Cell Biology BE 307 Izmir Institute of Technology PDF

10/7/24 Cell Biology BE 307 Assoc. Prof. Dr. Ahu ARSLAN YILDIZ Izmir Institute of Technology 07/10/2024 Tentative Course Flow...

10/7/24 Cell Biology BE 307 Assoc. Prof. Dr. Ahu ARSLAN YILDIZ Izmir Institute of Technology 07/10/2024 Tentative Course Flow 1  10/7/24 Text books / Grading & Exams Introduction to Cells & Cell Research Cell Biology ; the study of the structure, function and behavior of cells Complex Biological Atom Molecule Macromolecules Architectures Cells Organelles BE 307 Cell Biology Ahu ARSLAN YILDIZ 2  10/7/24 Diversity of Living Organisms When we look at the living organisms on earth, we see tremendous amount of them. In the first chapter, we will highlight both unity/similarities and the diversity of cells. All living things share the same machinery for their most basic functions. BE 307 Cell Biology Ahu ARSLAN YILDIZ The Universal Features of Cells The fundamental similarities between different types of cells provide a unifying concept to cell biology. It is estimated that there are more than 10 million – perhaps 100 million – living species on Earth today. The parent organism hands down the genetic information to the offspring and this phenomenon is called as “heredity”. Heredity is the central to the definition of life. BE 307 Cell Biology Ahu ARSLAN YILDIZ 3  10/7/24 The Universal Features of Cells A single cell ; fertilized egg cell is a vehicle for all hereditary information. Each species is able to reproduce; transmission of hereditary information to the progenies. Only living things are able to produce progenies that resemble their parent. Sea Urchin Mouse Seaweed BE 307 Cell Biology Ahu ARSLAN YILDIZ The Universal Features of Cells 1. All Cells Store Their Hereditary Information in the Same Linear Chemical Code: DNA All living cells on Earth store their hereditary information in the form of double- stranded molecules of DNA A piece of DNA from an organism can be read by the another one. It is an universal alphabet. BE 307 Cell Biology Ahu ARSLAN YILDIZ 4  10/7/24 The Universal Features of Cells 1. All Cells Store Their Hereditary Information in the Same Linear Chemical Code: DNA DNA is formed by monomers, known as nucleotides; represented by four letter - A, T, C, G. Each nucleotide, consists of two parts: a sugar (deoxyribose) with a phosphate group attached to it, and a base. BE 307 Cell Biology Ahu ARSLAN YILDIZ The Universal Features of Cells 2. All Cells Replicate Their Hereditary Information by Templated Polymerization In the living cell, DNA is not synthesized as a free strand, but on a template formed by a preexisting DNA. The DNA polymer is extended by adding monomers at one end; it is so called “templated polymerization” DNA Replication BE 307 Cell Biology Ahu ARSLAN YILDIZ 5  10/7/24 The Universal Features of Cells 3. All Cells Transcribe Portions of Their Hereditary Information into the Same Intermediary Form: RNA To carry out its function, DNA must do more than copy itself. It must also express its information for the synthesis of other molecules. This expression occurs by production of two other key molecules: RNAs and proteins. BE 307 Cell Biology Ahu ARSLAN YILDIZ The Universal Features of Cells 3. All Cells Transcribe Portions of Their Hereditary Information into the Same Intermediary Form: RNA The process begins with “Replication” Transcription: DNA act as a template for mRNA (Messenger RNA) synthesis. Translation: RNA molecules direct the synthesis of the proteins. BE 307 Cell Biology Ahu ARSLAN YILDIZ 6  10/7/24 The Universal Features of Cells 4. All Cells Use Proteins as Catalysts Protein molecules, like DNA and RNA molecules, are long unbranched polymer chains, formed by stringing together monomeric building blocks. Proteins has important function in the cell, such as enzymes which catalyze reactions. In this way they direct the many chemical processes in the cell. BE 307 Cell Biology Ahu ARSLAN YILDIZ The Universal Features of Cells 4. All Cells Use Proteins as Catalysts The monomers of protein, the amino acids , are quite different from those of DNA and RNA, and there are 20 types instead of 4. Each of the protein molecules is formed by a polypeptide chain. Each protein molecule performing a specific function according to its sequence of amino acids. BE 307 Cell Biology Ahu ARSLAN YILDIZ 7  10/7/24 The Universal Features of Cells 5. All Cells Translate RNA into Protein in the Same Way 6. Each Protein Is Encoded by a Specific Gene 7. Life Requires Free Energy 8. All Cells Function as Biochemical Factories Dealing with the Same Basic Molecular Building Blocks 9. All Cells Are Enclosed in a Plasma Membrane Across Which Nutrients