[Music] let's get started um today by firstly revising our sort of big ideas from module 6 so we won't go through obviously the whole module 6 um but we will be revising the big ideas and the key concept so that we can then go on and spend a lot more time going through module 7 so um as you would hopefully by now be familiar with it this is what the HSC syllabus for biology looks like you are studying effectively four topics um the first one is heredity followed by genetic change infectious diseases and non-infectious disease and disorders so um since generally most schools sort of stick in that order of module 5 to 8 um I'm assuming that most of you have done module 5 and six and are now going to start seven or you know like that would probably probably be the majority of us if you haven't if today is you know your first time having a go of both module 6 and seven in case the school has done 5 and 8 just try to follow through the best you can please ask lots of questions and I'll try and break everything down so that we um to those to those of you who have done it you are building on your knowledge and to those who haven't had yet who haven't yet had a chance to do it um you can you know again start to build our foundational knowledge so you can take along with you into term two oh well term three for year 12 so let's get started um so we're starting off by firstly looking at module 6 so the first dot point of module six is asking us to look at mut uh mutagens what are the different types of mut uh mutagens and what mutations do they cause so oh well we look at what mutations they cause in the next slide but that's sort of the first big Point what are mutagens so a mutagen is an or sorry it's going to sneeze um okay it's been happening all day I feel like I need to sneeze but and then I think about it and it just goes away so apologies for that but um as I was saying so a mutagen is an organism that causes mutations um a mutagen can also be known as a mutant so there are three types of mutagens that we're looking at including chemical electromagnetic and natur natur occurring so chemical mutagens include radioactive agents like uranium and other chemicals and it causes structural changes we've got metals that including Arsenic and nickel that can affect the DNA replication process and finally we've got intercalating agents like um ethidium bromide which can cause frame shift mutations and we'll have a look at what frame shift mutations are in just one second um there are also electromagnetic radiations those are like the most prominent ones they happen um they're high energy and they can cause and they are highly penetrative they alter DNA bonding which causes the rearrangement of the structure and um and now we know that you know because of the processes that are occurring in the DNA they can have a huge impact um on on the genome and as a result cause mutations an example of an electromagnetic radiate uh rad radiation um mutant is UV light so radiation from the Sun can be super harmful in high doses and as a result it it can cause pyramidan dimer uh diers so that is when you would have um the bases sort of and actually there's an image here I I was trying to explain it with my hand but I'm pretty sure I've got an image here for us so this is the electromagnetic um spectrum and we can see that in terms of electromagnetic radiation we would know that um you know gamma ray it's goes from Radio to gamma and this side um as you go along it becomes more penetrative so that's that okay moving on um so now here we go these are our pyramidan Diamond so we've got um as you can see so radiate what happens as a result of radiation to the DNA so there can be hydrogen bondage breaking uh breakage so by now as we would know that the um that the bonds are joined so the uh the bases are they have hydrogen bonds you know holding them together so hydrogen bonds here can break they can also be pyramiding di so this is when you can see the bases they turn inwards to connect to one another instead of connecting straight across um there can be a loss and basis base change cross linkage can also happen um there can be single strand break and also protein cross linkage so there are lots of things things that can happen here I would say to really pamine diam is what that is how that happens um and of course hydrogen bond breakage and yeah those are sort of the big ones that we need to know because they have a huge role you know in changing the structure of the DNA okay moving on now to uh inquiry question um two so how does mutation introduce new alal into a population so firstly as you can see here these are um the firstly the results of mutagens so it can have a huge impact on phenotypic on phenotypic expression um and as you can see here we've got ionizing radiation that has affected the DNA so we've got the x-rays or gamma rays over here breaking the single Strand and also breaking the double strand on the other we've got know uh we've got uh nonionizing radiation which causes pyramidan diers to form between um thyine so it can form between thyine uh thyine and um guanine uh no yes yes it's always good to remember that um but this is an example here of diine diers so these are forming between two thine bases so that's that all right let's have a look now at the what happens as a result of these mutations so we've got point mutations so point mutations are known um so point mutations are a type of mutations that happen as a result of damage to DNA and there are two sort of distinct categories for them the first one is H substitution so they can be substitution mutations or they can be frame shift m mutations so with substit so with frame shift mutations there are two specific types there is insertion or deletion so we've basically got the three types of mutations that happen as a result of these and the three effects so the three types are they can be silent