Science - Cell Tour PDF
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2008
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This document is an outline of cell biology. It discusses various cell types, the functions of different organelles, DNA and protein synthesis. The outline is geared towards advanced high school biology students and is part of the AP Biology curriculum.It includes information about prokaryotic and eukaryotic cells.
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Tour of the Cell 1 AP Biology 2007-2008 2 Prokaryote Types of cells bacteria cells - no organelles ·...
Tour of the Cell 1 AP Biology 2007-2008 2 Prokaryote Types of cells bacteria cells - no organelles · Prokaryote X eukaryote - organelles ⑪ * Eukaryote Eukaryote AP Biology animal cells plant cells Why organelles? Specialized structures mitochondria specialized functions cilia or flagella for locomotion Containers partition cell into compartments Loading… create different local environments separate pH, or concentration of materials chloroplast distinct & incompatible functions lysosome & its digestive enzymes Membranes as sites for chemical reactions unique combinations of lipids & proteins Golgi embedded enzymes & reaction centers chloroplasts & mitochondria AP Biology ER Cells gotta work to live! What jobs do cells have to do? make proteins proteins control every cell function make energy for daily life for growth make more cells growth repair renewal AP Biology Building Proteins Loading… AP Biology 2007-2008 Proteins do all the work! proteins cells DNA Repeat after me… organis Proteins do all the AP Biology work! Cells functions Building proteins I readDNA instructions build proteins process proteins / ↳ folding modifying removing amino acids adding other molecules e.g, making glycoproteins : for cell membrane address & transport proteins AP Biology Building Proteins Organelles involved nucleus DNA ess - - - ribosomes - endoplasmic reticulum (ER) synthesizes protein enodiver oryfolding - - Golgi apparatus - - vesicles transports - The Protein Assembly Line Golgi nucleus ribosome ER vesicles apparatus AP Biology & Nucleus DNA Function chromosom e protectsD DNA histone protein Structure nuclear envelope MINA - double membrane escape ↳ membrane fused in spots to create pores From allows large macromolecules to pass through nuclea r pores nuclea What kind of r pore molecules need to nucleolu AP Biology pass through? s nuclear 1 nuclear membran e transcription production of mRNA DN A from DNA in nucleus mRN Nucleu A s 2 small nuclear ribosoma mRNA travels from translation pore l subunit nucleus to ribosome mRN A in cytoplasm through large nuclear pore ribosoma l subunit AP Biology cytoplas m Loading… AP Biology - Nucleolus Function ribosome production build ribosome subunits from rRNA & proteins exit through nuclear pores to cytoplasm & combine to form functional ribosomes large subunit rRNA & small proteins subunit AP Biology ribosom nucleolus large Ribosomes subuni t Function small protein production subuni t Structure rRNA & protein 2 subunits combine 0.08m m m Ribosome s Roug h ER Smoot h ER AP Biology Types of Ribosomes orem 1 Free ribosomes Fluidop = Cy suspended in cytosol - synthesize proteins that function in cytosol 2 Bound ribosomes - attached to endoplasmic reticulum Rough - synthesize proteins for export or for membranes AP Biology membrane Endoplasmic Reticulum Function # Facing dinging - processes proteins manufactures membranes synthesis & hydrolysis of many compounds Structure membrane connected to nuclear envelope & extends throughout cell AP Biology Types of ER rough smooth AP Biology Smooth ER function Membrane production Many metabolic processes synthesis synthesize lipids = oils, phospholipids, steroids & sex hormones hydrolysis hydrolyze glycogen into glucose in liver - detoxify drugs & poisons in z liver ex. alcohol & barbiturates AP Biology Membrane Factory Build new membrane synthesize phospholipids builds membranes ER membrane expands bud off & transfer to other parts of cell that need membranes AP Biology Rough ER function Produce proteins for export out of cell protein secreting cells packaged into transport vesicles for export revide oug Which cells busfam In have lot of rough ER? AP Biology Synthesizing proteins cisternal space polypeptide signal sequence ribosome ribosome membrane of mRNA endoplasmic reticulum cytoplasm AP Biology Golgi Apparatus Function finishes, sorts, tags & ships cell products like “UPS shipping department” ships products in vesicles membrane sacs “UPS trucks” secretor y Which cells vesicles have lots of Golgi? AP Biology transport Golgi