DOCSLIB.ORG

Facilitated Diffusion by Carrier Proteins, Secondary Active Transport, and Primary Active Transport

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Facilitated Diffusion by Carrier Proteins, Secondary Active Transport, and Primary Active Transport Movement of Molecules Across Membranes Sue Keirstead, Ph.D. Assistant Professor Dept. Integrative Biology and Physiology Stem Cell Institute 612 626 2290 [email protected] Movement of Molecules Across Membranes - Learning Objectives 1. List the chemical characteristics of molecules that are most likely to move by simple diffusion across the lipid bilayer of the plasma membrane and explain why. Explain the factors that Fick’s Law tells us determine the rate of diffusion through the lipid bilayer. 2. Explain why ions do not move through ion channels by only simple diffusion, whereas water does move through water channels by simple diffusion. Specifically, what, in addition to the concentration gradient, affects the movement of ions through ion channels? 3. Compare and contrast the ways in which channels and carrier proteins facilitate movement of ions across the plasma membrane. Consider specificity, energy requirements, mechanism of movement of solute, and saturation. 4. Differentiate the following processes based on 1) the necessity for and 2) source of energy driving the process and 3) the molecular pathway for: simple diffusion through the lipid bilayer, facilitated diffusion by carrier proteins, secondary active transport, and primary active transport. 5. Define saturation and explain how and why the transport of a molecule by a saturable mechanism such as facilitated diffusion by carrier proteins will differ from simple diffusion through the lipid bilayer. Draw a graph showing the rate of solute movement versus extracellular concentration for the two processes (see Figures 5.6 & 5.10). 6. Understand how a cell could be modified to increase or decrease the maximal rate of transport across the plasma membrane by carrier-mediated mechanisms (e.g. upregulation). Draw a second line on the graph in LO 5 to show the rate of transport after upregulation of the carrier proteins. 7. Describe how the distribution of proteins on the luminal (apical) and basolateral membranes of an intestinal epithelial cell permits the transcellular transport of glucose, sodium, and water from the lumen of the intestine to the interstitial fluid (see Figure 5.25). Consider the movement of glucose across the apical and basolateral membranes after a meal versus after a long night’s sleep (i.e. fasting). External environment O2 CO2 Integumentary system Nutrients Digestive system Cells Respiratory Internal environment system Interstitial Blood plasma fluid O2 CO2 Nitrogenous Nutrients wastes Nutrients Nitrogenous wastes Cardiovascular system Urinary system Urine Solid wastes Copyright © 2019 by John Wiley & Sons, Inc. All rights reserved. Fig 1.4 Small Intestine - Digestion - Absorption Fig 21.17 Mechanisms for Digestion: Enzymes Fig 21.18 Copyright © 2019 by John Wiley & Sons, Inc. All rights reserved. Mechanisms for nutrient absorption Absorptive Blood capillary Glucose and Secondary active cell Mono- of a villus galactose transport with Na+ Transport saccharides proteins Facilitated Facilitated diffusion Fructose diffusion Lacteal of Secondary active a villus + Amino acids transport with Na or facilitated Amino acids Dipeptides diffusion Facilitated Secondary active diffusion Tripeptides transport with H+ Short-chain fatty acids Simple Short-chain Simple diffusion fatty acids diffusion Triglycezride Chylomicron Long-chain fatty acids Simple diffusion Monoglycerides Micelle Microvillus of brush border on apical surface Basolateral surface Fig 21.20 Copyright © 2019 by John Wiley & Sons, Inc. All rights reserved. Lumen Apical (luminal) membrane 1 EPITHELIAL CELLS 2 3 Basolateral membrane 4 Interstitial fluid Blood capillary Fig 5.25 Diffusion across the lipid bilayer Extracellular fluid Nonpolar Small, uncharged Ions: Large, uncharged molecules: polar molecules: polar molecules: + + – O2, CO2, steroids H2O, urea Na , K , Cl Glucose Plasma membrane Cytosol Copyright © 2019 by John Wiley & Sons, Inc. All rights reserved. Fig 