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G.K -Recap of plants
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G.K -Parts of a plantH.12.K.5 Identify the purpose of national holidays and describe the people or events celebrated (e.g., Thanksgiving, Veteranās Day, Presidentās Day, Martin Luther King, Jr. Day) Eff..rs of ott.-PoFllat i What woLrld hoppen ro our colnrry i, it is ovetsp.pulored? When our counrry is ovā¬.-populdted, re @ ā¬xpā¬ri.nce rhā¬ foll.wirg: Food is our bdsic h@d. Whā¬n thā¬.Cs an ih.re.se ir populdtion it neans thar hore ,@d is iealed. It rheds ho .naJgh food, rrtrple irll srruggle wirh eddr othā¬r in ordeLro ā¬!'r- As o l!fllr, lhde rill be o f@d -- , ond ou, now]nert of on ihdiyiduol fron d c..tair - the move$eni o, on individudl our of o cerrain pla.e which help rā¬duce ihe populotion of th6t fr Arcihā¬. b.sic ned is w.ra. Wde. shorroge ocu.s when there is on ircreare of hu,nber of p@ple ro be $pptied. rn owr-popur.t d ore.s, woler is rdiorā¬d, Ir rEB rhoi supplies like ti,tWSS ond ,IWSI can'i $pply enoish worer. Do you hdve enough supply of sai.. in your oreo? Aside f.om food alld worer, shelier is olso ohe o, our inportant heeds. As the populoiion ihcre.!e!, building n.w hoLr!ā¬s or rheltā¬r is limit.i. To find solulion to this prcblā¬n, some goverihent og.ncies dnd orhs non{ovā¬Ihrehl offi.iofs (N6O) .onvefied sot@ ti.elields, du,np site. dnd nountcirlr inlo flbdivisions dnd relidentiols. Sut whot uould be ths effect o{ coMrtiig .i@fields to .6idā¬nri6l uits in our food supply? z , 2 Z Z :'", becouse there ore no enough space for prcpex garbage dkposol. ^s o rā¬sulr, sore peoPle lend to ihrow'their gorbdge onywh.fā¬. oorbdge baones brc{niry ond rursing ground of iEecrs and onidols ihot @se horm ro pe.ple. Dec.yiry garboge olso produces r,hpleaiant odor ard ehen burn if pmduces pois.nour qds @lled nelhohe As ihe populdtion incrā¬a3*, the 9d6.9e dso incraes. nris is T't ,,8 T H Wha you de living in on oa-populdi.d pla@, you moy oqaiae halrh prcblerns. Ir is be@@. the woi.r srpply is limit.d ihct will l..d you to poor hygi.ni. hobirs. In plo.4 like rhis, the surrouhdiigs naybe uniidy. o focrorthoi @uld oko cfFe.t your h4l'th. The common oilments rhot yd @uld oc$rire in ovesfDpllarā¬d ploces ore bEnchil is, o5l hnq. diqrrha and rube.culosis. 7,\ ,\\ \1" 6. Lnck of Herlrh sarvice llosi Pelple in 6n oM-populciā¬d 6ra 90 ro rubli. heilrh @trtas ond governhent hospirols be6u.e ii prcvides fr@ @Eulrorion oid los @sr rEdicdrions. A3 a ..suli, lhā¬sā¬ gow.nnenr dgā¬rciB b.@ne itud.4$re in mcetiig ihe n eds b..ou!ā¬ df ihsrfficiā¬nr funds. Lock of medicol personnel ,o odmaiisiā¬I is also s problen in mosr hosptols evā¬n rhere or. od.audtc supply of hedicire!. 7_ Do you how wlry rhe crimā¬ roiā¬ hexs ih becdurā¬ fiDre pe.ple o.e fnJrrctā¬d d@ ro sLfficiā¬.i naE io supp.rr their forniliG. ouf country inclY{ses? If is uh.mploymā¬ni dnd hdve no arinet .re u$dv grā¬{rer ia dn dq-popltdled ra whq. tl, , a, v, tlr I E. Air ard Watā¬r Pollutioh How dir be.o'nes pollutā¬d? I11ā¬ dir b@'nā¬s p.llurn be.4ne of rhe hormfolgoees thot ser. produ.4 by the fdcioriā¬s and vehicles. Itete {octories ond whi.l6 @ fuel ro run nochiB ond .JBin6. In ,hā¬ prc.ess, they give our Cdrboh Dioxide ond other ho.6ful gars.r such 6 Nittugei Oxide, Corbon l oioxide dnd Le.d iiio the oir. Do you know whot .ontdbute io ihe incrā¬asing number of whides qnd foctories? It is ihe inc.6e o, populdtion. As whdt I hove dis.!sse!, wirh a lihired sra.e 9@bd9e disposalie one of the problens thot .o!ld ise i, dh o!er-pop!,.tā¬d ploce. exn,jple ot thie orc rhosā¬ pelplā¬ livi,rg oh the raverside teid 'ro ,hrou, lheir gEr&ge Hde you seen 'th. P6si9 river or the Tulyahan river? Did you {ind it Whdr do you think i! ihe effā¬.t of ihis ih the.re4iures sho lives ih Ahothd f6do.s thal could.on rlbule to wdtd pollutioh dre oil s?ills, gorbqgā¬ fro,n boa, or ships ahd somā¬ ihdust.iol wosre. 9. Ite l@96f p4.enroge group. Individuols who orc this grclp. of olr popllarioh is compos.n of the working @pobla of s'rpporting ,heir fomilies nok !-up Though rhas group hol& the lojgeei percenroge of d. populaiion, rhis olso becomer one o{ oveFpopulored problā¬]ns bā¬4use there ore rc jobs awildble fo. oll of iha10. Erergy Shortdge ltere will be on energy shortdge iJ ihe populdtion incre63"l be.dise rhe d.,nand i. ā¬le.iriciry is high. Why is thai wh.n th. PoPqldion inclE.g, rhe d4ord in el4tricity is high? Ir B be.ouse there $,ould be 8to.e hdsat dnd blildirys to lighr ond nore el?riric oPPliohces ro run. rt.6rcznho!3.Ef+ed Whor is rhe grernho@ effā¬.r? In whoi say il c.uld offect c2 6re.hhG. effed is rhe wdrniltg of rhe drltlosphee. lvhen the 5un worft rhe.nrrh s1jrf.@, sone of rhe h@r goā¬J bo.k ro rhe ornos?herc. Air an the dtnDsphere which is C@boi Dioxid. ,rops ihe heot 6hd it mok6 the a.th very worm. As ihe populdtion coniinuou!|,l gtol4 , the gt@rl$use etfe.t b@res no.e visible. Ir is becaosu ,hera ore mo.e focrories snd whicl.s iha, produce wdstā¬s ond fuma5 which cduses more C{.bo. Diodde ir the ormosphere. As a rcsutt, ,herc eiould be nore h4, ,rop in the ornosphere uhich osk6 th. @ih nuch wornerIf this will hoppen continuously, ,hā¬ fish ih thā¬ ocah *ill diā¬, ricerields/f@mlands will dry too due to lhā¬ wcm clitnole 12. Destruction of rhe Ozone Loyer A5 whot you hove l@med lrheh you de in v5-6, rhot the qzore ldver is 'the proiecrive loyā¬. of the olnosPhdā¬. ft protects us {rom the homful effects of ultrdviolei rays of the su. Do you khow ,hot our Ozore lolā¬t q4. dQ4tt\!ci.d? Il olreadY hod holes lhai dllow the ulrroviolet rdys to .4dt ihe @rrh. How do6 this hdpPei? Does th. in rc$e of poPuldioh h@ā¬ sonething 'to do tr,lh ir? Yes, rhe I6i grov/irts PoPuldiion .odribuied o lot be@use 6 th' populotion incre3es, rhe u5e of refrigerd'tors, dā¬rosol lProvs 6nd pl4srics 6bo ihcre&s6. The sid producls coiiojn chemicol called Chlorofluorocdrbons (CFCS) which is mix wafh ihe dir in ihe ormosPherā¬. As o resulr. ihe hcrmfirl chernicol rā¬oches the Prolectiw ldver dnd lhrowh. hole in {hid ult@iolzi cahders aid cai4.ct3 ,F.*Y.iis hi!586$qā¬9.7,- Ho$ doas dcid rdin form? Is cid roii hdmful ro rEn? In the prcvious dis.ussions, yodtā¬ t.onā¬d rhd more vel .1e3 dnd fdctoriā¬s orā¬ necded fo het the iii:.e.siry number o{ P@Pla. Lefs now fihd af hd f@tot.iā¬s dnd vehicle! .ontribure in the forrEtion of ocid When foctories 6nd whi.ler give off woste gd..3 ,hot will ,nix on lhe noisture i. rhe oir, it will ihen Produ.e sulPhu.i. ocld dnd Nitri. o.id. 