Apparatus ↓ e faces AP Biology Vesicle transport protein vesicle migrating fusion budding transport of vesicle from rough vesicle with Golgi ER apparatus ribosom e AP Biology nucleus I. endoplasmic reticulum ↳ 3 Does protein : DNA on its way! TO: ↳ % RNA vesicle ↓ TO: TO: vesicle 1 ribosomes - ↳ TO: protein finished & protein - > - v. Golgi apparatus Making Proteins Regents Biology Putting it together… Making proteins nucleu cell snuclear membrane protein pore secreted rough ER ribosom vesicl e e aif fac proteins trane smooth ER transport Golgi vesicle apparatu AP Biology cytoplas s moreo comp AP Biology AP Biology Any Questions!! AP Biology 2007-2008 Tour of the Cell 2 AP Biology 2007-2008 Cells gotta work to live! What jobs do cells have to do? make proteins in proteins control every I cell function make energy · for daily life for growth make more cells growth ins repair renewal AP Biology Making Energy ATP Loading… AP Biology 2007-2008 Cells need power! Making energy take in food & digest it - take in oxygen (O2) - make ATP - remove waste - ATP AP Biology Where Lysosomes old organelles go to die! Function little “stomach” of the cell digests macromolecules “clean up crew” of the cell organelles Loading… cleans up broken down Structure vesicles of digestive & enzymes synthesized by rER, transferred AP Biology to Golgi only in animal cells clear ment 1960 | 1974 Lysosomes white blood cells attack & Digests cleani AA destroy invaders = digest them in lysosomes - uP 1974 Nobel prize: Christian de Duve AP Biology Lysosomes discovery in 1960s Lysosomes = Cellular digestion Synthesize ↓ Lysosomes fuse with food vacuoles polymers transferred so digested into galgi monomers pass to cytosol to become d nutrients of cell vacuole lyso– = breaking things apart - AP Biology = body –some Of Lysosomal enzymes vericle > - digestive enzymes Lysosomal enzymes work best at pH 5 H = organelle creates custom pH more said how? ↓ proteins in lysosomal membrane pump H+ ions from the cytosol into lysosome why? ↳ in ture enzymes are very sensitive to pH cysosome why? bena enzymes are proteins — pH affects structure why evolve digestive enzymes which function at pH different from cytosol? digestive enzymes won’t function well if some leak into cytosol = don’t want to digest yourself! AP Biology When things go bad… Diseases of lysosomes are often fatal digestive enzyme not working in lysosome - picks up biomolecules, but can’t digest one lysosomes fill up with undigested material grow larger & larger until disrupts cell & organ function - lysosomal storage diseases more than 40 known diseases example: Tay-Sachs disease build up undigested fat in brain cells AP Biology Lysosomal storage diseases Lipids Gaucher’s disease Niemann-Pick disease Tay Sachs Glycogen & other poylsaccharides Farber disease Krabbe disease Proteins Schindler’s disease AP Biology But sometimes cells need to die… Lysosomes can be used to kill cells when they are supposed to be destroyed some cells have to die for proper - development in an organism I Loading… - apoptosis “auto-destruct” process lysosomes break open & kill cell ex: tadpole tail gets re-absorbed when it turns into a frog ex: loss of webbing between your fingers during fetal development AP Biology syndactyly Fetal development OR 6 weeks Example Losis a POP 15 weeks AP Biology Apoptosis programmed destruction of cells in multi- cellular organisms programmed development control of cell growth example: if cell grows uncontrollably this self-destruct mechanism is triggered to remove damaged cell cancer must over-ride this to enable tumor growth AP Biology Making Energy Cells must convert incoming energy to forms that they can use for work mitochondria: fromMglucose toM ATP in plantATP chloroplasts: > - only from m sunlight to ATP & carbohydrates ATP = active energy In carbohydrates = stored energy plante ATP + AP Biology Mitochondria & Chloroplasts ↓ Important to see the similarities very Similar transform energy generate ATP Emboyne a double membranes = 2 membranes semi-autonomous organelles move, change shape, divide internal ribosomes, DNA & enzymes AP Biology Mitochondria Function cellular respiration generate ATP from breakdown of sugars, fats & other fuels in the presence of oxygen break down larger molecules into smaller to generate energy = catabolism generate energy in presence of O2 = aerobic respiration AP Biology Mitochondria Structure 2 membranes smooth outer membrane highly folded inner membrane cristae fluid-filled space between 2 membranes internal fluid-filled space mitochondrial matrix DNA, ribosomes & enzymes Why 2 membranes? increase surface area for membrane- AP