3.5- Nucleic Acids Flashcards
What do nucleic acids contain?
elements
phosphorous, C, N ,H, O
DNA-
instructions for synthesis of proteins by making the sequences of a.a in polypeptides through transcription and translation
What are nucleic acids made up of?
nucelotides
pentose sugar (deoxyribose & ribose)
a nitrogenous base ( adenine, cytosine, guanine, thymine or uracil) and phosphate group
what is the function of RNA
involved in protein synthesis
chromatin
DNA and histoen protein
What are pyrimidines?
single ring carbon structures; cytoseine thymine/ uracil
What are purines?
2 carbon nitrogen rings
adenine, guanine
phosphodiester linkage:
Covalent bond; found in nucleotides
DNA Backbone & interior consists
sugar and phosphate= phosphodiester bonds
nitrogenous base- interior = hydrogen bonds
Ribonuceloutides bonds?
phosphodiester bonds
mRNA
synthesizes protein and communicates the message. RNA base sequence complementary to DNA- codons (sets of 3)- single a.a.
rRNA
major constitient of ribosomes
ensures alignment of mRNA & ribosomes
has enzymatic activity ( pedptidyl transferase0 7 catalyzes formation of peptide bonds
tRNA
carries correct a.a. for protein synthesis; base paring b/w tRNA & RHA for correct a.a.
microRNA
smallest; involves the regulation of gene expression by interfering w/ the expression of mRNA message
Describe the central dogma of life
Transcription- DNA dictates structure of mRNA
Translation RNA- dictates structure of protein
