again hopefully what's up you Penguins hi so I'm Mrs Jones and I figured I would come live and I would go over unit one with you um so sit tight because I think for the next hour or so um we're going to go over unit one um and in case you don't know I'm from uh AP biop Penguins so if you uh are looking for a free review just go check out AP biop Penguins on Instagram and there's Daily Review on there okay um and so since you're sitting in this live stream um to me that means that you're interested in AP Bio and that you are taking AP Bio um and so I believe that AP Bio students are dressed for Success um and that you're penguin so now that you are in here and you're doing this live you are a penguin now so you are one of my AP Bio Penguins um so couple resource reminders um so since you're in here you probably already know about all these resources but in case you're watching the recording later um I figure you might want to know about these resources um so number one I do a daily review on Instagram so uh starting on February 1st I have been posting every day Monday through Friday um review questions and so I do a topic a day um which allows you to be able to review for the AP exam um I also have a 340 uh 374 page review guide um posted onto my Weebly um which that is at the bottom of the page it's ww. apop penguin. weebly.com literally just Google AP biop Penguins um and you can easily um see it okay um ALS so I it's called frq Friday but um so once a week I usually will record um free response videos so I'll pick a video that um or topic that my students are currently learning um and we will go through the free response I go through what the examplar looks like I go through the scoring guidelines and then Conant tips and tricks um for those exam questions um and then there's 120 quizzes games so I've got games for each of the topics as well as I've got um games for each of the ceds so all of the topics in the CED I've got there ready to go um and then I've also got review Powerpoints and so if you go check out that website. AP biop with.com there's a ton of resources for you I do not expect you to use all the resources um but it's there for you if you would need those resources um and this is live so you're welcome to ask questions in the chat um and I can answer them as I see them um or I might just answer them at the end when we do our Q&A um so we're sorry wrong screen uh so today's plan we're doing unit one so that includes our macromolecules that includes water properties um I have a couple practice questions in there and then I have some time for us to do some Q&A um so real quick the macro molecules there are four different macromolecules that we need to know about and these tend to kind of loop in and out for the entire year you're going to be using these macro molecules all year long um so the first one we have is carbohydrates we know that that is our sugars we've got our proteins that are going to have structure ual support um as well as they do some motor actions they do for enzymes like proteins are the workhorses of our cells um we've got nucleic acid which is where the genetic material is as well as our transcription and our translation well not translation but I guess it's us real um and then of course we've got our lipids so let's first focus on carbohydrates and again if you have questions as we go through this you're welcome to throw them into the chat um so these macromolecules you need to have a overall picture of them and you need to know about the different structures of them and the bonding of them okay hey Melanie from the after recap so if y'all are not currently following Melanie she's doing um a countdown to the AP exam with a hundred uh either tips tricks um or things about the exam you need to know so definitely go follow the absolute recap on um Tik Tok and Instagram plus she's got a website anyways uh so carbohydrates so it's important that we know what makes up these different molecules so of course or these different macro molecules so we've got carbon hydrogen oxygen which is found in all of them um but this one's specifically going to have that in case you need to help remembering it is carb which makes you think of carbon and a hydrate is a hydroxy like so oxygen and hydrogen so a carbohydrate we know has carbon hydrogens and oxygens and it's going to have a ratio of approximately 1 to two to one think about glucose C6 h126 it's got that 1:2:1 ratio um so this we need to know about the monosaccharides I'm sorry the monomers for it so the monomer for a carbohydrate is a monosaccharide so the polymer would be a of course a polysaccharide so here you can see our glucose this would be um the ring structure that we would find for our carbohydrate and as I said before it's C6 h126 um giving you that uh molecular compound for it or the structure so some different examples would be glucose fructose and galactose um and so you've probably seen these maybe in questions that you've done through the the semester um so what happens is these are the sugars these are the molecules that are going to be providing the energy um when we talking about like um Cellar respiration in unit three so this is one of the important compounds um so if we were to go through a um dehydration reaction and we take out water we can attach two of these monomer together and that makes a disaccharide the die making you think of two so disaccharide would be two monomers together making of course that disaccharide and so some different examples that we have for this would be like sucrose sucrose is glucose and fructose or lactose which is going to to be um oh my gosh glucose and galactose and then we have malose which is going to be I said that wrong sorry sucrose is glucose and fructose lactose is glucose and galactose and maltose is two glucose molecules together I'm so sorry um and so the bond that we have between these is called a glycosidic linkage um and so they may be you know talking the question and they may mention a glycosidic linkage it's just important that we can recognize that they're probably not going to ask you to name that Bond but it's important that we've had exposure to some of these words so that we know what we're reading about in these question prompts um because at this point in the year you know there are some words in those prompts that you've probably never seen before um so it's important that we got to just get a little bit exposure so the bond between them hey ass um is going to be that glycos linkage and so um there's four polysaccharides that we need to make sure we know about um so first one would be cellulose cellose is going to be the uh structural carbohydrate that we have in the cell wall of our plant cells it's what's going to give it a structure