Biology bound enzymes that synthesize ATP Mitochondria AP Biology Membrane-bound Enzymes glucose + oxygen carbon + water + energy dioxide C6H12O6+ 6O2 AP Biology 6CO2 + 6H2O + ATP Dividing Mitochondria Who else divides like that? What does this tell us about AP Biology the evolution of eukaryotes? Mitochondria Almost all eukaryotic cells have mitochondria there may be 1 very large mitochondrion or 100s to 1000s of individual mitochondria number of mitochondria is correlated with aerobic metabolic activity more activity = more energy needed = more mitochondria What cells would have a lot of More mitochondria? mitochondria active cells: & / muscle cells nerve cells AP Biology Mitochondria are everywhere!! animal cells plant cells AP Biology Chloroplasts · Chloroplasts areA plant organelles class of plant structures = plastids amyloplasts store starch in roots & tubers chromoplasts store pigments for fruits & flowers chloroplasts store chlorophyll & function in photosynthesis in leaves, other green structures of plants & in eukaryotic algae AP Biology Chloroplasts Structure 2 membranes stroma = internal fluid-filled space DNA, ribosomes & enzymes thylakoids = membranous sacs where ATP is made grana = stacks of thylakoids Why internal sac membranes? increase surface area for membrane-bound enzymes that synthesize ATP AP Biology Membrane-bound Enzymes carbon + water + energy glucose + oxygen dioxide 6CO2 + 6H2O + light AP Biology C6H12O6 + 6O2 energy Chloroplasts Function - photosynthesis generate ATP & synthesize sugars - transform solar energy into chemical energy produce sugars from CO2 & H2O Mitochondria P Live > Semi-autonomous - moving, changing shape & dividing can reproduce by pinching in two Who else divides like that? AP Biology bacteria! Chloroplasts Why are chloroplasts green? AP Biology AP Biology Mitochondria & chloroplasts are different Organelles not part of endomembrane system Grow & reproduce semi-autonomous organelles Loading… Proteins primarily from free ribosomes in cytosol & a few from their own ribosomes Own circular chromosome directs synthesis of proteins produced by own ↓ internal ribosomes Who else has a circular ribosomes chromosome like bacterial not ribosomes bound within a nucleus? bacteria AP Biology 1981 | ?? Endosymbiosis theory Mitochondria & chloroplasts were once free living bacteria engulfed by ancestral eukaryote Endosymbiont > - theory cell that lives within another cell (host) as a partnership evolutionary advantage rokaryote 45 for both X Mitochondr anioroplate one supplies energy the other supplies raw materials & protection haukaryote Lynn Margulis AP Biology U of M, Amherst Endosymbiosis theory Evolution of eukaryotes AP Biology Compare the equations Photosynthesis Chloroplate carbon + water + energy glucose + oxygen t dioxide 6CO2 + 6H2O + light C6H12O6 + 6O2 energy Respiration V glucose + oxygen carbon + water + energy dioxide C6H12O6+ 6O2 6CO2 + 6H2O + ATP AP Biology The Great ENERGY Circle of Life sun Photosynthesis plants ATP glucose + O2 CO2 + H2O sugar Respiration animals & plants ATP AP Biology food vacuoles Food & water storage plant cells central vacuole & O animal cells contractile AP Biology vacuole Vacuoles & vesicles Function little “transfer ships” Food vacuoles phagocytosis, fuse with lysosomes Contractile vacuoles in freshwater protists, pump excess H2O out of cell Central vacuoles in many mature plant cells AP Biology Vacuoles in plants Functions storage stockpiling proteins or inorganic ions depositing metabolic byproducts storing pigments storing defensive compounds against herbivores selective membrane control what comes in or goes out AP Biology Peroxisomes Other digestive enzyme sacs in both animals & plants breakdown fatty acids to sugars easier to transport & use as energy source detoxify cell detoxifies alcohol & other poisons produce peroxide (H2O2) must breakdown H2O2 H2O AP Biology Putting it all together AP Biology animal cells plant cells Any Questions?? AP Biology 2007-2008 Tour of the Cell 3 AP Biology 2007-2008 Cells gotta work to live! What jobs do cells have to do? make proteins proteins control every cell function make energy for daily life for growth make more cells * growth repair renewal AP Biology Making New Cells Loading… AP Biology 2007-2008 Cytoskeleton Function structural support maintains shape of cell provides anchorage for organelles protein fibers ! microfilaments, intermediate filaments, microtubules motility - movement cell locomotion cilia, flagella, etc. regulation organizes structures & activities of cell AP Biology Cytoskeleton actin Loading… microtubule nuclei AP Biology Centrioles Cell division