'Ihe clol,Jd folb will ,hā¬h obsorb rhese ccids ond ehei ihe clold f.lls os .oin, ih. ccid is ahady Pdrr of itU/ha d.id ftin falls oh lok"!, ,46 or ocan ihā¬ fish sill die d.d if h fdlls oh fopnlonds,lhe pldni. together oith the soil B desrroyed. When you inhole dir with Niiric acid, your blood will los. irs @pobilily io fonspori Oxygā¬h to your diffā¬.ai bodY Po.i3. ScieniisB include other rorns oJ dcidic prā¬cipiigrion. Thesā¬ drc nisi, Do you krcw ihot Nuclerr power slotionr Use .adiodctive ,ndie.ials in producirE fuels, yet, rhey do and those .odioactiw rndlqlotE gi\e otf radio'ting en.rgy thoi is harmrul 'to livirq thilEs. wlren rodiotion enlert ihe body ot living things it {ill srq rhere for o lorg ,eriod of ri'ne. Exonple fhe rodiqtion vG srilled to the c.m. Then rhe @rn will be aie by rhe chicken, the .odiotion o the c.rn 'rill also 'tronsfā¬r to the chi.kā¬n. Wha on individuol als ihe nat of the chickeh sith mdiarion, helshe rill .ko oblorb ihe rodi@.tirc mtaid that will destrcy hB/her .ā¬lls ond ruket hnn/hd si.r. Over-populoiion .on leld to food shoridgā¬, wdter shorroqe, housiB problā¬ms, qdrbogā¬ problā¬rs, lock of halrh sdi.e. tisa ol clit@ rote, oir ond woiā¬r pollution, uhanpl6ynat, eiergy 5horr69e, grenhoq3ā¬ efreci, desrruction o( th. ozo@ lat/e?, rci.l roi. olld e.lā¬d. watta SYI-1.D: Describe the structure and/ or function of subcellular components and organelles. ā
SYI-1.E: Explain how subcellular components and organelles contribute to the function of the cell. ā
SYI-1.F: Describe the structural features of a cell that allow organisms to capture, store, and use energy. ā
ENE-1.B: Explain the effect of surface area-to-volume ratios on the exchange of materials between cells or organisms and the environment. ā
ENE-1.C: Explain how specialized structures and strategies are used for the efficient exchange of molecules to the environment. ā
ENE-2.A: Describe the roles of each of the components of the cell membrane in maintaining the internal environment of the cell. ā
ENE-2.B: Describe the Fluid Mosaic Model of cell membranes. ā
ENE-2.C: Explain how the structure of biological membranes influences selective permeability. ā
ENE-2.D: Describe the role of the cell wall in maintaining cell structure and function. ā
ENE-2.E: Describe the mechanisms that organisms use to maintain solute and water balance. ā
ENE-2.F: Describe the mechanisms that organisms use to transport large molecules across the plasma membrane. ā
ENE-2.G: Explain how the structure of a molecule affects its ability to pass through the plasma membrane. ā
ENE-2.H: Explain how concentration gradients affect the ā
movement of molecules across membranes. ā
ENE-2.I: Explain how osmoregulatory mechanisms contribute to the health and survival of organisms. ā
ENE-2.J: Describe the processes that allow ions and other molecules to move across membranes. ā
ENE-2.K: Describe the membrane-bound structures of the eukaryotic cell. ā
ENE-2.L: Explain how internal membranes and membrane- bound organelles contribute to compartmentalization of eukaryotic cell functions. ā
EVO-1.A: Describe similarities and/or differences in compartmentalization between prokaryotic and eukaryotic cells. ā
EVO-1.B: Describe the relationship between the functions of endosymbiotic organelles and their free-living ancestral counterpartsChapter 22 Antihypertensive Drugs Hypertension Defined (JNC-8) Pharmacology Overview 7 main categories of drugs to treat HTN Adrenergic drugs (old friend) Angiotensin-converting enzyme (ACE) inhibitors Angiotensin II receptor blockers (ARBs) Calcium channel blockers (CCBs) Diuretics Vasodilators Direct renin inhibitors A. Adrenergic Drugs: 5 Subcategories and where they act A1. Adrenergic neuron blockers (central and peripheral)- we wonāt talk about this A2. Alpha1 receptor blockers (peripheral) A3. Alpha2 receptor agonists (central) A4. Beta receptor blockers (peripheral) A5. Combined Ī± and Ī² receptor blockers (peripheral) A2. Peripherally Acting Adrenergic Drug Alpha1 Blockers (weāve met these) Doxazosin, prazosin, alfuzosin Block alpha1-receptors which causes BP to decrease Reduces peripheral vascular resistance and BP by dilating both arterial and venous blood vessels Main Use: benign prostatic hyperplasia (BPH) Alpha1 Blockers REMEMBER Tamsulosin (Flomax)* is an Ī±1 blocker BUT *Tamsulosin is not used to control BP, just for BPH. A3. Centrally Acting Adrenergic Drugs Alpha 2 agonist Clonidine and methyldopa 1- Stimulate alpha2-adrenergic receptors. in the brain Decreases sympathetic outflow from the CNS which decreases NE production 2. Stimulate alpha2-adrenergic receptors in kidneys remember alpha 2 opposes alpha 1 Dilates peripheral blood vessels ā lowers peripheral resistance āĀ Results in decreased BP So ā¦.Clonidine (Catapres) Used primarily for its ability to decrease blood pressure in an urgent setting Also use in opioid withdrawal as previously discussed Oral (multiple times a day), and topical patch formulations Do not stop abruptly as it may lead to rebound hypertension In reality, Clonidine and methyldopa Not prescribed as first-line home antiHTN drugs High incidence of unwanted adverse effects: orthostatic hypotension, fatigue, and dizziness MIGHT be uses as adjunct drugs after other drugs have failed, in conjunction with other antiHTN such as diuretics A4. Adrenergic Drugs Selective Beta 1 Blockers Metoprolol, Atenolol Reduction of HR through Ī²1 receptor blockade (remember adrenergic blocking of this receptor???) HR results in BP Cause reduced secretion of renin = BP A4. Adrenergic Drugs Selective Beta1 Blockers Nebivolol (Bystolic) Uses: hypertension and HF Action: blocks Ī²1 receptors and produces vasodilatation, which results in a decrease in SVR High doses loses selectivity and blocks both Ī²1 and Ī²2 Less sexual dysfunction All BB- Do not stop abruptly; must be tapered over 1 to 2 weeks A4. Adrenergic Drugs NONSelective Beta Blockers Propranolol Acts equally on Ī²1 and Ī²2 Other uses include situational anxiety associated with public speaking, test taking As mentioned on previous slide, nebivolol at high doses becomes beta nonselective A5. Dual-Action Adrenergic Drugs Ī±1 and Ī² Receptor Blockers Dual antihypertensive effects of reduction