Hello, i have 20 multiple choice questions for Biology. its an exam. once i open it i have 2 hours to complete. do you have an expert who can assist me. its due tomorrow
1. Hierarchy of Ecological Organizational Levels: individual <>< community="">< ecosystem="">< biosphere="" each="" higher="" level="" includes="" all="" of="" the="" levels="" underneath="" it.="" populations="" are="" made="" up="" of="" individuals="" and="" communities="" are="" made="" up="" of="" several="" populations,="" etc.="" review="" this="" on="" pgs="" 10-12="" in="" the="" openstax="" textbook.="" we="" will="" be="" returning="" to="" this="" topic="" in="" week="" 7="" when="" we="" discuss="" ecology.="" ="" 2.="" ="" control="" group="" vs.="" experimental="" group:="" control="" groups="" are="" an="" important="" part="" of="" an="" experiment.="" the="" control="" group="" is="" sometimes="" referred="" to="" as="" the="" experimental="" control.="" this="" is="" the="" group="" that="" does="" not="" get="" the="" independent="" variable="" and="" is="" used="" as="" a="" baseline="" or="" comparison="" for="" your="" experimental="" group="" that="" does="" get="" the="" independent="" variable.="" see="" the="" scientific="" method="" tutorial="" to="" review="" this="" under="" item="" 4,="" the="" scientific="" method.="" ="" 3.="" ="" energy="" flows="" while="" matter="" (nutrient,="" molecules,="" atoms)="" is="" recycled:="" this="" is="" a="" recurring="" theme="" in="" biology.="" energy="" is="" not="" made="" up="" of="" matter,="" so="" it="" can="" only="" be="" transferred="" or="" changed="" from="" one="" form="" to="" another="" (light="" to="" heat="" or="" chemical="" energy="" to="" heat="" and="" work).="" matter="" on="" the="" other="" hand="" has="" mass,="" is="" composed="" of="" atoms,="" and="" takes="" up="" space.="" atoms="" can="" recombine="" to="" form="" different="" molecules,="" and="" are="" continually="" reused="" in="" living="" systems.="" ="" 4.="" ="" independent="" vs.="" dependent="" variables:="" the="" independent="" variable="" is="" what="" you="" are="" manipulating="" or="" changing="" in="" the="" experiment,="" while="" the="" dependent="" variable="" is="" the="" outcome="" you="" are="" observing.="" see="" the="" scientific="" method="" tutorial="" to="" review="" this="" under="" item="" 4,="" the="" scientific="" method.="" you="" can="" also="" watch="" this="" short="" movie="" on scientific="" variables.="" ="" 5.="" ="" subatomic="" particles="" and="" properties="" of="" atoms:="" here="" are="" a="" few="" things="" to="" remember="" about="" subatomic="" particles="" and="" atoms.="" first,="" the="" number="" of="" electrons="" in="" an="" atom="" equals="" the="" number="" of="" protons="" (atoms="" are="" neutral="" so="" the="" number="" of="" negatively="" charged="" particles,="" electrons,="" is="" the="" same="" as="" the="" number="" of="" positively="" charged="" particles,="" protons).="" the="" atomic="" number="" is="" equal="" to="" the="" number="" of="" protons="" in="" an="" atom.="" atomic="" mass="" is="" equal="" to="" the="" number="" of="" protons="" plus="" the="" number="" of="" neutrons="" (which="" have="" no="" charge).="" protons="" and="" neutrons="" are="" found="" in="" the="" nucleus="" or="" core="" of="" the="" atom="" while="" electrons="" orbit="" around="" the="" atom’s="" nucleus.="" review="" pgs.="" 28-29="" in="" the="" openstax="" textbook.="" ="" 6.="" ="" number="" of="" electrons="" in="" electron="" shells:="" the="" first="" electron="" shell="" can="" hold="" up="" to="" two="" electrons,="" while="" the="" second="" and="" third="" can="" each="" hold="" 8.="" the="" outermost="" shell="" of="" electrons="" is="" call="" the="" valence="" electron="" shell,="" and="" the="" electrons="" here="" are="" the="" ones="" that="" can="" for="" chemical="" bonds.="" this="" is="" briefly="" discusses="" on="" pg="" 31="" in="" the="" openstax="" textbook.="" ="" 7.="" ="" the="" difference="" between="" ionic,="" covalent="" and="" hydrogen="" bonds:="" chemical="" bonds="" are="" discussed="" on="" pgs.31-33="" in="" the="" openstax="" textbook.="" understanding="" the="" differences="" among="" these="" types="" of="" chemical="" bonds="" is="" important="" for="" understanding="" the="" properties="" of="" biological="" macromolecules="" as="" well="" as="" the="" properties="" of="" cell="" membranes="" and="" membrane="" transport.="" remember="" that="" hydrogen="" bonds="" are="" responsible="" for="" the="" 3d="" shape="" of="" nucleic="" acids="" and="" proteins.="" you="" can="" also="" look="" at="" my="" chemical="" bond="" cheat="" sheet="" found="" in="" the="" week="" 1="" course="" content="" area="" of="" our="" leo="" classroom.