long polymers (thousands) of nucleotides therefore, sometimes called polynucleotides each nucleotide...
TRANSCRIPT
Nucleic Acids B.8
Structure of DNA/RNA (B.8.1-3)
long polymers (thousands) of nucleotidestherefore, sometimes called polynucleotides
each nucleotide consists of 3 parts1. a phosphate group2. a pentose sugar called deoxyribose in DNA (or
ribose in RNA)3. in DNA/RNA, five nitrogen bases (only need to
recognize these)DNA - thymine(T), cytosine(C), adenine(A) and guanine(G)RNA – uracil(U) is substituted for thymine
Warning: Lots of pictures of nucleotides
DNARNA
Condensation reactionthe joining of nucleotides with a phosphodiester bond (a covalent bond) to form a sugar-phosphate backbone
RNA DNAsugar is ribose (OH is on 2’ carbon)
sugar is deoxyribose (H is on 2’ carbon)
contains the base uracil
contains the base thymine
single stranded two strands forming a double helix held together by hydrogen bonds
Distinguish between RNA and DNA
complementary base pairingthe size and shape of the bases is such that hydrogen bonds can only form at specific sitesadenine only forms two hydrogen bonds with thymineguanine only forms three hydrogen bonds with cytosine
why twisting/spiraling of DNA?it minimizes the repulsion between negatively charged phosphates
DNA as information (B.8.4)
inherit genetic material from parentsgenetic info. on DNA allows proteins to be made through the process of transcription and translation
Replicationhttp://highered.mcgraw-hill.com/sites/0072437316/student_view0/
chapter14/animations.html
http://www.johnkyrk.com/DNAreplication.html
Transcription and Translation
http://highered.mcgraw-
hill.com/sites/0072437316/
student_view0/chapter15/
animations.html
64 codons that code for 20 amino acids or to stop
DNA profiling steps and uses (B.8.5)
commonly known as ‘DNA fingerprinting’method used to identify individuals by similarities or differences in their DNA
isolation of the DNA from a sample sourceblood, semen, skin cells, hair or saliva
DNA is the cut up with restriction enzymes and replicated
these DNA fragments are then separated into bands according to size using gel electrophoresis
the resulting pattern is transferred to a nylon membrane, labeled with radioactive 32P, and exposed to x-ray filmfilm is finally compared to other samples of DNA