5.1 Extracellular fluid Plasma membrane Cytosol Concentration gradient (c) Carrier-mediated Simple diffusion Channel-mediated facilitated diffusion facilitated diffusion Copyright © 2016 by John Wiley & Sons, Inc. All rights reserved. Relationship between the rate of diffusion and the concentration gradient of the solute Diffusion rate Diffusion of solute Concentration gradient of solute Copyright © 2019 by John Wiley & Sons, Inc. All rights reserved. Fig 5.6 Movement through channels Extracellular fluid Plasma membrane Cytosol Concentration gradient (a) Simple (b) Channel-mediated (c) Carrier-mediated diffusion facilitated diffusion facilitated diffusion Copyright © 2019 by John Wiley & Sons, Inc. All rights reserved. Fig 5.5 K+ electrochemical gradient Extracellular fluid Plasma membrane Cytosol K+ K+ concentration K+ electrical K+ electrochemical gradient gradient gradient LO 2 What, in addition to concentration gradient, affects the movement of ions through ion channels? Copyright © 2019 by John Wiley & Sons, Inc. All rights reserved. Fig 5.3 Gated K+ channel Extracellular fluid Plasma membrane Cytosol Low [K+] Channel protein K+ electrochemical Pore gradient K+ Gate open Gate closed High [K+] Fig 5.7 Copyright © 2016 by John Wiley & Sons, Inc. All rights reserved. Extracellular fluid Plasma membrane Cytosol Solute to be transported Carrier protein A Carrier protein B Carrier protein C Copyright © 2016 by John Wiley & Sons, Inc. All rights reserved. Carrier protein-mediated Transport Primary Active Transport Facilitated Diffusion ATP ADP Secondary Active Transport Compare and contrast Facilitated Diffusion Solute to be transported Extracellular fluid Carrier protein Solute concentration Conformational gradient change Intracellular fluid Copyright © 2016 by John Wiley & Sons, Inc. All rights reserved. Extracellular fluid Plasma membrane Cytosol High [glucose] Glucose Glucose transporter 1 2 Glucose concentration gradient 3 Glucose Low [glucose] Copyright © 2016 by John Wiley & Sons, Inc. All rights reserved. 3. Compare and contrast the ways in which channels and carrier proteins facilitate movement of ions across the plasma membrane. Consider specificity, energy requirements, mechanism of movement of solute, and saturation (see CT 1.5). Diffusion rate rate Diffusion of solute Concentration gradient of solute Copyright © 2016 by John Wiley & Sons, Inc. All rights reserved. Transport maximum (Tm) Transport rate ofsolute Transport Concentration gradient of solute Copyright © 2019 by John Wiley & Sons, Inc. All rights reserved. LO 5 & 6 Fig 5.10 Primary Active Transport High [Na+] Low [K+] Extracellular fluid Na+/K+ ATPase 3 Na+ expelled 2K+ Na+ electrochemical K+ electrochemical gradient gradient P 3 Na+ ATP ADP P 2 K+ imported Intracellular fluid 1 2 3 4 Low [Na+] High [K+] Copyright © 2016 by John Wiley & Sons, Inc. All rights reserved. Secondary Active Transport Extracellular fluid High [Na+] Low [solute] Solute to be Na+ Carrier protein cotransported Na+ electrochemical Solute concentration gradient gradient 1 2 3 4 Low [Na+] / High [solute] Intracellular fluid Copyright © 2016 by John Wiley & Sons, Inc. All rights reserved. Na+/ glucose symporter (cotransporter) Extracellular fluid High [Na+] Low [glucose] Na+ electrochemical Glucose concentration gradient gradient + Na Glucose + Intracellular fluid Low [Na ] High [glucose] Copyright © 2016 by John Wiley & Sons, Inc. All rights reserved. Na+/ amino acid symporter Extracellular fluid Cytosol High [Na+] Low [amino acid] Na+ electrochemical Amino acid concentration gradient gradient Amino Na+ acid Low [Na+] High [amino acid] Intracellular fluid e.g. glutamate Copyright © 2016 by John Wiley & Sons, Inc. All rights reserved. Na+/ Ca2+ antiporter (exchanger) Extracellular fluid High [Na+] High [Ca2+] Ca2+ Na+ electrochemical Ca2+ electrochemical gradient gradient Na+ Low [Na+] Low [Ca2+] Intracellular fluid Copyright © 2016 by John Wiley & Sons, Inc. All rights reserved. Na+/ H+ antiporter Extracellular fluid Plasma membrane Cytosol HIgh [Na+] / High [H+] H+ Na+ electrochemical H+ electrochemical gradient gradient Na+ Low [Na+] / Low [H+] Copyright © 2016 by John Wiley & Sons, Inc. All rights reserved. .