="" ="" 8.="" ="" emergent="" properties:="" this="" is="" a="" property="" that="" emerges="" or="" comes="" to="" exist="" only="" when="" component="" subparts="" are="" joined="" together="" in="" a="" certain="" way="" and="" that="" does="" not="" exist="" in="" any="" of="" the="" subparts="" alone.="" any="" one="" of="" the="" subcomponents="" of="" a="" cell="" (dna,="" cell="" membrane,="" cytoplasm,="" etc.)="" is="" not="" alive,="" but="" when="" they="" are="" joined="" together,="" a="" cell="" is="" able="" to="" live.="" ="" 9.="" ="" the="" properties="" of="" water:="" there="" are="" several="" unique="" properties="" of="" water="" that="" make="" it="" essential="" for="" life="" and="" living="" organisms.="" they="" are="" discussed="" on="" pgs.="" 34-37="" in="" the="" openstax="" textbook.="" review="" these="" properties.="" also,="" there="" is="" a="" nice="" summary="" provided="" here: the="" properties="" of="" water.="" ="" 10.="" hierarchy="" of="" atoms="" to="" organism:="" remember="" that="" subatomic="" particles="">< atoms="">< molecules="">< organelles="">< cells="">< tissues="">< organs="">< organ="" systems="">< organisms/individuals.="" you="" could="" finish="" this="" is="" what="" is="" listed="" in="" item="" 1="" above.="" again,="" refer="" to="" pgs="" 10-12="" in="" the="" openstax="" textbook="" to="" review="" this.="" the="" point="" is="" that="" larger,="" more="" complex="" things="" are="" composed="" of="" simpler,="" smaller="" things.="" ="" 11.="" the="" charge="" of="" atoms="" (when="" they="" become="" ions):="" when="" atoms="" gain="" or="" lose="" a="" valence="" electron="" they="" become="" charged="" atoms,="" which="" are="" called="" ions.="" this="" was="" discussed="" briefly="" on="" pg.="" 31="" in="" the="" openstax="" textbook.="" here="" are="" few="" rules="" to="" help="" you="" determine="" what="" type="" of="" ion="" an="" atom="" will="" become.="" all="" atoms="" in="" column="" 17="" of="" the="" periodic="" table="" contain="" 7="" electrons="" in="" their="" valence="" shell;="" therefore,="" they="" will="" gain="" one="" electron="" to="" complete="" their="" shell="" giving="" them="" a="" charge="" of="" -1.="" they="" become="" anions.="" all="" atoms="" in="" column="" 16="" of="" the="" periodic="" table="" contain="" 6="" electrons="" in="" their="" valence="" shell;="" therefore,="" they="" will="" gain="" two="" electrons="" to="" complete="" their="" shell="" giving="" them="" a="" charge="" of="" -2.="" they="" become="" anions.="" all="" atoms="" in="" column="" 1="" of="" the="" periodic="" table="" contain="" 1="" electrons="" in="" their="" valence="" shell;="" therefore,="" they="" will="" lose="" one="" electron="" to="" empty="" their="" shell="" giving="" them="" a="" charge="" of="" +1.="" they="" become="" cations.="" all="" atoms="" in="" column="" 2="" of="" the="" periodic="" table="" contain="" 2="" electrons="" in="" their="" valence="" shell;="" therefore,="" they="" will="" lose="" those="" electrons="" to="" empty="" their="" shell="" giving="" them="" a="" charge="" of="" +2.="" they="" become="" cations.="" what="" happens="" in="" the="" middle="" of="" the="" periodic="" table="" gets="" to="" be="" confusing.="" for="" our="" purposes,="" you="" should="" know="" that="" carbon="" atoms="" have="" 4="" electrons="" in="" their="" valence="" shell="" and="" carbon="" atoms="" for="" only="" covalent="" bonds="" not="" ionic="" bonds.="" ="" 12.="" cells="" are="" the="" fundamental="" unit="" of="" life:="" there="" is="" no="" getting="" around="" this="" one.="" the="" cell="" is="" the="" first="" organization="" unit="" or="" hierarchical="" level="" where="" the="" property="" of="" life="" exists.="" memorize="" this!="" the="" cell="" is="" the="" basic="" unit="" of="" life.="" ="" 13.="" definition="" of="" homeostasis:="" we="" will="" be="" returning="" to="" the="" topic="" of="" homeostasis="" in="" upcoming="" weeks.="" we="" define="" homeostasis="" as="" the="" tendency="" of="" organisms="" and="" cells="" to="" maintain="" stable="" internal="" conditions.="" the="" term="" comes="" from="" the="" greek="" words="" homeo="" (same,="" alike)="" and="" stasis="" (standing).="" this="" will="" be="" further="" discussed="" in="" chapter="" 16="" of="" the="" openstax="" textbook.="" ="" 14.="" common="" traits="" of="" carbon,="" oxygen,="" nitrogen="" and="" hydrogen="" atoms:="" these="" atoms="" all="" have="" unpaired="" valence="" electrons="" which="" allow="" them="" to="" readily="" for="" bonds="" with="" each="" other="" as="" well="" as="" other="" atoms.="" these="" are="" important="" atoms="" in="" biology.="" ="" 15.