Biology Exam 4
Card Set Information
Biology Exam 4
What do nucleotides consist of?
4 base pairs of DNA
Thymine, Cytosine= pyridamines
5', 3' rule
3rd and 5th carbons of sugar are places where nucleotides attach. Always goes 5 touching 3, not 3 touching 5.
What kinds of bonds hold nitrogenous bases together?
Mnemonic for nitrogen base pairs
Two scientist that put together the first model of DNA
Watson and Crick
when DNA replicates and leaves one original strand to build a new strand.
1) Helicase proteins unwind DNA
2) Binding proteins keep DNA apart
3) Primase makes complementary RNA
4) DNA Polymerase adds complementary DNA nucleotides and proofreads
5) Exonuclease removes RNA primers
6) Ligase fills in gaps and seals strands
replication is fast and smooth because it's going 5' ---> 3'
replication uses Okizaki fragments because it's going 3' ---> 5'
mutation in helicase, advanced aging
-RNA is ___________ nucleic acid composed of RNA nucleotides:
-RNA utilizes ________ sugar
-RNA nucleotides use four bases:
______, Adenine, Cytosine, and Guainine
Single-stranded; ribose; Uracil
transcribed message from DNA
structure where translation occurs
transfers amino acids according to the mRNA message
adds in complementary RNA nucleotides to match the DNA template and proofreads
non-coding sequence in RNA processing
coding sequences in RNA processing
quality control before RNA leaves nucleus
1) add cap
2) add tail
3) cut out introns and paste in extrons
How many base pairs is mRNA read as?
3 nucleotides/base pairs (codons) that code for 1 amino acid
How many codons can an amino acid have?
more than 1! NOT THE OTHER WAY AROUND
recognizes mRNA message
made of rRNA and protein
change in DNA sequence
base pair substitution (1 for 1 switch)
codes for same amino acid
code for premature stop
code for incorrect amino acid
adding or deleting a base
-1 in 1bil.
-DNA polymerase proofreads
environmental factors for mutation
UV light, carcinogens