in heart rate (beta1 receptor blockade) and vasodilation (alpha1 receptor blockade) Examples are carvedilol (common) and labetalol (not as common) A5. Dual-Action Adrenergic Drugs Ī±1 and Ī² Receptor Blockers Carvedilol (Coreg) Widely used drug that is well tolerated Uses: HTN, mild to moderate HF in conjunction with digoxin, diuretics, and ACE inhibitors Contraindications: severe bradycardia or unstable HF, bronchospastic conditions such as asthma, and various cardiac conduction problems Adrenergic Drugs Indications - HTN But also for Glaucoma (topical) BPH: doxazosin, prazosin, and terazosin (2 for 1) Management of severe HF when used with cardiac glycosides and diuretics Contraindications Acute HF- have to stabilize first MOAIs- yeah doesnāt everything interact with MAOIs? Peptic ulcers Severe liver/kidney disease Asthma (with beta blockers) Adrenergic Drugs: Adverse Effects Orthostatic hypotension 1st-dose syncope Rebound hypertension with abrupt discontinuation Most common: Dry mouth, drowsiness, constipation, sedation Interactions- always check for specific drug interactions Can cause additive CNS depression with alcohol, benzodiazepines, opioids Question #1 When administering an alpha-adrenergic drug for hypertension, it is most important for the nurse to assess the patient for the development of what response? Hypotension Hyperkalemia Oliguria Respiratory distress Answer A Hypotension This is a key point in patient education These drugs have strong vasodilating properties and may cause severe hypotension, especially at the beginning of therapy. B. Angiotensin-Converting Enzyme Inhibitors aka ACE Inhibitors or ACEi Large group of safe and effective drugs Currently are 10 ACEi Often used as first-line drugs for HF and hypertension May be combined with a thiazide diuretic, loop diuretic, or Calcium Channel Blocker (CCB) You need to understand the basics ACE Inhibitors: Review RAAS ACE converts angiotensin I, formed through the action of renin, to angiotensin II Angiotensin 2 is a potent vasoconstrictor and also induces aldosterone secretion by the adrenal glands Aldosterone stimulates sodium resorption (H20 follows Na Both act to raise BP which causes kidneys to reduce renin production ACEi= Great drug to treat HTN BUT contraindicated in pregnancy (2nd,3rd trimester due to fetal renal damage) and breastfeeding first few weeks after birth B. ACE Inhibitors - PRIL Lisinopril (Prinivil) super common, often the 1st drug Enalapril (Vasotec) also common Captopril (Capoten) great if liver disease present Benazepril (Lotensin) Fosinopril (Monopril) Perindopril (Aceon) Quinapril (Accupril) Ramipril (Altace) Trandolapril (Mavik) Primary Effects of the ACE Inhibitors Prevent Na (and H2O) resorption by inhibiting aldosterone secretion (volume reduction) (GO BACK TO RAAS DIAGRAM) blood volume decreases work of the heart preload, or the left ventricular end-diastolic volume which is important in HF ACE SUMMARY OF ACTIVITY 1) Prevent vasoconstriction caused by angiotensin 2 (2) Prevent aldosterone secretion ļØ less sodium and water resorption Cardioprotective Effects of ACEi They slow progression of left ventricular hypertrophy (ventricular remodeling) after MI so considered cardioprotective ACE inhibitors have been shown to decrease morbidity and mortality in patients with HF Renal Protective Effects of ACEi ACE inhibitors: reduce glomerular filtration pressure by volume reduction Cardiovascular drug of choice for patients with diabetes since it helps protect kidneys by reducing pressure. Sometimes used low dose for kidney protection with DM without HTN B. ACEi Enalapril (Vasotec) Only ACEi available in both oral and IV Enalapril IV does not require cardiac monitoring Oral enalapril: prodrug (metabolized in liver) Improves patientās chances of survival after an MI Reduces the incidence of HF B. ACEi Captopril (Capoten) Uses: prevention of ventricular remodeling after MI; reduce the risk of HF after MI Shortest half-lifeļØ Must be administered multiple times throughout the day so this limits its use Not a prodrug so good for patient with liver disease Question #2 A patient with diabetes has a new prescription for the ACE inhibitor lisinopril. She questions this order because her provider has never told her that she has hypertension. What is the best explanation for this order? The doctor knows best The patient is confused This medication has cardioprotective properties This medication has a protective effect on the kidneys for patients with diabetes Answer D ACE inhibitors have been shown to have a protective effect on the kidneys because they reduce glomerular filtration pressure. This property makes them the cardiovascular drug of choice for patients with diabetes. Question #3 A patient with a history of pancreatitis and cirrhosis is also being treated for hypertension. Which drug will most likely be ordered for this patient? Clonidine Prazosin Diltiazem Captopril Answer D Captopril Captopril is not a prodrug; therefore, it does not need to be metabolized by the liver to be effective. This is an advantage in patients with liver disease. ACE Inhibitors: Adverse Effects *Dry, nonproductive cough, which reverses when therapy is stopped. This is a class effect Dizziness- Note: First-dose hypotensive effect may occur Headache & Fatigue Possible hyperkalemia ** Angioedema: rare but potentially fatal Not safe in pregnancy-areĀ contraindicated during the second and third trimesters of pregnancyĀ because of increased risk of fetal renal damage C. Angiotensin II Receptor Blockers (ARB) Considered an alternative to ACEi Less likely to cause a dry cough and hyper K+ that is common with ACE inhibitors Angiotensin II Receptor Blockers: Mechanism of Action Go back to RAAS diagram! ARBs affect primarily 2 places 1. Vascular smooth muscle - blocks vasoconstriction 2. Adrenal gland -Selectively blocks the binding of Ang 2 to certain Ang 2 receptors inhibiting secretion of aldosterone Lowers volume retention and BP Angiotensin II Receptor Blockers -ARTAN Losartan (Cozaar)- very common Eprosartan (Teveten) Valsartan (Diovan) Irbesartan (Avapro) Candesartan (Atacand) Olmesartan (Benicar) Telmisartan (Micardis) Azilsartan (Edarbi) C. ARB Losartan (Cozaar) Beneficial in patients with HTN and HF Used with caution in patients with kidney or liver dysfunction and in patients with renal artery stenosis ***Not