rigidity that's why plants are able to you know be upright um kiten we're going to find in our fungi cell wall you know the guy at the party a fun guy no I'm sorry I'm bad with jokes um as well as it makes up the exoskeleton so when you step on like a cockroach that crack that you hear um that's the kiten um in that exoskeleton um and then we also have storage molecules so like our um starch and our glycogen so starch is going to be the structure sorry the storage um polysaccharide that you see in a plant so if you've ever heard someone say oh that potato that's really starchy that's because of the fact that they're just talking about that that's the energy storage that's where all the glucose is stored in that potato um is in the you know potato um and then the glycogen is what we found in our animals um and that's how we store glucose in our liver is our glycogen right um and so it's important that we understand kind of the difference between starch and silos so both of these are going to be found in plants okay we already said it that the starch was going to be the storage material and you can eat a potato you can break the potato down you've got no issues with your potatoes but cellulose that's making up the cell wall you can't break it down and the reason why is because of the bonding that we have it so in our starch we have a 14 Alpha linkage so we can break the alpha linkage but cellulos has a 1 14 beta linkage okay and you don't really need to know about what those ones and fours mean all they're doing is they're numbering the carbons of the structure um not really essential for you to node one4 um but it is important for us just to recognize the difference between the the starch and the cellulos and knowing why we can or cannot break one um and so we can break the alpha linkage but we can't break Bay linkage so you think to yourself say okay well a termite a termite eats wood and it's an animal well it's an as like whatever um anyways so the termite it can't break down that cellulose the terise is not able to break those beta linkages well then how does it do that and so we have to then you know get into Unit 8 talking about ecology and looking at interactions of organisms and we know that there's a symbotic relationship there's mutualistic relationship specifically an obligate neutralis relationship between termites and the microorganisms that live in their gut and so um those ter the microorganisms are able to actually break that linkage for them and so it's important that we can kind of make those extension questions and kind of think about how they could apply um so again that is our carbohydrates it's our sugar it's our grape okay so our next Macro Molecule we need to look at are proteins okay so again they have the carbon hydrogen oxygen as I said we're going to see those carbon hydrogen oxygen in all of our macro molecules always there okay now the important thing to recognize is that proteins have nitrogen which two of the macro molecules will have so proteins is found I'm sorry nitrogen is found in protein and then we also have sulfur and so there was a really important experiment um about it was from um the Hershey and Chase experiment and they basically tracked the sulfur through the experiment because we were trying to figure out what the genetic material was and so because of the fact that we know that sulfur is found in protein if you use radioactive sulfur you could track the proteins in the hersan chase experiment and we'll talk about the other one in just a little bit um somebody just asked a question do we need to know about the specifics of alphaba linkages you just probably might see them in a question I might mention it um You probably don't need to know the exact like hey this one's an alpha this is a beta but it is important to recognize that we can't break the beta linkages um that we are able to break those Alpha linkages it's also important to recognize that plants are able to um store things in different uh structures so like they have the glucose in Alpha linkages in the starch but it's also beta linkage when we're looking at like uh cus okay um okay so the monom for this is amino acid that is important for you to know you should definitely know the of approachin is amino acids okay and so this is what an amino acid looks like okay it's going to have the Amin group that's where we get the amino right we've got this Aman Group which is the nitrogen and the two hydrogens um and so you may be thinking back to your functional groups that you learned you know in your first unit um of your AP bio class and potentially learned in your chemistry class so yes these um functional groups are important they're probably not going to ask you like the name of one um but they could definitely do that if they wanted to um so I re I recommend just at least knowing those S um molecules and kind of having a general idea about those um so uh sorry got distracted um so the second thing that we have attached to it is going to be a car I'm sorry a hydrogen Okay so we've got this hydrogen so we have the central carbon we've got the amine we've got the hydrogen and then we also have a carboxy group that's the other functional group make sure that we knew so the Aman group is going to be basic and the carboxy group is going to be acidic both of which are going to be polar which is going to be important when we start thinking about the folding and the structures of our uh protein molecules okay and then we have this R Group this R Group is variable there are 20 different amino acids that we know about and the difference between those amino acids really comes down to that R Group they all have the Amin group they all have the hydrogen and they all have the carboxy the difference is the R Group there's a different R Group on all 20 of our different amino acids okay so the bond that we have between them is a pepti bond this is specifically between the carboxy of one amino acid and the Aman group of the next amino acid okay so a peptide bond is going to be between uh the carboxy of one and the Aman group of one okay so uh proteins have a directionality to them okay they go n Terminus to C Terminus the N Terminus is talking about the Aman side so if we were looking at a big long string of all these amino acids it's the amino side is the n Terminus and the carboxy side is the C Terminus okay and so we're always going to see that you're going to have the carboxy group right here bonding to the Aman group of the neck and that forms this peptide bond okay and that peptide bond is a type of Cove valent Bond so just like what we learned about in unit one in your your chemistry class or whatnot um a calent bond is just where we're going to be sharing the veence electrons okay so here