5.8 RNA.ppt

RNA Lesson Objectives 5.8.1 Compare and contrast RNA and DNA Comparing RNA and DNA The sugar in RNA is ribose instead of deoxyribose. RNA is generally single-stranded, not double-stranded. RNA contains uracil in place of thymine. 5.7.2 Differentiate between the role of ea...

RNA Lesson Objectives 5.8.1 Compare and contrast RNA and DNA Comparing RNA and DNA The sugar in RNA is ribose instead of deoxyribose. RNA is generally single-stranded, not double-stranded. RNA contains uracil in place of thymine. 5.7.2 Differentiate between the role of each DNA and RNA in the cell DNA and RNA perform different functions in humans. DNA is responsible for storing and transferring genetic information. RNA directly codes for amino acids and acts as a messenger between DNA and ribosomes to make proteins. Without RNA, the instructions in DNA could not be used by cells. 5.7.3 Relate between the structure and the function of the types of RNA: mRNA, tRNA, rRNA Types of RNA The three main types of RNA are: Messenger RNA Ribosomal RNA Transfer RNA Messenger RNA  An mRNA molecule is a copy of the portion of DNA that will be used to make a protein.  After being made in the nucleus, mRNA travels to the cytoplasm, the site of protein synthesis. Ribosomal RNA  Protein synthesis occurs on ribosomes, which are made up of two subunits.  These subunits consist of several molecules of ribosomal RNA (rRNA) and as many as 80 different proteins. Transfer RNA During protein synthesis, transfer RNA molecules (tRNA) carry amino acids from the cytoplasm to the mRNA. Progress Check 5.7.4 Describe the role of RNA polymerase in the making of messenger RNA during the process transcription RNA Synthesis: Transcription ranscription process 5.7.4. Describe the role of RNA polymerase in the making of messenger RNA during the process transcription RNA Synthesis: Transcription In transcription, segments of DNA serve as templates to produce complementary mRNA molecules. 5.7.4. Describe the role of RNA polymerase in the making of messenger RNA during the process transcription RNA Synthesis: Transcription  Progress Check Drag the complementary strand of mRNA to show the product of transcription of the DNA strand.  RNA Synthesis: Promoters How does RNA polymerase know where to start and stop making a strand of RNA? RNA polymerase binds only to regions of DNA that have specific base sequences. These regions are called promoters. RNA Synthesis: Promoters RNA polymerase binds only to regions of DNA that have specific base sequences. These regions are called promoters.  5.7.5 Distinguish between introns and exons in RNA editing (processing) What happens to the newly made mRNA before it leaves the nucleus? 5.7.5 Distinguish between introns and exons in RNA editing (processing) RNA Synthesis: RNA Editing New RNA molecules sometimes require a bit of editing before they are ready to be read. Intron Exons s Cap Tai l