1. Lesson Overview Lesson OverviewFermentation Objectives 13.1 RNA -Contrast RNA and DNA. -Explain the process of transcription.

2. Lesson Overview Lesson OverviewFermentation What is RNA??? RNA, like DNA, is a nucleic acid that consists of a long chain of nucleotides. RNA stands for RiboNucleic Acid, while DNA stands for DeoxyriboNucleic Acid. RNA uses the base sequence copied from DNA to direct the production of proteins.

3. Lesson Overview Lesson OverviewFermentation Comparing RNA and DNA Each nucleotide in both DNA and RNA is made up of a 5- carbon sugar, a phosphate group, and a nitrogenous base. There are three important differences between RNA and DNA: (1) The sugar in RNA is ribose instead of deoxyribose. (2) RNA is generally single-stranded and not double- stranded. (3) RNA contains uracil in place of thymine.

4. Lesson Overview Lesson OverviewFermentation DNA vs RNA…

5. Lesson Overview Lesson OverviewFermentation Types of RNA The three main types of RNA are: 1. messenger RNA (mRNA) 2. ribosomal RNA (rRNA) 3. transfer RNA (tRNA).

6. Lesson Overview Lesson OverviewFermentation Messenger RNA (mRNA) The RNA that carries copies of the DNA instructions are known as messenger RNA (mRNA). They carry information from DNA to the ribosome.

7. Lesson Overview Lesson OverviewFermentation Ribosomal RNA (rRNA) Proteins are assembled on ribosomes. The ribosome is made up of several ribosomal RNA (rRNA) molecules and as many as 80 different proteins.

8. Lesson Overview Lesson OverviewFermentation Transfer RNA (tRNA) For a protein to be built, a transfer RNA (tRNA) molecule must transfer each amino acid to the ribosome by matching the mRNA’s CODON to the tRNA’s ANTICODON.

9. Lesson Overview Lesson OverviewFermentation Transcription Most of the work of making RNA takes place during transcription. During transcription, segments of DNA serve as templates to produce a complementary strand of RNA.

10. Lesson Overview Lesson OverviewFermentation Where does transcription take place? Prokaryotes - cytoplasm. Eukaryotes - nucleus and then protein synthesis happens on the ribosomes in the cytoplasm.

11. Lesson Overview Lesson OverviewFermentation RNA Editing RNA molecules sometimes require bits and pieces to be cut out of them. The portions that are cut out and discarded are called introns or “junk DNA”. The remaining pieces, known as exons, are then spliced back together to form the final mRNA.

12. Lesson Overview Lesson OverviewFermentation True or False 1.The three types of RNA are messenger RNA, transfer RNA, and ribosomal RNA. _________________________ 2.DNA molecules stay in the nucleus; RNA molecules leave the nucleus and move through the cytoplasm to the ribosomes. _________________________ 3.During DNA replication, only one strand of DNA serves as a template. _________________________

13. Lesson Overview Lesson OverviewFermentation Answers 1.The three types of RNA are messenger RNA, transfer RNA, and ribosomal RNA. true 2.DNA molecules stay in the nucleus; RNA molecules leave the nucleus and move through the cytoplasm to the ribosomes. true 3.During DNA replication, only one strand of DNA serves as a template. False, RNA replication