you can see that peptide bond as I said before between the carboxy group and the Aman group of the next one it forms that peptide bond right there okay and as I said there's our n Terminus so our nitrogen side and then our C Terminus which is our carboxy side and you're just have this long chain of them so in terms of our levels of protein structure we've got four different levels that we go through so the first one we have would be our primary structure primary structure is just like the long string of amino acids so one amino acid attached to the next amino acid um and so the type of bond that we have here is a peptide bond as I said before it's just a calent bond um but is specific to the amino acids and the proteins calling it a peptide bond okay so this is our primary is just making this long string of amino acid sorry about all that extra white I was trying to modify an image uh the secondary structure is our Alpha helix or a beta pleaded sheet okay so um the way that we form this is hydrogen bonds so hydrogen bonds in the backbone so what will happen is that in the structure right here so we have our carboxy right and it's got this um double bond right here the bond o right making that very Electro negative okay so because the fact it's got the double bond o it makes it very electronegative okay and then this hydrogen here okay is going to be you become attracted now within one amino acid they're not attached but if you're thinking about Downstream okay and you're somewhere else on the structure like they'll kind of loop back and so the backbone this is the backbone so you'll see hydrogen bonding on that backbone okay so again I said Alpha Helix which just makes like a spiral and beta pled sheet just makes like it's like a it's just a zigzag and they're just like bonding on the sides okay so here you can see that Alpha helix or that beta pleed sheet the tertiary structure is any bond that you learn learn about in chemistry you've got calent bonds ionic bonds Vander wal forces hydrophobic interaction hydrogen bonds any bond that you know about is taking place here in our tertiary structure okay um and so this is between the r groups so as we said all the amino acids have a different R Group so those R groups are going to of course have different compounds in them different U atoms I'm sorry and so those atoms are going to bond one another whether they're doing a calent bond ionic or calent I'm sorry a hydrogen it doesn't matter but this gives us our final threedimensional structure so now the polypeptide is fully formed but here's the thing not all proteins are made up of only a single polypeptide some of them are made up of multiple polypeptides for example collagen collagen is made up of three polypeptide and hemoglobin is made up of four and so what will happen is these other strands right so we'll have polypeptide a polypeptide B and all these polypeptides will come together and that's what forms our coronary structure okay so it's any bond again but is between the r groups of different polypeptides and that forms this final um threedimensional structure of a protein so if we need more than one polypeptide that's what gets us into that quinary structure so remember if you have questions as we're going you can throw them in the chat there's only 22 in here so there's not really a lot of questions buzzing in so we're good um so now it's important that we recognize the bonding and how the the polypeptide is going to fold okay so we already mentioned the r groups so these R groups can either be hydrophobic hydrophilic or they can be charged okay so hydrophilic just means that it's polar okay so it's going to have the oxygens and the sulfurs and the nitrogens and all those strong electronegative atoms that lead to hydrogen bonds okay hydrophobic means it's probably made up of a lot of nonbond non-polar bonds so you've got the carbons and the hydrogens that are bonded together um and that's what forms the um those non-polar bonds and that kind of is going to fold toward the inside and then charge just means that it has a positive or A negative charge to it okay so as we said before the am group can be basic right so it can take H pluses from the solution and so if the nh2 takes a third hydrogen it becomes NH3 plus it's going to be positively charged okay and so um thinking about that we could have a positive charge on our R group or if the carboxy group lost this hydrogen it would be negative so like I'm just trying to show you positive Nega here um and so that is what leads to it being you know negatively charged so when you look at it you'll see if it's positive or negative why am I telling all this because they could ask you a question they could tell you the r group of one is this and the r group of the other is this how would that defer how it's going to fold and it's important to recognize if something is polar it folds toward the hydrophilic kind of um aquous solution or if it's hydrophobic it will fold toward the interior away from that hydrophilic away from that aquous environment okay so done with proteins moving on nucleic acids and again if you've got questions throw them in the chat um so nucleic acids are important again made up of carbon hydrogen oxygen they're the other one that has nitrogen so remember I said it's important to know what's different right so nitrogen is found in your Amino I'm sorry your proteins and your nucleic acids so those are the only two that we see nitrogen in so it's important that we recognize that okay and then the other one we have is a phosphate group okay so although phosphate is is the other place we find is a phospholipid um phosphate is traditionally going to be found in our nucleic acids so we talked about Hershey and Chase we said that we were using radioactive sulfur and that would code the protein well what they did is they also used radioactive um phosphorus and they were able to code the phosphorus to follow the um DNA through the struct through the experiment to figure out that it was DNA that was the genetic material and that will come up when we get into unit six when we talk about replication and transcription translation um so the mon for this is a nucleotide okay so this is the general structure for a nucleotide it's going to have a phosphate group which is known based on the fact that is a phosphate okay also in case you don't remember back from you know when you talked about macroo not the the functional groups um the phosphate is actually negative charge it's PO for two months um and so that negative charge is what's going to cause nucleic acids to be negatively charged so you may be see questions about you know what charges the DNA DNA is negatively charged Arn it negatively charged it has a phosphate group which