safe for breastfeeding women and should not be used in pregnancy (Cat C 1st trimester, Cat D 2nd-3rd trimester), potential fetal toxicity Appear to be equally effective for the treatment of hypertension and well tolerated ARBs less likely to cause cough and hyperK+ but can still happen Evidence that ARBs are associated with lower mortality after MI than ACE inhibitors Never take ACEi and ARBs at the same time* 5. Calcium Channel Blockers (CCB) Primary use: HTN, angina, some dysrhythmias Cause smooth muscle relaxation by blocking the binding of calcium to its receptors, preventing muscle contraction Results in: Relaxed blood vessels to the heart Decreased peripheral smooth muscle tone Decreased SVResistance Decreased BP E. Diuretics First-line antiHTN in JNC 8 guidelines Decreases fluid volume The results from diuresis: preload, Peripheral resistance Overall effect ļ Decreased workload of the heart and decreased BP Thiazide diuretics are the most commonly used diuretics for HTN Ie hydrochlorothiazide (HCTZ), chlorthalidone We will discuss diuretics further in the chapter on diuretics F. Vasodilators Directly relax arterial or venous smooth muscle (or both) Results in: Decreased SVR Decreased afterload Peripheral vasodilation Indicated for treatment of HTN May be used in combination with other drugs F. Vasodilators Hydralazine (Apresoline) Orally: routine cases of essential hypertension Injectable: hypertensive emergencies BiDil: specifically indicated as an adjunct for treatment of HF in African-American patients F. Vasodilators Sodium Nitroprusside (Nitropress) *Sodium nitroprusside and IV diazoxide are reserved for the management of hypertensive emergencies. Contraindications: severe HF, known inadequate cerebral perfusion (especially during neurosurgical procedures) F. Vasodilators Adverse Effects Hydralazine: dizziness, headache, tachycardia, edema, dyspnea, N/V/D, vitamin B6 deficiency, rash Sodium nitroprusside: hypotension, bradycardia, decreased platelet aggregation, rash G. Direct Renin Inhibitors Aliskirin (Tekturna) Blocks theĀ RASĀ pathway at the point of activation. Inhibiting renin production prevents the downstream production of Ang II (potent vasoconstrictor) Adverse effects: N/V, severe hypotension, hyponatremia, hyperkalemiaā¦ Contraindicated in patients with DM taking ACEi or ARB Miscellaneous Antihypertensives Eplerenone (Inspra) Newer class of drugs called selective aldosterone blockers (remember RAAS?) Reduces BP by blocking the actions of aldosterone at its corresponding receptors in the kidney, heart, blood vessels, and brain Indications: routine treatment of hypertension and for post-MI HF Contraindicated if serum potassium levels are high (above 5.6 mEq/L) A Special Form of HTN Treatment of Pulmonary Hypertension Sildenafil and Tadalafil Commonly used for erectile dysfunction Used for pulmonary hypertension but with different trade names Sildenafil: Revatio* (Viagra for ED) Tadalafil: Adcirca* (Cialis for ED)What is Electric Force? Electric force is just one of many types of forces in the world of physics. Forces are how and why things move, and can be explained by Newton's Laws of Motion. On the smallest scale, electric force is the resulting interaction between two charged particles. These charges can be either positive or negative. Larger objects can be charged by having an abundance of either of these particles, and therefore can create an electric force on a larger scale. Electric force is the reason why hair will sometimes stand up on its own and is also why we have electricity, allowing us to live in the modern world with lights and technology. Even out in nature electric force is present, as electric force causes lightning to strike. Electric force is fundamental to our everyday way of living. Reviewing Newton's Laws of Motion Newton's Laws of motion are the basic principles or ground rules that are applied all across physics. They describe how objects move and can be used to describe the interaction of charges. They are the following: An object in motion will stay in motion unless an external force is applied The force exerted on an object is equal to the mass times the acceleration of the object. ( ) Every force has an equal and opposite force Newton's laws explain how and why charged particles move. Since there is a force involved (e.g. electric force), particles will move around, which is explained by the first law. The second law describes how acceleration of charges can be calculated once the electric force is known. The third law explains how attractive and repulsive forces between charged objects are equal and opposite. Electric Force Examples and Types of Charge As previously mentioned, there are only two types of charges; positive and negative. Two like charges will repel (or move away from) each other, and two opposite charges will attract (or move towards) each other. In other words, two positive or two negative charges will repel, while a positive and a negative charge will attract. Opposite charges will attract while like charges will repel. Attraction versus Repelling Forces Notice how the forces acting upon each other are equal and opposite, as Newton's third law states. Both charges are exerting forces onto each other. Charges in Atoms An atom is made up of three types of particles; protons, neutrons, and electrons. Protons have a positive charge, neutrons have no charge, and electrons have a negative charge. There are no positive or negative charges smaller than protons and electrons. Objects on a larger scale result in an overall positive or negative charged due to an uneven distribution of protons to electrons. An atom consisting of more protons than electrons would be considered positive, and an atom with more electrons than protons would be considered negative. Protons are held close to the nucleus and are tightly bound to an atom, so it's difficult for protons to escape an atom. Electrons, on the other hand, are much further away from the nucleus of an atom. This makes it much easier for them to be removed from an atom. Electrons can leave or join atoms, making them positive or negative depending on the amount of protons. Similarly, for the bigger picture, overall materials and objects with more electrons than protons would be considered negative, and vice versa. Electric Force Examples Hair standing up: When hair is