X Nuante sex in animal cells, pair of centrioles organize microtubules spindle fibers - # ~ eude once ridf guide chromosomes in mitosis AP Biology Any Questions?? AP Biology 2007-2008 The Cell Membrane AP Biology 2007-2008 Phosphat Phospholipids e “attracted to Phosphate head water water” hydrophilic > - live Fatty acid tails i hydrophobic - Dont water Fatty acid Arranged as a bilayer “repelled by personalitie water” Aaaah, one of those structure– function AP Biology examples Arranged as a Phospholipid bilayer Serves as a cellular barrier / border sugar H2O salt polar hydrophili c Loading… heads nonpolar hydrophobi impermeable to polar molecules c tails polar hydrophili c heads lipids waste AP Biology Cell membrane defines cell Cell membrane separates living cell from aqueous environment thin barrier = 8nm thick Controls traffic in & out of the cell allows some substances to cross more easily than others hydrophobic (nonpolar) vs. hydrophilic (polar) AP Biology Permeability to polar molecules? Membrane becomes semi-permeable via protein channels specific channels allow specific material across cell membrane Loading… inside cell H2O aa sugar NH3 AP Biology salt outside cell Cell membrane is more than lipids… Transmembrane proteins embedded in phospholipid bilayer create semi-permeabe channels lipid bilayer protein channels membrane in lipid bilyer membrane AP Biology Why are proteins the perfect molecule to build structures in the cell membrane? and dinferent mine hi i · ↓ AP Biology 2007-2008 Classes of amino acids What do these amino acids have in common? nonpolar & AP Biology hydrophobic Classes of amino acids What do these amino acids have in common? I like the polar ones the best! AP Biology polar & hydrophilic Proteins domains anchor molecule Polar Within membrane areas withinhydrophobic of protein nonpolar amino acids ↳ anchors protein into membrane On outer surfaces of membrane in fluid polar amino acids out i hydrophilic f extend into extracellular fluid & into cytosol Nonpolar areas of protein AP Biology Examples Retinal chromophor e H+ H + Eniz NH 2 aquaporin = water channel in bacteria Porin H2O - Loading… monomer b -pleated sheets Bacterial Nonpolar outer (hydrophobic) COO membran a -helices in H e Cytoplas the H+ cell membrane H + m proton pump channel in photosynthetic bacteria function through conformational change = AP Biology H2O protein changes shape Many Functions of Membrane Proteins “Channel” Outsid e Plasma membran e Insid e Transporter - Enzym Cell e surface activity receptor - “Antigen” T Cell surface Cell Attachment to the identity - AP Biology cytoskeleton = adhesion - - marker Membrane Proteins Proteins determine membrane’s specific functions cell membrane & organelle membranes each have unique collections of proteins Classes of membrane proteins: - peripheral proteins loosely bound to surface of membrane ex: cell surface identity marker (antigens) integral proteins ↳ penetrate lipid bilayer, usually across whole membrane transmembrane protein ex: transport proteins channels, permeases (pumps) AP Biology Cell membrane must be more than lipids… In 1972, S.J. Singer & G. Nicolson proposed that membrane proteins are inserted into the phospholipid bilayer Erexture It’s like a fluid… of It’s like a mosaic… mixturethings It’s the & Fluid Mosaic Model! &mem braine AP Biology Membrane is a - collage of proteins & other molecules embedded - in the fluid matrix of the lipid bilayer Glycoprotei Extracellular n fluid Glycolipi g d g Phospholipid s O Cholestero * O Periphera l Transmembrane proteins l Cytoplas Filaments of protein m cytoskeleto AP Biology n 1972, S.J. Singer & G. Nicolson proposed Fluid Mosaic Model Membrane carbohydrates Play a key role in cell-cell recognition ability of a cell to distinguish one cell from another antigens important in organ & tissue development basis for rejection of foreign cells by immune system AP Biology Any Questions?? AP Biology Movement across the Cell Membrane AP Biology 2007-2008 Diffusion 2nd Law of Thermodynamics governs biological systems universe tends towards disorder (entropy) Diffusion movement from HIGH LOW concentration AP Biology Simple Diffusion Move from HIGH to LOW concentration “passive transport” > - regular no energy needed movement of water AP Biology diffusion osmosis Facilitated Diffusion -regularn nig Diffusion through protein channels ↓ channels move specific molecules across low cell membrane no energy needed facilitated = with help - open channel = fast transport HIGH LOW AP Biology “The Bouncer” now Active Transport ↓ high Cells may need to move molecules against concentration gradient conformational shape