is negatively charged which leads to the whole structure being negatively charged okay it also has a nitrogenous base you've heard of these Adine thyine cine guanine and osel those are your five different nitrogenous bases and then you have a pentos sugar pentos makes you think of five so it's going to be a five carbon sugar so this will either be deoxy ribos or ribos depending on whether we're looking at DNA or RNA so the bond between them is a phosphodiester linkage again I don't think you're going to have to be able to name phosphodiester but you should be able to recognize that word in case you saw it in a question and so this is going to be between the phosphate of one nucleotide and the hydroxy group of the other nucleotide now we haven't mentioned all that but let's get there in a second okay so there's a five Prime end and a thre Prime end in terms of our DNA the five Prime end is just again is talking about which carbon is so on the fifth carbon we have our phosphate group and on the third carbon I've got the hydroxy group of the pentos sugar and so that makes this our three prime end DNA is anti-parallel and so we're going to see that it moves from five Prime to three prime here and then five Prime to three prime there it's kind of like when you drive down the road right you're driving this direction and they're driving this direction okay and so if you were to pretend that the five Prime end was the front of the car and the three prime end was the back of your car again you're just driving down the road in opposite directions okay and so it' be like if you hung your arm out of the car that would be these hydrogen bonds that we would see between them okay so just driving opposite direction okay um and so they're anti- parallel they're equid distance apart and then they're just traveling opposite directions okay and so as you see Adine and thyine pair up together with two bonds and then sosine and guanine pair up with three bonds okay and so it's important we know that directionality and then anti- parallel okay so as I already said the five Prime n is where we have our phosphate group and the three prime n is where we're going to have our hydroxy group okay so the nitrogen's bases okay there are two different types of nitrogenous bases we have purines which are going to be made up of a double ring so as you see here this adenine has two nitrogen rings and a guanine that has the two nitrogen Rings okay so I always think of it like your pure uh silver because Silver's uh formula is AG right or it symbol AS AGS sorry um so we're pure silver so pure AG for silver um or the perianes are made of a single ring so the sasine and the thyine and the urac cell that's not pictured um are all part of that where you have that single nitrogen ring um and so I always tell students you want to cut the pyramid um some people say that you want to um like apple trees and the cars go in the garage so it truthfully doesn't actually matter um how you remember it but we do need to remember oh I'm ahead of myself sorry um we need to remember that the purines are adenines and guanines and that the cines are cine uril and thyine um and that example I was giving a moment ago was about the bonding of them um so addine is going to pair with thyine so that's where we say that there's apples in the tree um and then sasine goes with Guan that's why we said the cars are in the garage um and this remember the number of bonds that we have so Adine and thyine have two bonds as you see here and sine and guanine have three the way to remember that is that c is the third letter of the alphabet and so you can remember that there are three bonds as well as it takes two lines to make a t um and so you can remember that there are two Bonds in the thyine okay um so DNA and RNA are slightly different so DNA is going to have adenine thyine cine and guanine and RNA is going to have Adine ell cine and guanine so the A C and G is the same between both of them the difference really comes down to that um the thyine or the urac cell and so if you're given a multip choice question and you're trying to eliminate some of your answer choices if you were asking about an RNA and you see an answer choice that has a whole bunch of thines in it you know that one is not the correct answer answer because the fact that RNA does not have thyine and the same thing as if you were supposed to be answering about RNA and you see sorry if you're asking about DNA and there's a whole bunch of Ells in it you know to just eliminate those answers okay so the sugar that we have would be deoxy ribos versus RNA sugar is a ribos the difference really comes down to the uh Carbon on that second carbon um is where you're going to find that there's um no oxygen or there is an oxygen it's this carbon right here so in this carbon um if it's just a hydrogen attached is deoxy ribos and then if there's a hydroxy group there then that will end up being ribos um and then strandedness we find that DNA is going to be double stranded so it has two strands um and then RNA is single stranded I do have those in quotes because there are such thing as a double stranded RNA and there are such things as a single stranded DNA um but traditionally we do find that DNA is double stranded and RNA is single stranded so that brings us through our lipids and I'm sorry that brings us through nucleic acids so lipids again carbon hydrogen oxygen and then we sometimes will find phosphate in it specifically in your phospholipids now lipids are the Oddball out okay they're just really a a blending ground of multiple things um the thing that really ties all of our lipids together is the fact that they are um all non-polar so every Macro Molecule we talked about before this our proteins our carbohydrates our nucleic acids all those are going to be polar but our lipids are nonpolar because there's so many carbons and hydrogens in them that they end up being non-polar okay so they're also the only one that's not a polymer okay so we talked about Mono U monosaccharides making up our polysaccharide that polymer we talked about amino acids coming together that would make a protein or polypeptide and we talked about the nucleotides that come together to make nucleic acid they all had a monomer but lipids don't have a monomer because they don't have a repeating structure so there's three different um types of lipids that we have to talk about we've got fats phospholipids and steroids so fats are made up of a glycerol okay so you've got this three carbon um alcohol right here um this was a hydroxy when it's a glycerol these are all hydroxy and then we went through of course the um dehydration reaction to attach these three fatty acids to it which then of course created this Esther linkage that we