brushed, the hairbrush can strip electrons from hair strands, resulting in the hair being positively charged. This addition of electrons to the hairbrush in turn makes the hairbrush negatively charged. Since the hair is now positively charged, and like forces repel, hair strands will move away from each other, resulting in the hair standing up. Current electricity: All of our everyday technology is powered through current electricity, which is the consistent flow of electrons through conductive materials. This flow is caused by the electric force, as the electrons flow from a negative source to a positive source. Lightning: During a storm, it is common for an abundance of electrons to build up on the bottom of a cloud, making that part of the cloud negatively charged. Positive charges in the ground start to gather on the surface or even on tall objects such as trees as they are attracted towards the negatively charged undersides of clouds. Lightning strikes as a result of these charges becoming extremely built up. Lightning is caused by electric force Lightning Electric Force Equation: Coulomb's Law The magnitude of the electric force, or the amount of force in which objects repel or attract, depends on the distance between the two charged objects and the amount of charge each object carries. The electric force is stronger the closer together the two charges are, and weaker as the two charges move apart. Electric force is also stronger with more charge, and weaker with less charge. This effect on electric force is predictable, and is known as Coulomb's Law. It can be calculated using a mathematical equation, and the resulting magnitude of electric force is measured in Newtons. Coulomb's Law Electric force can be calculated using the following equation known as Coulomb's Law: In this equation, F is the electric force measured in newtons, K is a constant known as the electrostatic constant, and are charges one and two measured in coulombs, and is the radial distance in meters between the two charges. Since the distance is squared and on the denominator, the electric force drops off exponentially as charges move away from each other. This means that the Electric force is inversely proportional to distance. As charges move away from each other, the electric force between them gets smaller and smaller, until the force is negligible. The amount of charges are in the numerator of this equation, making the magnitude of the force larger with more charge. This means that the force is directly proportional to the amount of charge. When the charges are smaller, the amount of force will be smaller. When there is a lot of charge, the force will be much greater. When calculating the electric force using Coulomb's law, the resulting answer only gives the magnitude of the force and not the direction. In order to know the direction, you must know the types of charges. Once again, like forces repel, and unlike forces attract. It helps to draw a visual representation, or a free-body diagram, of the charges and forces acting upon them in order to understand the resulting force direction. Electric Field versus Electric Force An electric field is a direct result of an electric force. Its pure definition is electric force per unit charge, and can be thought of as a mapping of the force vectors. An electric field is present anytime there is an electric force. Therefore, when there are two or more charged particles, there is a surrounding electric field. The direction of the electric field is the direction a positive charge would flow if it were placed within the field. The electric field moves out from a positive charge and goes into a negative charge. Particles with unlike charges move towards each other, and their corresponding electric field lines move out from the positive charge and into the negative charge. The strength of the force at any given point can be seen through the spacing of the electric field lines. The electric force is strongest where the electric field lines are closest together, and weaker as these lines move apart. Like Coulomb's law expresses, electric field lines show how the electric force is strongest with a minimum distance between the two charges. Unlike charges will result in a repelling force, and the resulting electric field is a visual representation of this effect. Electric fields of two positive charges have the electric field moving out away from both of them. As with two negative charges, the field lines move in towards each negative. Lesson Summary An electric force is created when there are two or more charged particles or objects. These charges can be either positive or negative. Like charges will attract (move towards each other) while unlike charges will repel (move away from each other). As Newton's third law suggests, the forces acting upon each other are both equal and opposite. Electrons and protons within an atom are the two smallest types of charges there are. Electrons carry a negative charge while protons carry a positive charge. Electrons can be easily removed or added to atoms, making the overall charge positive or negative. Objects with more electrons than protons are negatively charged. Electric force is strengthened with increased charge and a shorter distance between the charges. This effect is known as Coulomb's law and can be calculated with the Coulomb's law equation. The magnitude of the force is measured in Newtons, and the direction can be determined by knowing whether the charges are attracting or repelling each other. An electric field is present wherever there is an electric force. The direction of this electric field is the direction a positive charge would flow if it where to be dropped in the field, which is from the positive to the negative.Covalent Molecules and Compounds Just as an atom is the simplest unit that has the fundamental chemical properties of an element, a molecule is the simplest unit that has the fundamental chemical properties of a covalent compound. Some pure elements exist as covalent molecules. Hydrogen, nitrogen, oxygen, and the halogens occur naturally as the diatomic (ātwo atomsā) molecules H2, N2, O2, F2, Cl2, Br2, and I2 (part (a) in Figure 3.1.1). Similarly, a few pure elements exist as polyatomic (āmany atomsā) molecules, such as elemental phosphorus and sulfur, which occur as P4 and S8 (part (b) in