* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Cell Physiology
Survey
Document related concepts
Cellular differentiation wikipedia , lookup
SNARE (protein) wikipedia , lookup
Cytoplasmic streaming wikipedia , lookup
Cell encapsulation wikipedia , lookup
Magnesium transporter wikipedia , lookup
Implicit solvation wikipedia , lookup
Cytokinesis wikipedia , lookup
Membrane potential wikipedia , lookup
Signal transduction wikipedia , lookup
Organ-on-a-chip wikipedia , lookup
Cell membrane wikipedia , lookup
Transcript
Chapter 3 Cells Physiology Do you remember learning about? •Membrane Transport -Passive -Active Membrane Transport Movement into and out of cells to maintain HOMEOSTASIS Filtration Cellular Fluids Solution - Solvent – dissolving medium (ex. water) - Solutes – what gets dissolved (ex. sugar, salt) Intracellular fluid - inside cell Interstitial fluid - outside cell Passive Processes Diffusion Molecules ALWAYS moving; Brownian motion Movement from high to low concentration, or down a concentration gradient Equilibrium - concentration is equal/balanced. Membrane is Selective Permeability Allows some materials to pass, not all 3 types of diffusion in cells - Simple diffusion - lipid-soluble or small - to pass through pores - Facilitated diffusion - too big or not lipid-soluble; need protein carriers (channel or gated proteins) - Osmosis - movement of water across membrane from [hi] to [lo] Study the diagram below. It represents a container that is divided by a semi permeable membrane. A different solution in its initial state is shown on each side of the membrane. 1. Which substance(s) can move through the membrane? Why? 2. Which direction will the molecule(s) will move? To side I or II? 3. Which substance will move across fastest? Why? 4. How long will the molecule(s) will continue to move? Osmosis - How Cells Respond to Different Solutions 90% H2O 10% solute 85% H2O 15% solute 95% H2O 5% solute 90% H2O 10% solute 90% H2O 10% solute 90% H2O 10% solute Isotonic (no net movement of water) Hypotonic Hypertonic What solution would you give someone who is retaining water? Why shouldn’t you drink ocean water if you are thirsty? Another Passive Process Filtration Water & solutes forced through a membrane by pressure Pressure gradient (high to low) Happens in kidneys. Active Transport Processes Transport substances that can’t pass because: - too large - not lipid-soluble - against concentration gradient 2 common forms of active transport - Solute pumping - Bulk transport Solute pumping Amino acids, some sugars and ions are pumped ATP energizes protein carriers, moves substances against concentration gradients (from low to high, or up a gradient concentration. Sodium-Potassium Pumps Bulk Transport Exocytosis Moves out of cell by vesicle Endocytosis engulfed by vesicle & brought in 2 Types - Phagocytosis – cell eating - Pinocytosis – cell drinking Filtration Any direction as needed High to Low Channel or Gate Proteins Pressure through capillaries Anything dissolved in blood Water, urea, sugars, ions Protein Pumps