see here okay so this is what we call a saturated fatty acid um because of the fact that it's completely sat at with hydrogen every single carbon is single bonded and it has two um hydrogen attached to it or this last one has three okay again this one's a saturated then this one is going to be un I'm sorry yeah unsaturated because it has a double bond and that double bond causes not all the carbons to be fully saturated fully bonded to hydrogens okay so as I said saturated are going to be all single bonds each carbon is saturated with the hydrogen verus they unsaturated has at least one double bond so not all the carbons are going to be saturated by hydrogen this leads to slightly differences okay our saturated uh fatty acids like so if a fat was made up of a bunch of um saturated fatty acids it's give me more solid at room temperature because those bonds are able to kind of compress together which makes a solid versus unsaturated fatty acids are going to lead to an inability to putot together like a puzzle piece um and so that leads to our oils that we might see okay so phospholipids are kind of odd because they're ampath okay they have both a polar region and a non-polar Reg region um so the polar region would be right here at the tip um looking at the phosphate group okay so instead of these uh Three fatty acids now we just have two fatty acids and then we replaced it with um a fate group so we sve our glycerol we sell this backbone of glycerol and then we have two fatty acids and then at the third position we have a phosphate group attached there and as we've already talked about phosphate is going to be negatively charged and that's what leads to the Head being hydrophilic is because it's negatively charged um versus the Tails will be hydrophobic now what's going to happen is that it's going to self assemble into a bilayer okay so we're going to see that we've got a layer of phospholipids here and a layer of phospholipids there it Associates itself so that the non-polar region is facing the interior of the membrane like so here's our B layer it's facing the interior of that membrane okay um and so that creates this very hydrophobic region this hydrophobic core that makes it hard for materials to pass pass directly through that membrane we'll come back to that in unit two but that's kind of the reason why we are going to see that the the membrane is semi-permeable is because of the fact that that hydrophobic core inhibits things from moving through okay um and then it's going to orient itself so that it's got the um phosphate groups facing outside because the inside of your cell is hydrophilic I'm sorry aquous and the outside of your cell is aquous aquous meaning that it's dissolved in water okay steroids is our last lipid that we have so there are four rings four fused rings um and so these are important for um intracellular recognition and reception and transduction right so they can be seen as Messengers and so like testosterone and estrogen and a lot of these other um steroids they will bind to receptors now as I already mentioned the membrane itself is like it's the interior is hydrophobic it's it's nonpolar and so these steroids are going to pass directly through that membrane and they'll bind to receptors on the inside of the cell and we we look more of that when we get into unit four which is where you see cell communication but we will see steroids in that cell communication so we have finished macromolecules it only took us what 30 minutes to get through those um so now we're going to work on our water properties um and so there are um a couple different properties of water we've got of course polar um which leads to the cohesion and the adhesion we've got the fact that's a universal solvent as well as we've got surface tension um we have this high specific heat and then we also have this less than it's a solid and then we have a little bit we need to talk about with ph um so in terms of polar um the fact that it's polar just means that it has polar calent bonds okay the polar calent bond means that they are sharing their electron just they're sharing it unequally which fat was a healthy one again um you don't want to have um trans fats trans fats are going to be the ones that um like what they can do is they actually like will hydrogenate fats and then that makes them so that they become kind of thicker they build up in your arteries um so it's trans fats you don't want but you also don't want the um hydrogenated fats those are also bad for you okay so polar so we have this polar calent bond the polar Co calent bond is what we're going to see because of the fact that it's sharing the electrons but it's not sharing them equally oxygen is more electronegative than hydrogen and because it's more electronegative it's going to have a PO it's kind of going to pull a little bit deeper Co hold it more to it um which then makes it a little bit more control of it so we have a partial negative at the oxygen and the Hy be partial positive okay um no waxes aren't really that important to know about with lipids um it's not really in the standards um okay so what we see here is that due to this in like the the way they pull that leads to those hydrogen bonds that we saw before okay so here we have that oxygen and here's that hydrogen it's pulling the electron closer leading that oxygen to be partially negative the hydrogen to be partially positive which then leads that hydrogen bond because this oxygen is partially negative and that hydrogen is partially positive and so the hydrogen bond is an attractive Bond so it's not actually bound to them like they're like it's attraction like it's like a attraction due to positive and negative charges okay um and so that hydrogen bond that we see is going to be between our water molecules versus the polar calent bond is in the structure and I know that led to a lot of trouble when I did the review the first day because I asked the students this question and they were all arguing with me and I'm like no no no the question's asking the bond in the water or the bond between the water okay um and these hydrogen bonds are going to come up with our other macro molecules we saw that there were hydrogen bonds in our uh nucleic acids that was going to hold together our um our nucleotides so like for example you saw it right here um these are hydrogen bonds so we have hydrogen bonds in our nucleic acids as well we have the hydrogen bonds in our proteins um as we talked about in the secondary structure so they're going be between that backbone okay um so is important to know that those hydrogen bonds don't just occur in water um they are due to anytime that we do have this um polar coent bond taking place okay um so universal solvent because of the fact