Figure 3.1.1). Each covalent compound is represented by a molecular formula, which gives the atomic symbol for each component element, in a prescribed order, accompanied by a subscript indicating the number of atoms of that element in the molecule. The subscript is written only if the number of atoms is greater than 1. For example, water, with two hydrogen atoms and one oxygen atom per molecule, is written as H2O. Similarly, carbon dioxide, which contains one carbon atom and two oxygen atoms in each molecule, is written as CO2. Covalent compounds that predominantly contain carbon and hydrogen are called organic compounds. The convention for representing the formulas of organic compounds is to write carbon first, followed by hydrogen and then any other elements in alphabetical order (e.g., CH4O is methyl alcohol, a fuel). Compounds that consist primarily of elements other than carbon and hydrogen are called inorganic compounds; they include both covalent and ionic compounds. In inorganic compounds, the component elements are listed beginning with the one farthest to the left in the periodic table, as in CO2 or SF6. Those in the same group are listed beginning with the lower element and working up, as in ClF. By convention, however, when an inorganic compound contains both hydrogen and an element from groups 13ā15, hydrogen is usually listed last in the formula. Examples are ammonia (NH3) and silane (SiH4). Compounds such as water, whose compositions were established long before this convention was adopted, are always written with hydrogen first: Water is always written as H2O, not OH2. The conventions for inorganic acids, such as hydrochloric acid (HCl) and sulfuric acid (H2SO4), are described elswhere. Note! For organic compounds: write C first, then H, and then the other elements in alphabetical order. For molecular inorganic compounds: start with the element at far left in the periodic table; list elements in same group beginning with the lower element and working up. Write the molecular formula of each compound. a. The phosphorus-sulfur compound that is responsible for the ignition of so-called strike anywhere matches has 4 phosphorus atoms and 3 sulfur atoms per molecule. b. Ethyl alcohol, the alcohol of alcoholic beverages, has 1 oxygen atom, 2 carbon atoms, and 6 hydrogen atoms per molecule. c. Freon-11, once widely used in automobile air conditioners and implicated in damage to the ozone layer, has 1 carbon atom, 3 chlorine atoms, and 1 fluorine atom per molecule. Solution: a. ā¢ A The molecule has 4 phosphorus atoms and 3 sulfur atoms. Because the compound does not contain mostly carbon and hydrogen, it is inorganic. ā¢ B Phosphorus is in group 15, and sulfur is in group 16. Because phosphorus is to the left of sulfur, it is written first. ā¢ C Writing the number of each kind of atom as a right-hand subscript gives P4S3 as the molecular formula. b. ā¢ A Ethyl alcohol contains predominantly carbon and hydrogen, so it is an organic compound. ā¢ B The formula for an organic compound is written with the number of carbon atoms first, the number of hydrogen atoms next, and the other atoms in alphabetical order: CHO. ā¢ C Adding subscripts gives the molecular formula C2H6O. c. ā¢ A Freon-11 contains carbon, chlorine, and fluorine. It can be viewed as either an inorganic compound or an organic compound (in which fluorine has replaced hydrogen). The formula for Freon-11 can therefore be written using either of the two conventions. ā¢ B According to the convention for inorganic compounds, carbon is written first because it is farther left in the periodic table. Fluorine and chlorine are in the same group, so they are listed beginning with the lower element and working up: CClF. Adding subscripts gives the molecular formula CCl3F. ā¢ C We obtain the same formula for Freon-11 using the convention for organic compounds. The number of carbon atoms is written first, followed by the number of hydrogen atoms (zero) and then the other elements in alphabetical order, also giving CCl3F. Write the molecular formula for each compound. a. Nitrous oxide, also called ālaughing gas,ā has 2 nitrogen atoms and 1 oxygen atom per molecule. Nitrous oxide is used as a mild anesthetic for minor surgery and as the propellant in cans of whipped cream. b. Sucrose, also known as cane sugar, has 12 carbon atoms, 11 oxygen atoms, and 22 hydrogen atoms. c. Sulfur hexafluoride, a gas used to pressurize āunpressurizedā tennis balls and as a coolant in nuclear reactors, has 6 fluorine atoms and 1 sulfur atom per molecule. Answer: a. N2O b. C12H22O11 c. SF6. Ionic Compounds The substances described in the preceding discussion are composed of molecules that are electrically neutral; that is, the number of positively-charged protons in the nucleus is equal to the number of negatively-charged electrons. In contrast, ions are atoms or assemblies of atoms that have a net electrical charge. Ions that contain fewer electrons than protons have a net positive charge and are called cations. Conversely, ions that contain more electrons than protons have a net negative charge and are called anions. Ionic compounds contain both cations and anions in a ratio that results in no net electrical charge. Note! Ionic compounds contain both cations and anions in a ratio that results in zero electrical charge.An ionic compound that contains only two elements, one present as a cation and one as an anion, is called a binary ionic compound. One example is MgCl2, a coagulant used in the preparation of tofu from soybeans. For binary ionic compounds, the subscripts in the empirical formula can also be obtained by crossing charges: use the absolute value of the charge on one ion as the subscript for the other ion. This method is shown schematically as follows: Crossing charges. One method for obtaining subscripts in the empirical formula is by crossing charges. When crossing charges, it is sometimes necessary to reduce the subscripts to their simplest ratio to write the empirical formula. Consider, for example, the compound formed by Mg2+ and O2ā. Using the absolute values of the charges on the ions as subscripts gives the formula Mg2O2:Polyatomic Ions Polyatomic ions are groups of atoms that bear net electrical charges, although the atoms in a polyatomic ion are held together by the same covalent bonds that hold atoms together in molecules. Just