Load more

Recommended publications
  • Osmosis, Diffusion, and Membrane Transport Bio 219 Napa Valley College Dr
    Osmosis, Diffusion, and Membrane Transport Bio 219 Napa Valley College Dr. Adam Ross Overview In order to understand how cells regulate themselves, we must first understand how things move into and out of cells Diffusion • Diffusion is the movement of particles from an area of high charge or concentration to an area of lower charge or concentration • Referred to as moving “down” a charge or concentration gradient • Ex. H+ ions in mitochondria moving through ATP synthase • Result of random molecular motion • Fick’s Law of Diffusion gives rate of diffusion: • Rate = P A (Cout – Cin) / (x) • Rate is proportional to permeability (P), surface area (A), concentration gradient (Cout – Cin); inversely proportional to diffusion distance or membrane thickness (x) Gradients • Concentration • Caused by unequal distribution of a substance on either side of the membrane • If the inside of a cell is negative, it will attract positively charged things • Electrical (charge) • Caused by unequal distribution of charge on either side of the membrane Diffusion Osmosis • Osmosis is the movement of solvent through a semi permeable membrane in order to balance the solute concentration on either side of the membrane. • In cells the solvent is water • Water can cross membranes Osmosis Osmolarity • Total concentration of all solutes in a solution • 1 Osm = 1 mole solute/ L • Have to account for both atoms in salts • 1M NaCl +1 L H2O → 1M Na+ + 1M Cl ≈ 2 Osm • Plasma = 290 mOsm Osmotic pressure • This is the actual driving force for net water movement • Depends on
    [Show full text]
  • Membrane Transport, Absorption and Distribution of Drugs
    Chapter 2 1 Pharmacokinetics: Membrane Transport, Absorption and Distribution of Drugs Pharmacokinetics is the quantitative study of drug movement in, through and out of the body. The overall scheme of pharmacokinetic processes is depicted in Fig. 2.1. The intensity of response is related to concentration of the drug at the site of action, which in turn is dependent on its pharmacokinetic properties. Pharmacokinetic considerations, therefore, determine the route(s) of administration, dose, and latency of onset, time of peak action, duration of action and frequency of administration of a drug. Fig. 2.1: Schematic depiction of pharmacokinetic processes All pharmacokinetic processes involve transport of the drug across biological membranes. Biological membrane This is a bilayer (about 100 Å thick) of phospholipid and cholesterol molecules, the polar groups (glyceryl phosphate attached to ethanolamine/choline or hydroxyl group of cholesterol) of these are oriented at the two surfaces and the nonpolar hydrocarbon chains are embedded in the matrix to form a continuous sheet. This imparts high electrical resistance and relative impermeability to the membrane. Extrinsic and intrinsic protein molecules are adsorbed on the lipid bilayer (Fig. 2.2). Glyco- proteins or glycolipids are formed on the surface by attachment to polymeric sugars, 2 aminosugars or sialic acids. The specific lipid and protein composition of different membranes differs according to the cell or the organelle type. The proteins are able to freely float through the membrane: associate and organize or vice versa. Some of the intrinsic ones, which extend through the full thickness of the membrane, surround fine aqueous pores. CHAPTER2 Fig.