change transports solute from one side of membrane to other protein “pump” “costs” energy = ATP conformational change LOW ATP HIGH AP Biology “The Doorman” Active transport Many models & mechanisms ATP ATP antiport symport AP Biology Getting through cell membrane Passive Transport Simple diffusion diffusion of nonpolar, hydrophobic molecules lipids HIGH LOW concentration gradient - Facilitated transport diffusion of polar, hydrophilic molecules through a protein channel HIGH - LOW concentration gradient Active transport diffusion against concentration gradient LOW HIGH uses a protein pump requires ATP ATP AP Biology Transport summary simple diffusion facilitated diffusion E active ATP transport AP Biology How about large molecules? Moving large molecules into & out of cell through vesicles & vacuoles endocytosis > cell & into - phagocytosis = “cellular eating” pinocytosis = “cellular drinking” cell exocytosis of > - out AP Biology exocytosis - Endocytosis fuse with phagocytosis lysosome for "Food - digestion - pinocytosis W non-specific & process "drink triggered by receptor-mediated molecular endocytosis - signal - AP Biology The Special Case of Water Movement of water across the cell membrane AP Biology 2007-2008 Osmosis is just diffusion of water Water is very important to life, so we talk about water separately more Enter Diffusion of water from Hypo HIGH concentration of water to Loading… LOW concentration of water need across a semi-permeable membrane AP Biology Concentration of water Direction of osmosis is determined by comparing total solute concentrations Hypertonic - more solute, less water Hypotonic - less solute, more water Isotonic - equal solute, equal water more water water less water hypotonic hypertonic AP Biology net movement of water Managing water balance Cell survival depends on balancing water uptake & loss ⑧ ↳ 6 O AP Biology freshwater balanced G saltwater = onrive 1 Managing water balance Hypotonic a cell in fresh water go to ell high concentration of water around cell in problem: cell gains water, swells & can burst example: Paramecium KABOOM! ex: water continually enters Paramecium cell solution: contractile vacuole pumps water out of cell ATP ATP plant cells turgid = full No problem, here cell wall protects from bursting AP Biology freshwater -Pumpout Pumping water out of cell Contractile vacuole in Paramecium - ATP AP Biology 2 Managing water balance Hypertonic I’m shrinking, a cell in salt water I’m low concentration of water shrinking! around cell waterout or cel problem:- cell loses water & can die - example: shellfish solution: take up water or pump out salt plant cells I will plasmolysis = wilt survive! can recover AP Biology saltwater 3 Managing water balance Isotonic That’s animal cell immersed in perfect! mild salt solution no difference in concentration of water between cell & environment problem: none no net movement of water flows across membrane equally, in both directions cell in equilibrium volume of cell is stable I could be better… example: blood cells in blood plasma slightly salty IV solution in hospital AP Biology balanced 1991 | 2003 Aquaporins Water moves rapidly into & out of cells evidence that there were water channels protein channels allowing flow of water across cell membrane Peter Agre Roderick MacKinnon AP Biology John Rockefeller Hopkins Do you understand Osmosis… En o B.05 M.03 M user more Cell (compared to beaker) hypertonic or hypotonic Beaker (compared to cell) hypertonic or hypotonic Which AP Biology way does the water flow? in or out of cell Any Questions?? AP Biology Ghosts of Lectures Past (storage) AP Biology 2007-2008 Diffusion through phospholipid bilayer What molecules can get through directly? fats & other lipids lipid What molecules can inside cell NOT get through NH3 salt directly? polar molecules H2O ions (charged) salts, ammonia sugar aa H2O large molecules outside cell starches, proteins AP Biology Membrane fat composition varies Fat composition affects flexibility membrane must be fluid & flexible about as fluid as thick salad oil % unsaturated fatty acids in phospholipids keep membrane less viscous cold-adapted organisms, like winter wheat increase % in autumn cholesterol in membrane O AP Biology Diffusion across cell membrane Cell membrane is the boundary between inside & outside… separates cell from its environment Can it be an impenetrable boundary? NO! IN OUT food waste carbohydrates OUT ammonia sugars, proteins salts amino acids CO2 IN lipids H2O salts, O2, H2O products AP Biology cell needs materials in & products or waste out Water Potential AP Biology Topic 2.8 = Water Potential Water potential is