6- nucleic acids Flashcards
3 components making up nucleotide
- pentose sugar
- phosphate group
- nitrogenous base
how do nucleotides join together
- through condensation reactions, forming phosphodiester bonds between sugar+phosphate
purines (carbon ring number)
2 C rings
A+G
pyrimides
3 C rings
UCT
how many H bonds form between C+G in DNA
how many between A and U/T
3
2
structure of RNA
- single stranded, made of 1 polynucleotide molecule
- ribose sugar
diffs between RNA+DNA
- DNA longer than RNA
- DNA double stranded, RNA single
- DNA thymine, RNA uracil
- deoxyribose vs ribose
ATP made of
- adenine
- ribose
- phosphate
bodily uses of ATP
- movement
- AT
- synthesis molecules
secretion of substances
how does ATP activate other molecules
phosphorylating them (adding phosphate group)
Pi released from ATP hydrolysis can phosphorylate other compounds+make more reactive
ATP characteristics allowing it to be used as immediate energy source
- releases small amount of energy
- broken down in 1 step
- rapidly synthesised
- inorganic phosphate phosphorylate other compounds
- unstable bonds
- soluble
role of mRNA
carry genetic info from DNA to ribosomes for protein synth
structure of tRNA
single-stranded molecules folded into clover-leaf shape, held together by H bonds.
contain an anticodon+amino acid binding site
codon
3 bases on mRNA coding for amino acid
anticodon
3 bases at end of tRNA molecule
mRNA and tRNA sim:
- both single stranded
- both contain ribose, phosphate, nitrogenous bases
diff between mRNA and tRNA
mRNA linear, clover-leaf
longer
tRNA H bonds, mRNA doesn’t
has amino acid binding site, mRNA doesn’t
mRNA has codons, tRNA has anticodons
ribose and deoxyribose sugar difference
Ribose sugar has a hydroxyl (OH) group at position 2,
deoxyribose sugar has a hydrogen (H) atom at position 2.
translation
mRNA binds to the ribosome
tRNA enters the ribosome carrying a specific amino acid
hydrogen bonds form between the anticodon and the codon
peptide bond forms between adjacent amino acids
structural features of DNA making it stable
- phosphodiester bonds hold sugar-phosphate backbone
- helical coil strong protection
- complementary base pairing in antiparallel strands with H bonds holding 2 strands together
STOP codons:
UAG, UAA, and UGA
