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
What are the differences in the structure of RNA and DNA (3)?
- DNA- deoxyribose sugar
RNA- ribose sugar - DNA- one less oxygen
RNA- extra oxygen - DNA- double stranded
RNA- single stranded
How many hydrogen bonds are there between A and T?
Double Bond
How many hydrogen bonds between C and G?
Triple Bond
Define Antiparallel
The two DNA strands run parallel to each other however they run in opposite directions
5’ and 3’ end of DNA
the 5’ end of the DNA is parallel to the 3’ end of the DNA
What are the nitrogenous base pairs?
Adenine with Thymine/Uracil
Cytoseine and Guanine