basically a way to measure how (psi) likely the water will move from one place to another. What are two variables that will influence osmosis and movement of water? *Solute Concentration S *Physical Pressure P P S Pressure Solute Potential Potential Loading… Pressure Potential P What would negative pressure look like? If you squeeze a water balloon, you're putting pressure on the water inside. And the more you squeeze it, the more pressure there is. Adding pressure, raises pressure Pressure potential. A positive value Potential Therefore, raising overall water P potential. Loading… Pressure Potential P 0 In an open container, the pressure potential is zero. 0 S Pressure Solute Potential Potential In an open container, the pressure potential is zero. In a open container with pressure potential = 0,↳ S Overall water potential is equal Solute to the solute potential. - Potential A solute is just a fancy word for anything that's dissolved in the water. For example, in plants solutes would be mineral ions and sugar. When there's a lot of solute in the water, the water molecules will S be attracted to the solute and are Solute less likely to move away from the Potential solutes. So, the more solute there is, the - lower the water potential (the less likely the water will move away from the solutes) Adding solute lowers the water potential, therefore it is a negative value. a negative value S Free water moves from regions of higher water potential to - regions of lower water potential if there is no barrier to flow. - Identify the region of Will water move into high water potential or out of the cell? (inside cell) more ser and wal low water potential in T Solutes have a -0.4 MPa this example. negative effect on (outside cell) water potential. -1.5MPa es wate ↑ Water flows from a high water potential to low water potential Water flows from a high water potential to low water potential e A U Where in this diagram is the water potential the highest? Loading… Where in this diagram is the B water potential the lowest? C 2 moter Water flows from a high water potential to low water potential A If the water potential inside the root is -0.6MPa, what is a possible value for the water potential within the soil? -0.1 MPa to -0.5 MPa B If the water potential inside the root is -0.6MPa, what is a C possible value for the water potential within the leaves? -0.7 MPa to -….. lastuter moster P S Pressure Solute Potential Potential The pressure potential is The solute potential is just the pressure that's how much the solutes pushing the water are affecting the water around. potential. 3 be T iC- - 0.0 nic S - A iCRT -i Solute ⑰ ionization How many molecules does Potential constant it dissociate into in water? i=1 i=2 NaC Na l +Cl - - S iCRT Solute Potential i constant ionization How many molecules does it dissociate into in water? i=1 i=2 C Molar NaC Concentration Na l +Cl 0.0M 0.2M - -RT S iCRT Solute Potential C 0.0M 0.2M 0.4M 0.6M 0.8M 1.0M Molar 0.35M Concentration 0.0M 0.2M cons R = Pressure constant - E 0.0831 (L*bars/mol*K) S T iCRT = Temp in Kelvin (K) (273.15 z + oC) Solute Potential C & 0.0 M 0.2 M 0.4M 0.6M 0.8M 1.0M Molar Concentration 0.0M 0.2M Potato cores are placed in sucrose solutions at room temperature (22oC) with various molar concentrations, and the percent change in mass is calculated for each solution. The data is graphed. From this data, it is determined that the molar concentration of the potato core is 0.32. What is the water potential of the sucrose solution? Solute potential =- iCRT = -(1)(0.32moles/L)(0.0831 L bars/mole K) (295K) = -7.8 bars As solute concentration increases (hypertonic), water P S potential becomes more The physical Water flowing negative. squeezing by osmosis Adding pressure, raises pressure potential - a positive value. = s More solutes inside the cell causes water to -3 flow in initially, however, as water flows in, it exerts a + pressure, and eventually = 0 S P Which area has a higher water potential: Intracellular region or extracellular region -1.0MPa Which area is hypertonic (assuming pressure potential = 0)? more Intracellular region or extracellular region -1.5MPa er Will the water flow into or out of this cell? Which area has a higher water potential: Intracellular region or extracellular region -1.0MPa How would you describe the extracellular lower & region: Hypotonic or Hypertonic? water -0.05MP Will the water flow into or out of this cell? a Morea How will this unicellular eukaryote osmoregulate? With a contractile vacuole pumping excess water out. Dou aen I. Endosymbiont Theory 2. Y o - e whyechondric 7 wit e prokaryo unloroe nave earyote eng dimp charac