mutations So Silent mutations is when there is no effect on the uh codon on the on the DNA so that there's no effect it's silent it doesn't have any effect on the DNA the second is um missense which is uh when we see a change in the amino acid because the codons have been Disturbed there has been a change in the codons finally we've got a nonsense mutation which means that a stop codon has been prematurely introduced which is going to affect the um it is going to prematurely stop the process um and affect the DNA that is being produced sorry that is going to affect the proteins um and the peptide synthesis that's happening so that those are firstly point mutations now we've got chromosomal mutations now chromosomal mutations um is when we actually let me just quickly go back just because I realize I forgot to mention something so with point mutations that's the big category there are point mutations there are two types of point mutations there's substitution when a base has been switched out and then there's framework when either a base has been inserted or it has been deleted and so as a result you get to see three different types of effects I sorry three different types of changes and then the uh and then the specific effects so just wanted to flag that out okay let's have a look now at um chromosomal mutations so chromosomal mutations um usually occur as a result um of errors that happen during meiosis and crossing over and that could be because crossing over occurs in currently so there can be chunks of DNA that was screwed up and that can cause structural mutations to happen um we can also see cister chromatids being incorrectly separated so during anaphase um you know when the uh chromosomes are supposed to separate the DNA could not like it may not be separated properly which can then again cause a number of mutations as well soor let me just check my Chargers plugged in just sparkling okay all good all righty just making sure yep okay perfect so let's now have a look at um the effects of it the effects are usually severe because now we've got issues um you know within the DNA happening um at a bigger level like it's happened during myosis and it is going to affect the phenotypic expression but it's also going to affect um their gammies in in some cases it can affect their gammies as well depending on what the mutation is so there are four types of structural CH chromosomal mutations they include deletion so deletion is when a chunk of that chromosome has been deleted as suggested by the name there is inversion where when a part of that DNA has been inverted inside out we also have translocation when a part of the DNA has been misplaced so sorry uh the chromosome has been um displaced and finally we have duplication where a part of the chromosome has been duplicated so those are the four types of structural mutations and um if you've got mutations in the number of chromosomes which can again happen if you know we've seen if it's happening during meiosis and it affects the separation of the strands there can be mutations um in the number of chromosomes and there are two main times there's anipo and polyol so anipo is when the overall number of chromosomes of The Offspring differs to that of the parents uh of the parents so for example in Down syndrome the individual has 47 chromosomes instead of the usual 46 chromosomes and that is because they have um three copies of chromosome of chromosome number 21 so that's at a then we've got poly which is when an organism contains more than two sets of homologous chromosomes so for example um tripol is a condition in which the fetus has three copies of every homologous chromosome instead of two copies um and that is is obviously going to have a severe effect um you know on a large number of genes so um we've got uh so as I've introduced you early to toots bath here are some examples of uh for example um uh little guides to looking at mutations and these um and I he I tter biology here at cheat spots at T biology pdhp and English advance and this is um you know one of the examples of how we like to deliver our content obviously um we have a very similar sort of slide uh not slide structure sorry you have a very similar structure in terms of you know go through the slides but um some of the resources and the way in which we present a Content includes like infographics like this which can be so helpful in visualizing what is happening um and these are here for you if you want to have a look and use them and add on to your notes as well okay now let's have a look at the second Big Dot point which is biotechnology so with biotechnology uh inquir question is how do genetic Technologies affect earth's biodiversity so this is something that you will come back to um that you have obviously looked at briefly in module 5 and you will come back to in module 7 and 8 as well like you will come back to the UDA of biotechnology um and we are going to go through module 7 in a l so you'll sort of see how that TI up with module 6 so there are three different types of um users of biotechnology that we are looking at firstly we're looking at the use of biotechnology in health so medical biotechnology and examples of that include of course bof Farms but those are not just the only one um and the big examples you know of Biotech of of medical biotech is vaccines and antibiotics having now you know gone through the pandemic we are all very aware of um vaccines and you know antivirals and stuff and how they've played a huge role um in curving the pandemic there are also stem cell treatments that are being developed and that have uh some of some have being developed some are being developed and there are changes being made um and that and that includes skin grafts treatment of of cancers and autoimmune diseases we also have industrial biotech so some of examples include um biocompatible materials like biopolymers derived and