    [Show full text]
  • Cellular Transport Notes About Cell Membranes
    Cellular Transport Notes @ 2011 Center for Pre-College Programs, New Jersey Institute of Technology, Newark, New Jersey About Cell Membranes • All cells have a cell membrane • Functions: – Controls what enters and exits the cell to maintain an internal balance called homeostasis TEM picture of a – Provides protection and real cell membrane. support for the cell @ 2011 Center for Pre-College Programs, New Jersey Institute of Technology, Newark, New Jersey 1 About Cell Membranes (continued)‏ 1.Structure of cell membrane Lipid Bilayer -2 layers of phospholipids • Phosphate head is polar (water loving)‏ Phospholipid • Fatty acid tails non-polar (water fearing)‏ • Proteins embedded in membrane Lipid Bilayer @ 2011 Center for Pre-College Programs, New Jersey Institute of Technology, Newark, New Jersey Polar heads Fluid Mosaic love water Model of the & dissolve. cell membrane Non-polar tails hide from water. Carbohydrate cell markers Proteins @ 2011 Center for Pre-College Programs, New Jersey Institute of Technology, Newark, New Jersey 2 About Cell Membranes (continued)‏ • 4. Cell membranes have pores (holes) in it • Selectively permeable: Allows some molecules in and keeps other molecules out • The structure helps it be selective! Pores @ 2011 Center for Pre-College Programs, New Jersey Institute of Technology, Newark, New Jersey Structure of the Cell Membrane Outside of cell Carbohydrate Proteins chains Lipid Bilayer Transport Protein Phospholipids Inside of cell (cytoplasm)‏ @ 2011 Center for Pre-College Programs, New Jersey Institute of Technology, Newark, New Jersey 3 Types of Cellular Transport • Passive Transport cell‏doesn’t‏use‏energy 1. Diffusion 2. Facilitated Diffusion 3. Osmosis • Active Transport cell does use energy 1.
    [Show full text]
  • CO2 Permeability of Biological Membranes and Role of CO2 Channels
    membranes Review CO2 Permeability of Biological Membranes and Role of CO2 Channels Volker Endeward, Mariela Arias-Hidalgo, Samer Al-Samir and Gerolf Gros * Molekular-und Zellphysiologie, AG Vegetative Physiologie–4220–Medizinische Hochschule Hannover, 30625 Hannover, Germany; [email protected] (V.E.); [email protected] (M.A.-H.); [email protected] (S.A.-S.) * Correspondence: [email protected]; Fax: +49-511-5322938 Received: 17 September 2017; Accepted: 18 October 2017; Published: 24 October 2017 Abstract: We summarize here, mainly for mammalian systems, the present knowledge of (a) the membrane CO2 permeabilities in various tissues; (b) the physiological significance of the value of the CO2 permeability; (c) the mechanisms by which membrane CO2 permeability is modulated; (d) the role of the intracellular diffusivity of CO2 for the quantitative significance of cell membrane CO2 permeability; (e) the available evidence for the existence of CO2 channels in mammalian and artificial systems, with a brief view on CO2 channels in fishes and plants; and, (f) the possible significance of CO2 channels in mammalian systems. Keywords: CO2 permeability; membrane cholesterol; protein CO2 channels; aquaporins; Rhesus proteins; aquaporin-1-deficient mice 1. Introduction This review intends to update the state of this field as it has been given by Endeward et al. [1] in 2014. In addition, we attempt to give a compilation of all of the lines of evidence that have so far been published demonstrating the existence of protein CO2 channels and their contributions to membrane CO2 permeability. We also give a compilation of the recently described remarkable variability of the CO2 permeability in mammalian cell membranes.
    [Show full text]
  • Cell Transport
    Cells and their Environment Transport occurs across the cell membrane and helps a cell to maintain homeostasis. Cell part responsible: 5/16/14 1 1. Movement of materials across the membrane is called transport. A. Passive Transport - WITHOUT the use of energy • Driven by Kinetic energy/Brownian motion B. Active Transport - WITH the use of energy- against a concentration gradient 5/16/14 2 2. Concentration Gradient- difference in concentration from one area to another Visual Concept 5/16/14 3 3. Diffusion is passive/no energy. a) Diffusion- high to low concentration. b) Quicker at higher temps c) Occurs until an equilibrium is reached 5/16/14 4 4. Osmosis is the diffusion of water molecules directly through the cell's membrane. 5/16/14 5 5. If a cell is in a solution that is….. a) Hypertonic it shrinks (higher concentration of dissolved particles outside than inside of the cell) b) Hypotonic it expands (lower concentration of dissolved particles outside compared with inside of the cell) c) Isotonic no change (same concentration of dissolved particles outside as inside of the cell. 5/16/14 6 Graphic Organizer Hypertonic Hypotonic Isotonic DRAWINGS: For each category, draw a cell in solution. For each picture, show solute particles in your solution and also in your cell. Label solvent line and solute particles. Show if water is entering or leaving the cell using arrows. WRITE ABOUT IT: For each category, answer the following in complete sentences. 1) Is water moving into or out of the cell, or neither? 2) Is the cell shrinking, expanding or staying the same? 3) Are there more solute particles inside 5/16/14the cell or in solution, or neither? 7 Question: What would happen to an animal cell placed into a HYPERtonic solution? 5/16/14 8 (It would shrink- plasmolysis) 6.
