CBIO 2200 1nd Edition Lecture 5 Outline of Last Lecture I Lipids II Proteins III ATP Other Nucleotides and Nucleic Acids IV Cell Shapes and Sizes V Membrane Transport Outline of Current Lecture I Processes of membrane transport II Vesicular Transport III The Cell Interior Chapter 5 Histology IV Introduction to Ch 5 Current Lecture I Processes of membrane transport a Three processes that employ a transport protein or carrier i Facilitated diffusion passive need some type of assistance ii Primary active transport requires ATP iii Secondary active transport requires ATP b Carrier mediated transport i Facilitated diffusion transport of solute through a membrane down its concentration gradient 1 Does not consume ATP These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute II 2 One a solute binds to the receptor on the carrier the carrier changes shape and transports it to other side of membrane ii Primary active transport transport of solute through a membrane against its concentration gradient 1 ATP energy consumed to change carrier shape 2 Examples sodium potassium pump iii Secondary active transport 1 Sodium glucose transporter the transport is active but does not in and of itself require energy it is active because another pump that does require energy is active a When sodium is high on outside of cell sodium glucose transport is active glucose piggybacks on sodium into the cell b For this to be active the sodium potassium must be active also c Indirect requirement of ATP 2 The glucose goes down its concentration gradient c Characteristics of carriers i Specificity transport proteins are specific for a certain ligand molecule ii Saturations transport maximum Tm once all binding sites are filled they can t carry any more d Uniport transporter only carries one solute at a time in one direction e Symport transporter can carry two or more solutes at the same time ex sodium glucose transporter f Antiport transport carries two solutes at the same time but in different directions counter transport ex sodium potassium pump Vesicular transport moving large particles fluid droplets or numerous molecules through the membrane in vesicles a Endocytosis vesicular processes that bring material into cell i Phagocytosis cell eating cell membrane envelopes the particle and takes it into the cell ii Pinocytosis cell drinking taking in droplets of extracellular fluid vesicle taken in with fluid inside called a pinocytotic vesicle vesicle is then broken down inside cell iii Receptor mediated endocytosis particles specific molecule bind to specific receptors on plasma membrane very specific molecule binds to a very specific receptor and then the cell membrane invaginates the molecules the site that takes in the molecules is coated by a protein call clatherin which tells the cell it needs to invaginate the molecules b Exocytosis discharging material from the cell i Secreting material III ii A secretory vesicles containing things the cell need to get rid of approaches the plasma membrane the vesicle and membrane fuse and release molecules c All Vesicular transport utilizes proteins that require ATP The Cell Interior a Organelles i Internal structures carry out specialized metabolic tasks ii Membranous organelles surrounded by membrane Ex nucleus mitochondria endoplasmic reticulum iii Non membranous organelles not surrounded by membrane Ex centrosomes centrioles ribosomes iv Nucleus largest organelle five micrometers in diameter 1 Nuclear envelope two unit membranes surround nucleus 2 Nucleoplasm material inside the nucleus a Chromatin DNA and protein b Nucleoli regions where you find ribosomes that are involved in protein synthesis v Endoplasmic reticulum ER system of interconnected channels called cisternae 1 Rough ER ribosomes attached to it a Involved in protein synthesis 2 Smooth ER lack ribosomes a Participates in production of lipids and detoxification of drugs i e alcohol vi Ribosomes granules of protein and RNA 1 They read messenger RNA and assemble amino acids into proteins vii Golgi complex cisternae membranous 1 Participates in synthesis of carbohydrates that are added to proteins viii Lysosomes packages of enzymes 1 Functions a Intracellular hydrolytic digestion b Autophagy digest and dispose of worn out organelles c Autolysis cell suicide happens when a whole cell wears out each cell has a lifetime i Also called apoptosis programmed cell death ix Peroxisomes resemble lysosomes but contain different enzymes and are not produced by the golgi complex they are produced by ER 1 General function is to use molecular oxygen to oxidize organic molecules 2 Enzyme found in peroxisome called catalase breaks down hydrogen peroxide that is produced in metabolism a H2O2 H2O O2 x Proteosomes 1 Hollow cylindrical organelle that breaks down proteins that are not made correctly or any protein that has gone through its lifespan xi Mitochondria organelle specialized for synthesis of ATP 1 Power house of the cell 2 Energy is extracted from organic molecules and transferred to ATP xii Centrioles 1 Made up of microtubules arranged in nine groups of three microtubules each 2 Play a role in cell division because they set up microtubule organizing center 3 Form basil bodies of cilia and flagella b Cytoskeleton i Skeleton made of proteins that gives cell shape and structural support called filaments ii Helps direct proteins as they move throughout cell railroad of cell iii Collection of filaments and cylinders iv Composed of 1 Microfilaments 2 Intermediate fibers 3 Microtubules c Inclusions i Two kinds of inclusions 1 Stored cellular products a Fat droplets glycogen granules and pigments 2 Foreign bodies a Viruses bacteria dust other materials phagocytized by cell d All embedded in a clear gelatinous cytosol CHAPTER 5 not on first test 50 trillion cells 200 different types IV Introduction a Four broad categories of tissues i Epithelial tissue ii Connective tissue iii Nervous tissue iv Muscular tissue b Histology microscopic anatomy of the cells in these tissue categories V Epithelial tissue a Covers body surface and lines body cavities inner and outer surfaces b Can be thin or very thick 1 or more layer of cells c Basement membrane cells rest upon this it separates epithelium from connective tissue d Surfaces of epithelial cells i Basal surface cells resting on basement membrane ii Apical surface faces away from basement