DNA, RNA, Transcription, and Translation
• Chapter 12.3 DNA Replication pg. 350
• DNA carries the info to make Proteins. How does it work?
DNA Review
Segments of DNA (GENES) are the instructions
that control the production of proteins.
Genetic messages can be decoded by copying part of the nucleotide sequence from
DNA into RNA.
RNA contains coded information for making proteins
How does the DNA get made into RNA and that made into Protein?
Transcription
• Double stranded DNA must be transcribed
• After being transcribed it will create single-stranded RNA
Remember the composition of DNA and RNA
DNA
1. The sugar = deoxyribose
2. The bases = A, C, G, T
3. It is a double strand
4. Remains in the nucleus of
the cell
Remember the composition of DNA and RNA
RNA
1.
The sugar = ribose
2.
The bases = A, C, G,U
3.
It is a single strand
4.
RNA will leave the
nucleus
Types of RNA
• mRNA = Messenger RNA
• made from DNA in nucleus…travels out of nucleus and finds a ribosome.
• tRNA = Transfer RNA
• brings amino acids to the ribosomes; found in cytoplasm
• rRNA = Ribosomal RNA
• part of the ribosome; this is where proteins are made
mRNA
• Carries the copies of instructions in order to determine how
amino acids will be assembled into proteins
Ribosomes and rRNA
• Ribosomes are made up of proteins and ribosomal RNA (rRNA).
tRNA
• During protein construction, transfer RNA (tRNA)
transfers each amino acid to the ribosome.
Transcription
• RNA molecules are produced by copying part of a nucleotide
sequence of DNA into a complementary sequence in RNA. This
process is called transcription.
• Transcription requires the enzyme RNA polymerase.
Codons Video
• https://www.youtube.com/watch?v=XwTExa8rs5A
Translation
• The mRNA codes for certain amino acids
• Strings of amino acids are proteins.