    [Show full text]
  • Amino Acids, Peptides, and Proteins
    1/11/2018 King Saud University College of Science Department of Biochemistry Biomembranes and Cell Signaling (BCH 452) Chapter 3 Diffusion, Channels and Transport Systems Prepared by Dr. Farid Ataya http://fac.ksu.edu.sa/fataya Lect Topics to be covered No. Role of cell surface carbohydrates in recognise ion, as receptor of antigens, 7 hormones, toxins, viruses and bacteria. Their role in histocompatibility and cell-cell adhesion. Diffusion. 8 Diffusion across biomembranes. Ficks law. Structural types of channels (pores): -type, -barrel, pore forming toxins, ionophores. Functional types of channels (pores): voltage-gated channels e.g. sodium channels, ligand-gated channels e.g. acetylcholine receptor (nicotinic-acetylcholine channel), c-AMP regulated. Gap junctions and nuclear pores. 9 Transport systems: Energetics of transport systems, G calculation in each type. Passive Transport (facilitated diffusion). 1 1/11/2018 No. Topics to be covered Lect Kinetic properties. 9 Passive transport: Glucose transporters (GLUT 1 to5), - C1 , HCO3 exchanger (anion exchanger protein) in erythrocyte membrane Kinetic properties. 10 Active transport: Types of active transport: Primary ATPases (Primary active transporters): P transporters (e.g. Na+, K+, ATPase) First assessment Exam ATP binding cassettes (ABC transports) 11 (e.g. cystic fibrosis transmembrane conductance regulator-chloride transport). Multidrug resistance protein transporter. V transporters, F transporters. Secondary active transporters (e.g. Na+ -dependent transport of glucose and amino acids). To be covered under intestinal brush border Transport of large molecules (Macromolecules) 12 Types: Exocytosis, Endocytosis-pinocytosis and phagocytosis Types of pinocytosis: Absorptive pinocytosis, characteristics and examples. Fluid phase pinocytosis, characteristics and examples The role of cell surface carbohydrates: Glycoproteins Membrane glycoproteins are proteins that contain 1-30% carbohydrate in their structure.
    [Show full text]
  • Concentration Gradient; Within a System, Different Substances in the Medium Will Each Diffuse at Different Rates According to Their Individual Gradients
    Biomolecules Biological Macromolecules • Life depends on four types of organic macromolecules: 1. Carbohydrates 2. Lipids 3. Proteins 4. Nucleic acids 1. Carbohydrates • Contain carbon, hydrogen and oxygen in a ratio of 1:2:1 • Account for less that 1% of body weight • Used as energy source • Called saccharides Carbohydrates • Compounds containing C, H and O • General formula : Cx(H2O)y • All have C=O and -OH functional groups. • Classified based on • Size of base carbon chain • Number of sugarunits • Location of C=O • Stereochemistry Types of carbohydrates • Classifications based on number of sugarunits in total chain. • Monosaccharides - single sugarunit • Disaccharides - two sugarunits • Oligosaccharides - 2 to 10 sugarunits • Polysaccharides - more than 10units • Chaining relies on ‘bridging’ of oxygenatoms • glycoside bonds Monosaccharides • Based on location of C=O H CH2OH | | C=O C=O | | H-C-OH HO-C-H | | H-C-OH H-C-OH | | H-C-OH H-C-OH | | CH2OH CH2OH Aldose Ketose - aldehyde C=O - ketone C=O Monosaccharide classifications • Number of carbon atoms in the chain H H | H | C=O H | C=O | | C=O | H-C-OH C=O | H-C-OH | | H-C-OH | H-C-OH | H-C-OH | H-C-OH H-C-OH | H-C-OH | | H-C-OH | CH2OH | H-C-OH CH2OH | CH2OH CH2OH triose tetrose pentose hexose Can be either aldose or ketose sugar. Stereoisomers • Stereochemistry • Study of the spatial arrangement ofmolecules. • Stereoisomers have • the same order and types of bonds. • different spatial arrangements. • different properties. • Many biologically importantchemicals, like sugars, exist as stereoisomers. Your body can tell the difference.