as there are many more kinds of molecules than simple elements, there are many more kinds of polyatomic ions than monatomic ions. Two examples of polyatomic cations are the ammonium (NH4+) and the methylammonium (CH3NH3+) ions. P. The method used to predict the empirical formulas for ionic compounds that contain monatomic ions can also be used for compounds that contain polyatomic ions. The overall charge on the cations must balance the overall charge on the anions in the formula unit. Thus, K+ and NO3ā ions combine in a 1:1 ratio to form KNO3 (potassium nitrate or saltpeter), a major ingredient in black gunpowder. Similarly, Ca2+ and SO42ā form CaSO4 (calcium sulfate), which combines with varying amounts of water to form gypsum and plaster of Paris. The polyatomic ions NH4+ and NO3ā form NH4NO3 (ammonium nitrate), a widely used fertilizer and, in the wrong hands, an explosive. One example of a compound in which the ions have charges of different magnitudes is calcium phosphate, which is composed of Ca2+ and PO43ā ions; it is a major component of bones. The compound is electrically neutral because the ions combine in a ratio of three Ca2+ ions [3(+2) = +6] for every two ions [2(ā3) = ā6], giving an empirical formula of Ca3(PO4)2; the parentheses around PO4 in the empirical formula indicate that it is a polyatomic ion. Writing the formula for calcium phosphate as Ca3P2O8 gives the correct number of each atom in the formula unit, but it obscures the fact that the compound contains readily identifiable PO43ā ions.Summary ā¢ There are two fundamentally different kinds of chemical bonds (covalent and ionic) that cause substances to have very different properties. ā¢ The composition of a compound is represented by an empirical or molecular formula, each consisting of at least one formula unit.Contributors The atoms in chemical compounds are held together by attractive electrostatic interactions known as chemical bonds. Ionic compounds contain positively and negatively charged ions in a ratio that results in an overall charge of zero. The ions are held together in a regular spatial arrangement by electrostatic forces. Most covalent compounds consist of molecules, groups of atoms in which one or more pairs of electrons are shared by at least two atoms to form a covalent bond. The atoms in molecules are held together by the electrostatic attraction between the positively charged nuclei of the bonded atoms and the negatively charged electrons shared by the nuclei. The molecular formula of a covalent compound gives the types and numbers of atoms present. Compounds that contain predominantly carbon and hydrogen are called organic compounds, whereas compounds that consist primarily of elements other than carbon and hydrogen are inorganic compounds. Diatomic molecules contain two atoms, and polyatomic molecules contain more than two. A structural formula indicates the composition and approximate structure and shape of a molecule. Single bonds, double bonds, and triple bonds are covalent bonds in which one, two, and three pairs of electrons, respectively, are shared between two bonded atoms. Atoms or groups of atoms that possess a net electrical charge are called ions; they can have either a positive charge (cations) or a negative charge (anions). Ions can consist of one atom (monatomic ions) or several (polyatomic ions). The charges on monatomic ions of most main group elements can be predicted from the location of the element in the periodic table. Ionic compounds usually form hard crystalline solids with high melting points. Covalent molecular compounds, in contrast, consist of discrete molecules held together by weak intermolecular forces and can be gases, liquids, or solids at room temperature and pressure. An empirical formula gives the relative numbers of atoms of the elements in a compound, reduced to the lowest whole numbers. The formula unit is the absolute grouping represented by the empirical formula of a compound, either ionic or covalent. Empirical formulas are particularly useful for describing the composition of ionic compounds, which do not contain readily identifiable molecules. Some ionic compounds occur as hydrates, which contain specific ratios of loosely bound water molecules called waters of hydration.Can you create an evaluation using this information PHONETICS VS. PHONOLOGY Whereas phonetics is the study of sounds that occur in language, phonology is the study of how these sounds are organized and how they function in language. It uses the classifications of sounds derived from phonetics to describe and analyze how sounds occur in speech. STRUCTURALIST PHONEMICS STRUCTURALIST PHONEMICS As linguists began to study sounds in fine detail, they recognized increasingly complex aspects of phonetic organization. For example, the sound /p/ appears in different varieties in English. STRUCTURALIST PHONEMICS One of the varieties of /p/ is indicated by [ph]. This sound is produced with an accompanying puff of air called aspiration, as in the words āpill,ā and āpeace.ā Another sound, indicated by [pā¢], is produced when there is little or no aspiration; this sound occurs in a word like āspill.ā A third major variety for the /p/ sound is the unreleased [pā ], which may occur at the end of a word like āstop.ā To deal with these variations for the /p/ sound, the structuralists suggested the existence of an abstract unit which they termed a phoneme. STRUCTURALIST PHONEMICS A phoneme was defined by the structuralists as an abstract phonological unit that represents a class of real sounds, termed the allophones of a phoneme. The phoneme /p/ in English, then, is represented by the allophones [ph], [pā¢], and [pā ]. STRUCTURALISTS: MINIMAL PAIRS How do we know what these abstract units of sound called phonemes are? In order to find the phonemes of a language, the structuralists developed the concept of the minimal pair, defined as any two words that: a) Contain the same number of segments b) Differ in meaning c) Exhibit only one phonetic difference. STRUCTURALISTS: MINIMAL PAIRS In practical terms, phonemes distinguish meanings; and a phoneme can also be defined as the smallest meaning-distinguishing unit of sound. For instance, the words āpinā /pÉŖn/ and ābinā /bÉŖn/ mean different things, and the only one difference in these words occurs in the initial sounds. STRUCTURALISTS: MINIMAL PAIRS By using the concept of a minimal pair, we can determine that the three variations of the /p/ sound do not represent three phonemes. Certainly, it is possible to pronounce the word cap with either an aspirated [ph ] or unreleased [pā ]; however, the two forms [kƦph ] and [kƦpā ] are not a minimal pair, even though they involve different sounds, because they are identical in meaning. STRUCTURALISTS: FREE VARIATION The two forms [kƦph ] and [kƦpā ] are, therefore, said to exhibit free variation: that is, the pronunciation may vary without signifying a change in meaning. In other words, we may conclude that the unreleased [pā ] and the aspirated [ph ] are not representations of different phonemes in English; they are, in fact, allophones of one phoneme, /p/. STRUCTURALISTS: COMPLEMENTARY DISTRIBUTION When phonemes have more than one allophone in a language, the allophones are said to be in complementary distribution. Complementary distribution means that the allophones of a phoneme occur in different phonetic environments (that is, with different sounds surrounding them). TRANSFORMATIONAL- GENERATIVE PHONOLOGY TRANSFORMATIONAL-GENERATIVE PHONOLOGY Transformational-generative phonology is a relatively recent development in linguistic theory. Chomsky launched Transformational-Generative Grammar in 1957, but the earliest studies within this framework were largely concerned with syntax. A decade later, the first comprehensive transformational-generative treatment of English phonology appeared: Chomsky and Halleās The Sound Pattern of English (1968). TRANSFORMATIONAL-GENERATIVE PHONOLOGY Transformational-generative phonologists strongly oppose the structuralistsā phonemic level. They replace this level by a series of rules that directly relate underlying representations to observed phonetic representations. The central mechanisms in transformational-generative phonology, then, are underlying representations and phonological rules. PHONOLOGICAL RULES A rule is an operational statement in which some linguistic entity is modified, resulting in a new linguistic entity. Rules may add elements, remove elements, or change elements. By using phonological rules, linguists attempt to demonstrate that there is order in linguistic phenomena and that linguistic patterns are systematic. PHONOLOGICAL DERIVATION A phonological derivation is an operation that begins with an underlying representation and, through the application of a set of specific rules, yields the actual sound the speaker produces. The representation of a phonological rule has the following general appearance. /A/ ā [B] / C āAā changes to āBā under condition āCā PHONOLOGICAL RULE ā EXAMPLE In most Southern dialects, the word ten is pronounced like the word tin. This is not an isolated fact, for den is pronounced like din and Ben is pronounced like bin, and so on. This very general fact can be represented by the phonological rule: /É/ ā [I] / ___ [n] den /dÉn/ ā /dIn/ Ben /bÉn/ ā /bIn/ ten /tÉn/ ā /tIn/ /É/ ā [I] / ___ [n] - high - low - tense + front + high - tense + front + sonorant + anterior + coronal - continuant NOTATIONAL DEVICES IN PHONOLOGICAL RULES The statement of phonological rules can be complex, and linguists have developed several notational devices for writing them. Often, the following symbols will be necessary for stating the conditions under which rules apply: # indicates a word boundary + indicates an intraword boundary $ indicates a syllable boundary UNDERLYING REPRESENTATIONS AND RELATED ISSUES The transformational-generative description of phonology relates underlying representations to phonetic representations by rules. This can be represented in a simple example: In English, there are certain pairs of words like sign / signature, and malign / malignant that exhibit a regular alternation in their phonetic representations: [g] is present in the second member of the pairs but absent in the first member. UNDERLYING REPRESENTATIONS AND RELATED ISSUES To explain the relatedness of words such as sign / signature, we could claim that the underlying representation of the segment in all such pairs is /g/ and that a rule operates to delete /g/ before syllable-final nasals. Thus, the rule ā/g/ is deleted before syllable-final nasalā would appear formally as: + voice - anterior āā
____ [+ nasal] $ - coronal UNDERLYING REPRESENTATIONS AND RELATED ISSUES On the left-hand side of the arrow, we place the features needed to uniquely specify /g/ among the consonants; that is, no other consonant has the features [+ voice], [- anterior], and [- coronal]. The symbols ā mean that the sound /g/ changes to nothing or more properly ā/g/ is deleted.ā The horizontal line following the slash mark refers to the position of /g/ - namely, before a segment that is [+nasal]. Finally, this [+nasal] segment occurs before a syllable boundary, as indicated by $. A less formal way of writing this rule would be: /g/ ā / _ [+nasal] $ Notice that this rule also helps describe such alternations as phlegm/phlegmatic and paradigm/paradigmatic. Application Activity: Think of other words in which this rule can be applied. Write the sound segments to prove /g/ is deleted. Another example is the process through which the prefix meaning ānotā is added to words. This prefix alternates among the forms /Im/, /In/, and /IÅ/, depending on the point of articulation of the initial segment of the following word. -If the segment begins in the extreme front part of the mouth (labials), the form is /Im/, as in improper. -If the segment begins in the extreme back part of the mouth (velars), the form is /IÅ/, as in incomplete. -If the segment begins in the mid-region of the mouth (all other sounds), the form is /In/, as in indecent. *Exceptions:Words beginning with /r/ or /l/. Analyze the Word āin + complete,ā for example. /n/ ā [Å] / __ [k] - continuant - continuant - continuant + sonorant ā + sonorant - sonorant + anterior - anterior - strident + coronal - coronal - coronal + tense THE VELAR SOFTENING RULE Still another example of alternation in English is found in pairs of words like āelectric / electricity,ā in which the segments /k/ and /s/ alternate. /k/ changes to [s] only before non- low, front vowels. THE VELAR SOFTENING RULE /k/ ā [s] / __ - continuant + continuant - strident ā - sonorant V - anterior + anterior - low - coronal + coronal - back