that that water has that partial positive that partial negative charge to it um we do see that it can dissolve anything that is also polar anything that is charged so like sodium chloride can dissolve in water because the negative charge of the chlorine is going to get kind of attracted to the positive side of water and then the sodium side will get attracted to the negative side of water so we able to dissolve those and same thing is if it's polar they also have the partial positive and the partial negatives that allow them to be able to form those hydrogen bonds okay and so we already mentioned here the partial negative oxygen binds with other polars the partial positive bins with other polar okay um so thinking about how does this lead to cohesion and adhesion well cohesion is just water molecules being attracted to other water molecules okay um and so um if you've ever drank some some water right the the liquid is attached to the other water molecules okay um or if you've ever seen water beat up on the roof of a car like you put a bunch of little drops of water that wax is of course nonpolar so the that's why you get the little beads but the water is all going to kind of come together or if you've done drops on the top of a penny if you keep dropping on top of a penny it's going to form that little bubble um and that is what is due to cohesion the water molecules are attracted to other water molecules which forms that okay adhesion is water molecules attracted to other polar substances so when you look at a graduated cylinder and you see the meniscus okay you that like how the water's climbing the sides of the tube that's due to adhesion those polar substances in the water they're attracted to each other which leads the water kind of climbing up th those sides um in case you're wondering glass of silicon dioxide so it's polar and so here you can see that cohesion cohesion is water attracted to other water molecules and adhesion was water attracted to other polar substances okay and so together this leads to capillary action um in capillary actions where we see the the water moving up from the roots to the leaves and so there's a little bit of pressure that's happening up in the the um the leaves due to the trans transpiration so the uh water up at the top it evaporates and what that does that pulls the next water molecule and so there's this big long string of water molecules that's being attached to each other that gets pulled up and at the same time the water is kind of climbing the sides of the xylem or the part of the plant that's where the water is um and so we see that cohesion adhesion together lead to that capillary action okay and so here you can see the what I was talking about with the water being attracted to other water molecules as well as it's kind of climbing the walls of the tube okay so surface tension has to do with due to the cohesion we can make a surface on the top of some water okay um and that develops a surface due to those hyen bonds and so what we can do is that it's looking at how much energy is required to break those bonds and for the thing to move through that's why you can skip a rock is if you kind of throw at the right angle it skids across the top and it doesn't have enough Force to break that surface so it just skids across the top okay I and that's again due to those hydrogen bonds so that allows you to skip your rocks or your water Str can walk actually on the surface of the water okay so water is less dense when it's solid okay um what that means is that if we were to think about right now up in the north right their their Lakes have frozen over their ponds have frozen over um and the reason why is because of course it's cold but when you have liquid water those hydrogen bonds are constantly breaking and reforming they're just kind of like moving past one another but in ice we've now got this solid okay and you know that in solid things aren't really moving fast each other and so they're been crystallized so they're holding apart the other water molecules right the hydrogen bonds are inhibiting them from getting too close together and so we've got this space in here and so um when the water freezes it takes up more space and if you remember the formula of density um it's going to be Mass over volume and so since it now takes up more volume that makes water less dense so flow to the top so back to what I was saying about the ponds up north okay is if it didn't do that the entire entire Lake would freeze and all the wildlife that lives in the water would die every winter time which would be a problem and so by us for by the uh water being less dense and forming that layer on the top is going to ensure that the wildlife can survive as well as it keeps the temperature relatively constant it acts like a temperature buffer in there okay and so the ice will float creates a temperature buffer also water has a high specific heat okay that just means that it's going to take a large amount of energy for it to um change temperature um so it's 4.184 jewles if I remember correctly for one gram of water um and so that's a lot of energy and so like you've probably gone and you've noticed that water takes forever to boil it's because it's taking all that energy but why is this important this is important for like coastal regions okay um so thinking about like at night um it's nice and cool on the the um the coast because of the fact that all day long the heat had been taken up by that water and although the water didn't really feel really warm it was taking up all of that energy all that heat okay and then at night here it releases it back out so that helps to regulate the temperature and same thing with our body temperature that's why it's important that we are made up most of water is it helps regulate body temperature okay but we also see that this leads into evaporative cooling when you get really hot like you go and run and you're all sweaty okay your skin is really hot and so the water from your sweat that's all over your skin that heat breaks the hydrogen bonds which causes your liquid water to turn into gous water and so it takes away the heat with you and so that's what evaporative cooling is is is just the using of that heat to evaporate the water which then allows them to cool off because they have less heat okay and last but not least we look at pH okay so pH is going to be negative negative log of the concentration of the hydronium or the hydrogen ions okay um and so I've never seen a question where they're asking us to actually solve anything more in terms of the the pH of something um usually you're just looking at the exponent so like if we have something that's 10^ the -4 um that means it is the pH of 4 and if we're looking at something that's