and Waste Materials Must Pass BE 307 Cell Biology Ahu ARSLAN YILDIZ The Universal Features of Cells 5. All Cells Translate RNA into Protein in the Same Way 6. Each Protein Is Encoded by a Specific Gene 7. Life Requires Free Energy 8. All Cells Function as Biochemical Factories Dealing with the Same Basic Molecular Building Blocks 9. All Cells Are Enclosed in a Plasma Membrane Across Which Nutrients and Waste Materials Must Pass BE 307 Cell Biology Ahu ARSLAN YILDIZ 8  10/7/24 The Universal Features of Cells In the 1950s, the structure of DNA was revealed, but understanding how it specifies protein production was a mystery. Translation of genetic information from the 4-letter nucleotide code to the 20-letter protein code is an intricate process. BE 307 Cell Biology Ahu ARSLAN YILDIZ The Universal Features of Cells Information in mRNA is read in triplets, or codons, each encoding a single amino acid in a protein. There are 64 possible codons from 4 nucleotides, but only 20 naturally occurring amino acids. Some codons correspond to the same amino acid due to this redundancy. BE 307 Cell Biology Ahu ARSLAN YILDIZ 9  10/7/24 The Universal Features of Cells Transfer RNAs (tRNAs) read the genetic code from mRNA. Each tRNA carries a specific amino acid and an anticodon that matches mRNA codons through base-pairing. Ribosomes facilitate the translation process. They enable tRNAs to convert mRNA into polypeptide chain. BE 307 Cell Biology Ahu ARSLAN YILDIZ The Universal Features of Cells 5. All Cells Translate RNA into Protein in the Same Way 6. Each Protein Is Encoded by a Specific Gene 7. Life Requires Free Energy 8. All Cells Function as Biochemical Factories Dealing with the Same Basic Molecular Building Blocks 9. All Cells Are Enclosed in a Plasma Membrane Across Which Nutrients and Waste Materials Must Pass BE 307 Cell Biology Ahu ARSLAN YILDIZ 10  10/7/24 The Universal Features of Cells 5. All Cells Translate RNA into Protein in the Same Way 6. Each Protein Is Encoded by a Specific Gene 7. Life Requires Free Energy 8. All Cells Function as Biochemical Factories Dealing with the Same Basic Molecular Building Blocks 9. All Cells Are Enclosed in a Plasma Membrane Across Which Nutrients and Waste Materials Must Pass BE 307 Cell Biology Ahu ARSLAN YILDIZ The Universal Features of Cells A living cell is a dynamic chemical system. It must take free energy and raw materials from environment to run the necessary reactions. When it stops, a cell decays toward chemical equilibrium and soon dies. Animal cells derive energy from chemical bonds in nutrient molecules, while plants use sunlight as an energy source. BE 307 Cell Biology Ahu ARSLAN YILDIZ 11  10/7/24 The Universal Features of Cells 5. All Cells Translate RNA into Protein in the Same Way 6. Each Protein Is Encoded by a Specific Gene 7. Life Requires Free Energy 8. All Cells Function as Biochemical Factories Dealing with the Same Basic Molecular Building Blocks 9. All Cells Are Enclosed in a Plasma Membrane Across Which Nutrients and Waste Materials Must Pass BE 307 Cell Biology Ahu ARSLAN YILDIZ The Universal Features of Cells All cells make DNA, RNA, and protein. All cells have to contain and manipulate a similar collection of small molecules, including simple sugars, nucleotides, and amino acids, as well as other substances that are universally required. BE 307 Cell Biology Ahu ARSLAN YILDIZ 12  10/7/24 The Universal Features of Cells 5. All Cells Translate RNA into Protein in the Same Way 6. Each Protein Is Encoded by a Specific Gene 7. Life Requires Free Energy 8. All Cells Function as Biochemical Factories Dealing with the Same Basic Molecular Building Blocks 9. All Cells Are Enclosed in a Plasma Membrane Across Which Nutrients and Waste Materials Must Pass BE 307 Cell Biology Ahu ARSLAN YILDIZ The Universal Features of Cells Without a plasma membrane, the cell could not maintain its integrity. Plasma membrane act as a selective barrier for cells which enables the cell to gather nutrients from its environment, while removing waste product from intracellular to intercellular microenvironment. Plasma membrane contain specialized proteins; so called membrane proteins that transport molecules across the membrane. BE 307 Cell Biology Ahu ARSLAN YILDIZ 13  10/7/24 The Universal Features of Cells Plasma membrane is formed by amphiphilic lipid molecules; consisting of one part is hydrophobic (water-insoluble) and another part that is hydrophilic (water-soluble). When such molecules are placed in water they forms self-assembled structures and aggregate spontaneously. BE 307 Cell Biology Ahu ARSLAN YILDIZ The Universal Features of Cells BE 307 Cell Biology Ahu ARSLAN YILDIZ 14 10/7/24 15