AS - CH 6 Nucleic Acid & Protein Synthesis PDF

AS - CH 6 Nucleic acid & Protein synthesis  Learning outcomes Describe structure of Describe purines and 01 nucleotides 02 pyrimidines Describe structure of 03 DNA molecule as...

AS - CH 6 Nucleic acid & Protein synthesis  Learning outcomes Describe structure of Describe purines and 01 nucleotides 02 pyrimidines Describe structure of 03 DNA molecule as double helix Nucleotides, building blocks of nucleic acids Link together forming long chains, creating; DNA, two chains twist together forming double helix RNA, single chain that helps with biological roles  Parts of Nucleotides Phosphate group Pentose sugar Nitrogenous Phosphorus and oxygen DNA; deoxyribose base Adenin, Thymine, RNA; ribose Cytosine, Guanine, Uracil DNA & RNA Nucleotides Difference 5 5 4 1 4 1 3 2 3 2 OH OH OH DNA RNA 2-deoxyribose Ribose  Nitrogenous base RNA DNA Larger double-ring structures Smaller single-ring structures 6 + 5 membered rings 6 membered ring  Who am i? 5 4 1 3 2 Nitrogenous bases pairs DNA RNA 5’ to 3’ in DNA  DNA double helix A T G C Double helix C G DNA double helix New nucleotides are always added in a 5’ to 3’ direction  Conclusion Nucleotides Consist of 3 parts ○ Phosphate, sugar, base Purines (A & G) have larger structure compared to pyrimidines (C, U, T) DNA structures Made out of DNA nucleotides joined together by phosphodiester bonds 2 strands are antiparallel, they are connected by hydrogen bonds via complementary base pairing 2 strands coil around each other forming a double helix  Learning outcomes Describe leading and Role of DNA 04 polymerase & ligase 05 lagging strand 06 Structure of RNA  DNA replication The process of making identical copy of DNA molecule To prepare the cell for S phase during mitosis/ meiosis (will be discussed in ch 16) ‘S’ phase, DNA replication occurs (amount of DNA doubles)  Principle of DNA replication Models for new strands Hydrogen Unwinds bonds break 1 original DNA The original molecule (template) strands separate  Free nucleotides Semi-conservative replication 2 new identical DNA molecules Form complementary Formation of base pairing phosphodiester bond  DNA replication (Unwind) Helicase enzyme, unwinds the DNA exposing the base of the template strands Hydrogen bonds break  DNA replication (DNA Polymerase) DNA polymerase, an enzyme that form the new strand (aid in the formation of phosphodiester bonds) Synthesis new DNA; add nucleotides to the growing DNA strand in 5’ to 3’ direction. Proofreading; check and corrects error during DNA synthesis DNA polymerase Leading strand Lagging strand Replication fork  DNA replication (Ligase) Ligase, Join okazaki fragments on the lagging strand creating continuous DNA strand Leading strand; synthesized continuously in the 5’ to 3’ direction Lagging strand; synthesized discontinuously, creating short fragments (okazaki fragments).  RNA Single-stranded nucleic adi Made up of RNA nucleotides joined by phosphodiester bonds 3 types of RNAs; ○ Ribosome RNA (rRNA) ○ Messenger RNA (mRNA) ○ Transfer RNA (tRNA) Messenger RNA Transfer RNA Ribosome RNA (mRNA) (tRNA) (rRNA) Every triplet (3) Can fold within bases are referred itself (forming to as 1 codon hydrogen bonds) Only has 1 anticodon 3’ end attached to rRNA will coil within specific amino themselves acid Forming a ribosome when added protein CCA  Conclusion Purpose of DNA replication; ensure each new cell has an identical copy of DNA. Location; in the nucleus of eukaryotic cells. Semi-conservative; new DNA molecule consists of one original strand and one newly synthesized strands. Key enzyme; Helicase DNA polymerase Ligase  Learning outcomes Describe how Explain how mRNA information in DNA is 08 used (translation & 10 was formed in eukaryotes transcription) Describe transcribed Describe gene 09 & non-transcribed strand 11 mutation  Protein synthesis Cells build proteins based on genetic instruction from DNA Protein synthesis is the process where cells generate new proteins, that are essential for the structure, function, and regulation of the body’s tissues and organs. There are 2 main stages of protein synthesis; ○ Transcription ○ Translation  Protein Synthesis Transcription Translation Nucleus ( eukaryotic) Ribosome (cytoplasm) Initiation; RNA binds to the promoter region of a Initiation; Ribosome assembles around the first gene on the DNA strand. tRNA, which has start codon. Elongation; RNA polymerase unzip DNA & Elongation; tRNAs bring amino acids based on synthesize complementary strand of mRNA by codons in mRNA. Forms peptide bonds between adding RNA nucleotides based on DNA template amino acids, creating a polypeptide chain. Termination; RNA polymerase reaches Termination; continues until stop codon (UAA, termination signal & releases newly formed UAG, or UGA). The newly formed polypeptide mRNA strand chain is released. mRNA that has genetic code from DNA for A polypeptide chain that will fold into a protein synthesis functional protein.  Protein synthesis tRNA Inside nucleus In Cytoplasm Gene Protein Ribosome  Transcription Inside the nucleus RNA nucleotides Non-template strand RNA nucleotides form complementary DNA reforms and base pairings with wind back together Gene the template strand Only the gene umwinds RNA polymerase Template strand Forms phosphodiester mRNA bonds between RNA nucleotides  Translation In the cytoplasm (by ribosome) tRNA Inside ucleus In Cytoplasm tRNA carry amino acids to the ribosome Anticodons & codons form complementary base pairing Ribosome mRNA binds to the small subunit Ribosome will link 2 amino acids Codons are exposed to the large together with peptide bond subunit  Gene mutation Random change in the base sequence of the gene/ DNA Error during DNA replication Many of this planet’s craters were named after artists or authors who made significant contributions to their respective fields. Mercury takes a little more than 58 days to complete its rotation, so try to imagine how long days must be there! Since the temperatures are so extreme, Damage due to mutagens albeit not as extreme as on Venus, and the solar radiation is so high  Thanks! CREDITS: This presentation template was created by Slidesgo, and includes icons by Flaticon, and infographics & images by Freepik