like 1 time 10 to the8 that means it's a pH of 8 I usually just look at the exponent because we're not chemistry we don't need to know like Advanced understanding of that pH what we do have to understand is the like interaction between them okay so as your pH increases your hydrogen ion concentration is going to decrease okay um and then the same thing is as your pH decreases your hydrogen ion concentration is going to increase this is important when we think about like the mitochondria on the in The Matrix of the mitochondri where we have of course the hydrogen as we go through um the electron transport chain they pump the protons from The Matrix out into the intermembrane space and so they could ask you a question about like the pH of the inter membrane space and the pH is getting less I'm sorry more acidic the pH is decreasing because because it's increasing the amount of hydrogen ions that are being moved from the Matrix out into the intermembrane space so those are kind of the questions you might see is more on the understanding that they're inverse than on calculating them although you do have the nice pretty calculators now so I want to check a moment and let's do some multiple choice practice questions so we've gone through all the content in unit one let's just do some quick questions so the scientific examin fold a structure of a purified protein resuspended in water and found amino acids with non-polar R groups were primarily buried in the middle of the protein whereas amino acids with polar R groups were primarily on the surface of the protein which of the following best explains the location of the amino acids in the folded protein um and so I figure you can type in the chat I'll give a moment for you to of course answer I'm going to finish reading through the the question though but you can answer in the chat and then we'll go over it together um so a we have our polar R groups on the surface of the protein can form ionic bonds with the charged ends of water molecules B looking at polar R groups are too bulky to fit in the middle of the prot prot are pushed toward the protein surface C non-polar R groups that cannot form hydrogen bonds with water are pushed into the middle of the protein or D non-polar art groups with different parts of the protein form calent bonds with each other to maintain protein structure so take a moment and see if you can come up with what you think the answer is there's about 21 of y'all in here that are watching right now um so I don't really expect the whole chat to blow up but if you have an answer you can go ahead and you can throw in the chat if you've come up with a question as we've been you know talking you're welcome to throw that in the chat chat um and we've got uh two multip choice questions and then two like mini fqs that we're going to do um but we'll go over it afterward okay so I think I've killed a little bit of time so it says that our polar R groups are on the surface of the protein they can form ionic bonds well we just talked about that ionic bonds have to do with that you've got a positive like a cation and an anion so we know that that's not really what we're looking at here we're looking more if the hydrogen bonds of those polar R groups can then form those charged bonds okay so we know that a is not right because that's looking at the wrong kind of bond B say the polar groups are too bulky to fit in the middle of a protein and that's not fair that's not logical um we're not going to talk about things being too big because it's just going to fold around them if it needs to be an onp poar needs to be on the inside of the membrane I mean inside of the um protein it's going to fold inside and it's going to make itself work out okay cs's nonpolar R groups cannot form hydrogen bonds well if it's non-polar it doesn't have that partial positive or that partial negative to be able to form those hydrogen bonds so C does sound pretty good um so then we look at D just to make sure it says D is non-polar R groups from different parts of protein form Cove valent bonds with each other to maintain the protein structure and that's more talking about hydrophobic interaction and that's an attractive Force so it's really c as our answer so great job Ben Ben um maybe later I can figure out where you are and I can maybe send you a penguin for participating I'm getting it right um okay so the second question we have is rosin Franklin's x-ray defraction image taken in the 1950s most directly support each of the following claims about DNA and so in case you don't remember rosin Franklin's images um it just showed like the X it was photo 51 it formed this little kind of almost like a it's a black X is what if you is the famous picture um and so what are you able to get out of that photo is what's asking you um so take a moment and see if you can come up with the answer I'll read through the answer choices with y'all so you can kind of see if you can come up with the answer um but a the ratios of base pairs are constant B the nucleotide sequence determines genetic information C the two strands of DNA are anti-parallel D the basic molecular structure is a helix so see if you can come up with that answer that you think it is again um this is based on a uh an image so think about what kinds of information you can actually get from a image specifically just an image that shows like the x of the the structure so nobody's voting I'm GNA go ahead and tell you the answer um and so since we're looking at an image thank you NS um so since we're looking at like the a picture of it um we're not able to see what base pairs there are because it literally just showed an X so a is not right being looks at the nucleotide sequence again I'm not seeing as like a super deep image of it to be able to see the actual nucleotides C says that the strands are anti-parallel there's no way to tell that because you would need to know the phosphate group in the hydroxy groups but what you could tell was that it was that X and that X is just looking at um the fact that it's a helix so if you were to like see a spiral staircase and you look down at a spiral staircase you can kind of see the the lines coming in the middle okay and you can kind of see the X shape of it um and so that's what she was able to tell was that it was made up of actually two strands that form that Helix that kind of spiral around each other um originally Waton and cric thought that it was going to be you don't have to attract your answer it's okay um so originally uh wasn't a crick thought that it was making up three different strands made it up and because of this image that's what allowed them to know that it was only two um nucleotide B like polynucleotides that made up that DNA and there's two