DNA Test

Determined the structure of DNA

Structure of DNA

4 nitrogenous bases

A pairs with __

C pairs with __

-Helicases unwind and unzip the DNA by breaking hydrogen bonds
-creates a replication fork

DNA Polymerase adds complimentary nucleotides to each of the original strands

-DNA polymerase leaves
-Result: two separate and identical DNA molecules that are semi-conservative

Semi-conservative means

Shape of RNA

In RNA, Thymine is changed to what nitrogenous base?

A ribosome attaches to the mRNA and starts to code for the nitrogenous bases

tRNA brings the corresponding amino acid to each codon as the ribosome moves down the mRNA strand.

Reading of the final mRNA codon (aka the STOP codon), which ends the sythesis of the peptide chain and releases it.

DNA ----> mRNA

mRNA ----> Protein

-ribosome attaches at start codon
-tRNA brings in methionine

-tRNA brings in amino acids to build polypeptide chain

-when stop codon is reached, ribosome detaches and polypeptide chain leaves

a change in any single nucleotide of a DNA sequence

the loss of one or more nucleotides in a DNA sequence

the addition of one or more extra nucleotides in a DNA sequence

Deletions and Insertions are categorized as ______ mutations

three possible results from a point mutation, deletion, or insertion occuring:

the mutation does not result in a change in the amino acid sequence

a mutation that causes one amino acid in the protein sequence to be changed to a different one

A mutation that results in a stop codon where there used to be a codon for an amino acid. This results in translation being stopped before the primary structure of the protein is complete