="" polarity="" and="" electronegativity:="" electronegativity="" (the="" ability="" of="" an="" atom="" to="" draw="" shared="" electrons="" closer="" to="" itself.="" strongly="" electronegative="" atoms="" bonded="" to="" weakly="" electronegative="" hydrogen="" atoms,="" in="" a="" molecule,="" result="" in="" hydrogen="" bonding.="" the="" most="" important="" strongly="" electronegative="" elements="" in="" biological="" systems="" are="" oxygen="" and="" nitrogen)="" is="" the="" property="" of="" an="" atom="" that="" allows="" for="" the="" formation="" of="" polar="" covalent="" bonds.="" hydrogen="" bonding="" forms="" between="" two="" polar="" molecules.="" revisit="" pg.="" 32="" and="" 33="" in="" the="" openstax="" textbook.="" ="" 16.="" the="" characteristics="" of="" life:="" this="" too="" is="" on="" you="" cannot="" get="" around.="" memorize="" the="" 8="" characteristics="" of="" life="" found="" on="" pgs.="" 6-9="" in="" the="" openstax="" textbook.="" ="" 17.="" solutes="" vs.="" solvents:="" solvents="" are="" the="" majority="" of="" the="" solution="" (what="" a="" solute="" is="" dissolved="" into).="" solutes="" are="" the="" component(s)="" that="" make="" up="" less="" of="" the="" solution.="" you="" make="" a="" salt="" water="" solution.="" water="" is="" the="" solvent="" while="" sodium="" chloride="" (nacl),="" table="" salt,="" is="" the="" solute.="" this="" was="" mentioned="" briefly="" on="" pg.="" 36="" because="" water="" is="" an="" excellent="" solvent.="" chapter="" 3="" of="" the="" openstax="" textbook="" will="" go="" into="" more="" detail.="" ="" 18.="" isotopes:="" isotopes="" are="" different="" forms="" of="" the="" same="" atom="" that="" have="" identical="" numbers="" of="" protons,="" but="" different="" numbers="" of="" neutrons.="" the="" isotope="" with="" the="" non-typical="" number="" of="" neutrons="" is="" radioactive.="" see="" pg.="" 29="" in="" the="" openstax="" textbook="" to="" review.="" ="" 19.="" the="" ph="" scale:="" review="" pgs.="" 37-38="" in="" the="" openstax="" textbook.="" acids="" donate="" h+="" ions="" when="" dissolved="" in="" water="" while="" bases="" donate="" oh-="" ion="" when="" dissolved="" in="" water.="" the="" ph="" scale="" ranges="" from="" 1-14.="" if="" the="" ph="" is=""><7 the="" substance="" is="" an="" acid.="" if="" the="" ph="" is="">7 the substance is a base. A pH of 7 is neutral because it contains equal numbers of H+ and OH- ions. Remember that the pH scale is logarithmic meaning that there is a 10-fold different in the number of hydrogen atoms between each pH unit. If you compare a solution at pH 4 and a solution at pH 2, the pH 2 solution has 100 times as many hydrogen atoms (these solutions differ by 2 pH units, so there is a 102 = 100 fold difference in the number of hydrogen atoms). Likewise, when comparing two bases at pH 8 and 10, the solution at pH 8 has 100 times more hydrogen ions as compared to the pH 10 solution. 20. The Purpose of Experiments: The purpose of experimentation is to disprove a hypothesis. See pg 26 in the OpenStax textbook. 21. The Hierarchy of the Linnean Taxonomic Classification of Organisms: See pgs. 12-13 in the OpenStax textbook. Remember that the most broad classification is the Domain and the most narrow is the species. The order is as follows: Domain > Kingdom > Phylum > Class > Order > Family > Genus > Species. 22. Natural Law vs. Scientific Theory: See pg. 18 of the OpenStax textbook to review these definitions. A Natural Law is a summary of observed behaviors in nature (think the Law of Gravity). A Scientific Theory is a proposed explanation or working model for why a behavior occurs. 23. Prokaryotic vs. Eukaryotic Cells: These terms are introduced on mg. 10 in the OpenStax textbook. They will be covered more in depth in Chapter 3. Remember that the biggest difference between the two is that Eukaryotic cells contain a nucleus and membrane bound organelles while prokaryotic cells do not. 24. Define pH: pH is the measurement of the acidity of a solution. Acids are solution where the concentration of hydrogen ions (H+) is greater than the concentration of hydroxide ions (OH-). This of pH as “parts hydrogen”. 25. Litmus paper: This is one way in which we can determine whether or not a solution is acidic or basic. Red litmus paper will turn blue (blue for base) when put in a base. Red litmus paper stays red in an acid. Blue litmus paper turns red when put in an acid. 26. Buffers: Buffers are solutions that contain substances in them that allow the pH of the solution to be maintained when small amount of acids or bases are added to them. Typically, buffers can either give off a hydrogen ion to “buffer” the solution if a base is added, and they can give off a ion that will bind up excess hydrogen ions to “buffer” the solution if an