strands okay so here is our next question so um unit one doesn't really have a lot of fre responses um but this is a component of one of the long frqs um that we can kind of use to kind of help us to do some actual unit one topic of of an FR frq so geneticist investigated the mode of inheritance of a rare disorder that alters glucose metabolism First shows symptoms in adulthood now yes uh that would be a double helix and that's why we know that it is a a double helix um originally Wason cric um felt that it was three strands and that that made it would make a triple helix not double helix which wouldn't have been showing up in that image that image showed her that it was a double helix um so this prompt we really don't even really need to read this prompt okay because all of this is time about some figures and such that has nothing to do with anything we're looking at okay um so when they redid the F frqs they made it so that a is talking about content it's about biology it is do you know your biology okay and so this says the disorder Alters glucose metabolism describe the atoms and types of bonds in a glucose molecule okay so what I need you to do is in the chat see if you can tell me what are the atoms that make up glucose and then can you tell me the type of bonds that you find in a glucose molecule so go in the chat and answer see if you can do that um I'm going to kill some time and tell you about some resources um so other resources you could be using to prepare for you know your AP class as well as your AP exam um is of course the uh absolute recap as I mentioned earlier she's going to be making tons of videos as well she's got tons of resources on her YouTube page um and then she also works with the ultimate um what's that thing called ultimate review packet it's the one that heimler currently was working with but now he's no longer with them um so of course we've got those uh those resources you also could look at crash course or you can look at both in BIO um there's uh my students are obsessed with this guy named um poser his name is Gabe poser um they swear that he's amazing so check out gate poser um there's a another guy named Rob Tate um he's supposedly amazing for my students so we've got some answers in there um so Nas Chan family and Ben Ben are all telling us that we have a CH so we have carbon hydrogen oxygen and they're all saying glycosidic linkage so now we have to think to our and remember okay the glycosidic linkage was the bond between glucose molecules but we're asking for what is the bond thank you nas um what is the bond that we have between a carbon and a hydrogen what is the bond that we have between a carbon and an oxygen what is the bond between a hydrogen and oxygen well those are just coent bonds so you had to say carbon hydrogen oxygen and you could have just used the symbols of CH so that was fine um and that they're held together by calent bonds so you did have to mention the calent bonds because it's asking about in a glucose molecule although you are all right that we do find glycos linkages that is between glucose molecules if we're making a disaccharide or a polysaccharide so great job everybody so our second one we have is during meosis double strand braks occur in chromatids the brakes are either repaired by the exchange of genetic material between homologous noncy chromatids which is process known as crossing over again they're talking about figures that I've not given you um so a is asking us again is the biology question the double strand breaks occur along the DNA backbone so that's telling us that there was a break and that this break happens in that DNA backbone describe the process by which the breaks occur now I didn't specifically mentioned this I did verbally say um some of this information before but I don't think I like went in and actually described it so you may or may not know the answer to this question um but you should be able to answer part of it because you understand how the DNA is held together so take a moment and answer in the chat um NZ supported the fact that gay poser supposedly is amazing so you got that resource if you want to use them um KH Academy has a bunch of uh questions online so you could easily use the KH Academy website they have a bunch of questions that they have Rewritten I think in the last two years so they model the questions better if you're looking for paid stuff albert.io has resource out there but honestly the best questions to practice with um would be to use uh AP classroom so if your teacher is willing to open up the AP classroom um progress performance checks for you um then that would be a great resource I'm actually uh working with my students and I'm giving them a review project in which they're going to do those topic questions each week as we prepare for the exam so if your teacher will open those for you that is a great place for you to get some practice um on multiple choice questions as well as free response questions um if your teacher won't open those for you I think that a lot of people have probably posted those all over Quizlet at this point um but you have that resource if you want to use it okay so the way that we break this bond is we are going to break the bond between the sugar and the phosphate okay so the the sugar of one nucleotide and the phosphate of the next nucleotide so you want to break that Cove valent Bond that's why I said you didn't have to know the actual word break the calent bond between the sugar and the phosphate or break the bond between those nucleotides um or if you did know the word you can talk about hydrolysis hydrolysis is where we're going to break a water molecule which is going to break a bond um and so hydris will break the bond between the sugar and the phosphate or the between the nucleotides so I hope that was helpful um and is there any questions before we um end the live and um you know go amongst our our Saturday and fun um give yall a couple moments to ask questions I'm not really sure if you have any questions or not um but while you're com up with your questions you can throw those in the chat don't forget to follow me on Instagram I've got um Daily Review that I started on February 1 every single day I post uh questions of of look at one Topic in my story and so you can go through those and then I'll answer the question the students have asked the day before um you really don't need to check out the Tik Tok because they just deleted my audio um but I do have a Tik Tok where I post those FR frq Fridays as well as I try to post some resources to help youall it's mostly me just having fun um and then of course you're already here on my YouTube so you know all about my YouTube so it doesn't look like there's any questions in the chat um so