BIOL 1140 1st Edition Lecture 6Outline of Last LectureI. LipidsII. ProteinsIII. Nucleic AcidsIV. ATPOutline of Current Lecture I. Basic Cell TypesII. Cell structure and functionIII. Plasma MembraneIV. Membrane TransportV. Passive TransportVI. Active TransportVII. Endocytosis and Exocytosis VIII. Cell OrganellesIX. Cellular RespirationCurrent LectureI. Two basic cell typesa. Prokaryotei. No nucleusii. No membrane-bound organellesiii. Cell membrane plus cell walliv. smallerb. Eukaryotei. Nucleus: compartment containing DNAii. Organelles (structures with specialized functions)iii. Cell membraneiv. Largerv. All human cells are thisThese 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. Cell structure reflects sell functiona. All eukaryote cells have same features but serve different functionsi. Muscle cells1. Contain more mitochondriaii. Nerve cells1. Long and thin to carry nerves over distanceiii. All very small, because...b. Cells need to…i. Import nutrients and oxygenii. Export products made in the celliii. Dispose of waste c. All cell traffic must move across the membraned. Small cells have higher surface area to volume ratioIII. The Plasma Membranea. Separates a cell from its environmentb. Selectively permeablei. Permits movement of some substances into and out of the cell but blocks othersc. Enables transfer of info between environment and celld. Composed mainly of a phospholipid bilayeri. 2 layers of phospholipidsii. Polar, hydrophilic phosphate 'heads' on outsideiii. Nonpolar, hydrophobic fatty acid 'tails' on insidee. Components of plasma membranei. Phospholipids: hydrophobic interior is a barrier to most molecules ii. Cholesterol: makes membrane more rigidiii. Proteins: provide transport channels through membrane; receptors for signaling molecules iv. Carbohydrates: recognition molecules for cells and organismsIV. Membrane Transporta. Cells use different methods to move substances in and out of cell, depending on size and charge of the substanceb. Passive transport no energy neededi. Diffusion, facilitation diffusionii. Osmosisc. Selectively permeable membranei. Membrane interior is hydrophobicii. Hydrophobic and small molecules move across easilyV. Passive transporta. Movement occurs by diffusioni. Spontaneous movement of molecules from high concentration toward lower concentration1. Diffusion through phospholipid bilayera. Very small or nonpolar molecules (o2, CO2)b. Facilitated diffusioni. Used by larger or polar moleculesii. Movement through transport or carrier proteins in the membrane, down the concentration gradient, without energy use c. Osmosisi. Diffusion of waterii. Water moves toward a region with higher solute concentration VI. Active transporta. Moves substances from an area of lower concentration to and area of higher concentration i. Requires a membrane protein (transport channel)ii. Requires ATP or other energy source iii. Used by molecules of any size or charge if they’re moving up the concentration gradient VII. Endocytosis and exocytosisa. Used to move larger molecules, large quantities at once, or even whole cellsi. Endocytosis: brings substance into the cell using a vesicle (membrane-bound sac)ii. Exocytosis: expels substances from the cell when a vesicle fuses with the cell's membraneVIII. Cell Organellesa. Eukaryotic cells contain many organelles that perform specific functions for the cellb. KNOW ORGANELLE FUNCTIONS. ON EXAM, AS WELL AS LAB QUIZ….only discussed inlab/lab manual. Not lecture IX. Cellular Respirationa. Food we eat is digested into subunits, which are then absorbed into our bloodstreamand delivered to cells b. Cells cant directly use stored energy in food- they need ATP energy c. Respiration is the process of manufacturing ATP from the energy stored In glucosed. Also called aerobic respiration- uses oxygen e. In absence of glucose, other carbohydrates, fats, and protein can be used to make ATPf. Summary chemical equationi. Glucose is broken down, oxygen and ADP are used up 1. ADP- Adenosine di-phosphate2. Carbon dioxide and water (waste products) and ATP energy are
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