N
O
CH
CH2
NH2
O
O
–
N
P
O
O
CH2
HC
N
N
O
HC
CH
HC
OH
CH2
N
CH
Adenine