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Problem. DNA is in the nucleus…… Proteins are made on the ribosomes in the cytoplasm…… How does the information get from the DNA in the nucleus to the ribosomes in the cytoplasm?. RNA. Chapter 10-2. DNA Deoxyribonuleic acid Sugar is deoxyribose N base: A, C, G, T Double stranded
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Problem • DNA is in the nucleus…… • Proteins are made on the ribosomes in the cytoplasm…… • How does the information get from the DNA in the nucleus to the ribosomes in the cytoplasm?
RNA Chapter 10-2
DNA Deoxyribonuleic acid Sugar is deoxyribose N base: A, C, G, T Double stranded Contains information about cell activities, cell division, and the code to make proteins Stays in the nucleus RNA Ribonucleic acid Sugar is ribose N base: A, C, G, U Single stranded Reads the information carried by DNA Transfers information on making proteins Leaves the nucleus 3 types: mRNA, tRNA, rRNA DNA & RNA are both Nucleic Acids
RNA types • Messenger RNA (mRNA): carries information from DNA in the nucleus to the ribosomes in the cytoplasm • Transfer RNA (tRNA): reads the mRNA and brings the proper amino acid to the ribosome (contains an anti-codon on one end and an amino acid on the other) • Ribosomal RNA (rRNA): component of the ribosomes
Takes place in the nucleus of the cell The process where genetic information from DNA is “downloaded” to messenger RNA Transcription
Transcription • Works just like DNA replication, but produces only one strand of mRNA • The DNA is unzipped by the enzyme “Helicase” • Starts at the promoter and goes to the terminator • The enzyme “RNA Polymerase” reads the DNA and pairs complimentary RNA nucleotides to the RNA strand • The mRNA leaves the nucleus • DNA zips back up
The strand of mRNA is complimentary because it is constructed from the DNA nucleotide sequence! • Remember: Uracil replaces Thymine in the mRNA sequence
Transcription Animation http://www.johnkyrk.com/DNAtranscription.html
Practice • If the DNA strand is AACT, what would the newly synthesized RNA strand be?