    [Show full text]
  • Membrane Processes Practice Quiz/AP Biology
    Membrane Processes Practice Quiz/AP Biology Choose the response which best completes the following statements or answers the following questions. 1. If a solution outside a cell is more concentrated so that the cell loses water to its environment, the external solution is said to be __________ to the cell contents. (1.) hypertonic (2.) in equilibrium (3.) isotonic (4.) hypotonic 2. Which mechanism requires energy? (1.) facilitated diffusion (2.) osmosis (3.) diffusion (4.) active transport 3. Pinching in of fluids by a unicellular organism is the process of (1.) phagocytosis (2.) osmosis (3.) pinocytosis (4.) exocytosis (5.) facilitated diffusion 4. Certain types of lymphocytes (white blood cells) in the lymph nodes ingest bacteria and debris. This function most likely occurs by (1.) exocytosis (2.) passive transport (3.) phagocytosis (4.) pinocytosis (5.) facilitated transport 5. Osmosis is a process that (1.) involves the movement of particles from saturated solutions (2.) moves water molecules from an area of higher concentration to an area of lower concentration, using energy (3.) involves the active transport of dissolved solids (4.) continues until the medium on each side of the membrane has become hypertonic (5.) equalizes the concentration of particles by the movement of water molecules Use the information below and your knowledge of biology to answer questions 6 through 7 which follow the reading passage. Each student in a biology laboratory received two solutions. One solution was distilled water. The other was a salt solution with concentrations of salts slightly greater than that of a living cell. The solutions were labeled X and Y, respectively.
    [Show full text]
  • Chapter 4 Movement of Molecules Across Cell Membranes = Trans-Membrane Traffic
    Chapter 4 Movement of Molecules Across Cell Membranes = Trans-Membrane Traffic Diffusion: solute moves down its concentration gradient: • simple diffusion: small (e.g., oxygen, carbon dioxide) lipid soluble (e.g., steroids) • facilitated diffusion: requires transporter (e.g., glucose) Chapter 4 Movement of Molecules Across Cell Membranes = Trans-Membrane Traffic (cont.) Active transport: solute moves against its concentration gradient: • primary active transport: ATP directly consumed (e.g., Na+ K+ATPase) • secondary active transport: energy of ion gradient (usually Na+) used to move second solute (e.g., nutrient absorption in gut) Exo- and endo- cytosis: large scale movements of molecules Figure 4-1 START: Initially higher concentration of molecules randomly move toward lower concentration. Over time, solute molecules placed in a solvent will evenly distribute themselves. Diffusional equilibrium is the result (Part b). At time B, some glucose has crossed into side Figure 4-2 2 as some cross into side 1. Note: the partition between the two compartments is a membrane that allows this solute to move through it. Net flux accounts for solute Figure 4-3 movements in both directions. 3 cartoon models of integral membrane proteins that function as ion channels; the regulated opening and closing of these channels is the basis of how neurons function. Figure 4-5 A thin shell of positive (outside) and negative (inside) charge provides the electrical gradient that drives ion movement across the membranes of excitable cells. Figure 4-6 Figure 4-7 The opening and closing of ion channels results from conformational changes in integral proteins. Discovering the factors that cause these changes is key to understanding excitable cells.
