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Remember!. Genes are DNA sequences that actually code for proteins! We talked about how we inherit our genes from our moms & dads, but how are the genes actually expressed? Protein Synthesis!. Protein Synthesis. DNA RNA Proteins Protein Synthesis (making proteins from your genes)
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Remember! • Genes are DNA sequences that actually code for proteins! • We talked about how we inherit our genes from our moms & dads, but how are the genes actually expressed? Protein Synthesis!
Protein Synthesis DNA RNA Proteins • Protein Synthesis (making proteins from your genes) occurs in 2 steps: • Transcription • Translation
Transcription • The process in which the nucleotide sequence of DNA is copied (in the nucleus!) into a complementary sequence of RNA • DNA mRNA
Transcription – Step 1 • The enzyme RNA Polymerase binds to the DNA in the nucleus & breaks the hydrogen bonds between the 2 strands.
Transcription – Step 2 • Using 1 strand of DNA as a template, RNA Polymerase adds nucleotides 1 by 1 & forms the new mRNA strand.
Transcription • DNA is like the “master plan” & mRNA is like the “blueprint” • The master plan stays in the office (the nucleus!) & the blueprint can be taken to the construction site (the ribosome!).
Transcription – Step 3 • When transcription is complete, the mRNA leaves the nucleus through the nuclear pores & enters the cytoplasm of the cell.
What is the complementary mRNA strand made during transcription of this DNA sequence?ATGCGATCGAGCGAA UACGCUAGCUCGCUU