also produced by bacteria or plants um and and as well as biodegradable Plastics uh living in a world where we are currently dealing with the effects of climate change um along with obviously many other issues biodegradable Plastics play uh you know will have uh will play um a huge role in the way in which our world functions so that is again something that is being constantly researched and improved we also have the use of enzyme biotechnologies and um processes like fermentation and food production that once again for a huge role in making industrial processes more efficient finally we've got environmental biotechnology um and we will again be talking about all of them in a lot more depth but I think environmental biotech is one of those um that we sort of no like we we we use every day but we don't really think about that as like biotechnology right so we've got um bi uh bio remediation which is development of microorganisms to help clean up pollution and we also have the use of genetically modified crops and organisms um and agriculture that is being used to better um you know suit a changing environment and that is something think for example you know BT cotton corn um a bananas Cavendish bananas all genetically modified so it is something that we obviously uh you know that we interact with every day use every day but we may not actually consider it biotech so uh here is um so here are the different the three different types of genetic technologies that we will be looking at um in this module you will see that in the syllabus some of them are specified so the ones that I've highlighted in um pink there for you those are the ones that are specified in syllabus but of course you still want to know examples of the other of the others as well so we've got reproductive Technologies including artificial insemination which is used in the livestock industry we've got invitro fertilization so IVF which is um you uh which is a fertility treatment and finally we've got artificial pollin uh pollination um which is used in agriculture so these three are reproductive Technologies then we've got cloning techniques and cloning techniques include firstly whole organism cloning so it's used wiely in livestock industry I think by now we would all know Dolly the sheep so Dolly the sheep is an example of um of whole organism cloning there are many other out there now um another one is in jazz the camel um that was a camel in the Middle East that was um cloned we also have therapeutic cloning which is uh happening in medicine again a field that is being still being researched and explored finally we've got gene cloning which is happening in both medicine and Industry so like I said the ones in pink are the ones that are highlighted in the syllabus so you definitely need to know those and the ones in blue of course are extra examples that are still think you should know just in case you know you get a question where you don't want to keep talking about one thing and you can bring in other relevant examples uh and and the syllabus also says including but notlimited to so it might it's a good idea to have some extra examples up your sleeves uh and finally we've got recombinant DNA technology so that includes Gene sequencing which is used in medicine and research includes trans Genesis um which is also used in agriculture and biotech gene therapy Alysa and crisper which is used in medicine and is a molecular tool so here I've got an example for us so we've gone through the content and now um let's have a go at adapting it to this uh to this specific question which is from the 2019 payer the application of reproductive Technologies in plant uh in plant and animal breeding limits genetic diversity so to what statement is this uh statement correct a question like this to what exent you need to specify what your point uh what your opinion is you know you have to say to a significant extent this is true or this is um this is uh this is not true or or this is um untrue to a great extent something like that where you actually answering the question um and with a question like this you need to be able to like there's a lot that you can talk about so structure is crucial it is six it is worth six marks so that's very important um so structure is crucial and organizing your points to sort of come back to this big idea almost think a bit like an English essay you know you want all your evidence to link back to your main thesis your main contention your main argument so kind of going um through that structure so let's not be scared let's not have a go at um how we would structure this so if we've got a question like this I would obviously want to have an introduction that gives me definition of um you know reproductive Technologies and how they are being used in plant and animal breeding and evaluation right so so that is the part of how they're being used evaluator for me and through that answer to what extent do you think this is true then in your body paragraphs you are um giving me examples and arguments to link back to your main contention and proof that hey you are right um and here I might talk about two specific Technologies so for each one I will Define what they are describe the um so describe Bri give a brief um outline of how they work an example and then comment on dozel liit genetic diversity so I have to give examples of um reproductive technology because that is what the question is asking me to do the question wants to know if the application of reproductive Technologies in plant and animal breeding limits genetic diversity so I need to give examples to back my point up here and finally uh we want a conclusion that ties everything together and reinforces your uh your evaluation so here you'll link back to body paragraphs again like in English you sign posting your themes that is kind of what you're doing here so that is that let us now move on to module 7 um