    [Show full text]
  • Bio102 Problems Transport Across Membranes
    Bio102 Problems Transport Across Membranes 1. Antiport is one type of A. facilitated transport. B. active transport. C. endocytosis. D. channel protein. E. carrier protein. 2. Pinocytosis is one type of A. exocytosis. B. phagocytosis. C. facilitated transport. D. endocytosis. E. diffusion. 3A. Consider a bacterial cell that is hypertonic in comparison to its environment. Will water move into the cell or out of the cell? 3B. We now add a large amount of either O2, N2, or Pyruvate to the fluid surrounding the cell. Which one will have the biggest effect on the movement of water? Will its addition increase or decrease the movement of water? Please explain your answer. 4. Imagine a bacterial cell living in a test tube under the following conditions: K+ Mg2+ Na+ inside the cell 50 mM 0.1 mM 10 mM outside the cell 10 mM 3 mM 150 mM 4A. Is the G value for Mg2+ movement into the cell positive, negative or zero? 4B. Under these conditions, is the solution hypotonic, hypertonic or isotonic relative to the cell? 4C. Under these conditions, will the net movement of water be into the cell or out of the cell? Why? 4D. If we added a large concentration (say, 1M) of CO2 to the outside of the cell, it would have no effect on the net movement of water. Why not? 4E. If the fatty acid tails in the phospholipids that make up this cell’s membranes were more saturated, would that increase or decrease the rate at which water moves? Or would it have no effect? Please explain.
    [Show full text]
  • Transport-That-Requires-Energy.Pdf
    Transport That Requires Energy Simmonds enroot his molluscs misperceived ablaze, but equinoctial Allah never indurating so begrudgingly. High-handed and cloudy impracticablyGarwood never or inwallsteeter inclemently. miserably when Torey vindicate his pleons. Alphabetic and carpeted Brad often bespangles some adipose As you dribbled the transport requires the remaining part of transport of lower to select one question pool, the inflammation of concentration gradient on the pressure Passive transport does state require energy There after four main types of passive transport simple diffusion facilitated diffusion osmosis and filtration. In this case, they can pass into and out of the cell with the assistance of plasma membrane proteins through a process called facilitated diffusion. Second shows transport. Add a record of originality! Catherine Shaffer is a freelance science and health writer from Michigan. If there are transported as before switching accounts for active transport, that transport requires energy. Same on one solute against their transported in higher concentration gradient with a certain times a cross. Chapter 4. This process requires the butcher of energy and specify known as active transport As with facilitated diffusion special transporters in the membrane are used to move. Cellular energy as acetylcholine across alveolar membranes are used it prevents excessive water? Active vs passive transport- Definition 1 Major Differences. For recording, notably without directly coupling to ATP. Read through these molecules have no recommended web sites because they are likely if any device. Molecules crossing a membrane using active transport go from. Such as a type requires atp for example, secondary active transport allows passage below some other.
    [Show full text]
  • The Differences in Solute Concentration Across Cell Membranes Are Created and Maintained by Transport Mechanisms in Cell Membra
    Cellular Physiology Membrane Physiology Body Fluids: 1) Water: (universal solvent) Body water varies based on of age, sex, mass, and body composition H2O ~ 73% body weight Low body fat; Low bone mass H2O (♂) ~ 60% body weight H2O (♀) ~ 50% body weight ♀ = body fat / muscle mass H2O ~ 45% body weight Cellular Physiology Cellular Physiology In biological systems, [solute] are usually quite low and are expressed in millivolumes (10-3) Body Fluids: Body Fluids: Units for measuring [solute]: 1) Water: (universal solvent) 2) Solutes: A) moles / liter (mol / L) Total Body Water Urea mole = 6.02 x 1023 molecules Volume = 40 L A glucose concentration of 1 mol / L has (60% body weight) 6.02 x 1023 glucose molecules in 1 L of solution A) Non-electrolytes (do not dissociate in solution – neutral) B) osmoles / liter (osmol / L) Plasma • Mostly organic molecules osmole = # of particles into which a (e.g., glucose, lipids, urea) solute dissociates in solution Intracellular Fluid (ICF) Interstitial 1 mol / L of NaCl is equal to 2 osmol / L Fluid 3 = Volume Carbonic because NaCl dissociates into two particles Volume = 25 L acid Volume = 12 L (40% body weight) C) equivalents / liter (Eq / L) Plasma membrane Plasma equilavent = # of moles x valence L B) Electrolytes ++ 1 mol / L of CaCl2 equates to 2 Eq / L of Ca (dissociate into ions in solution – charged) and 2 Eq / L of Cl- in solution • Inorganic salts D) pH (used to express H+ concentration) Extracellular Fluid (ECF) • Inorganic / organic acids + pH = -log10 [H ] Volume = 15 L • Proteins A [H+] of
    [Show full text]