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00:22 Okay. Okay folks uh let's useful reminders, just remember the quiz

00:34 . Due date for blackboard quizzes. until it's been extended, it says

00:41 , yeah, 13th but ignore that will be due on It will be

00:47 on the 20th. Okay so Um that in mind. So you got

00:55 10 days to complete that, it be open tomorrow. So um Uh

01:04 make note of that, but the dates for smart work, they're still

01:07 same 13th and 2013. This Sunday next week from Sunday. Um Okay

01:18 today. Yeah we are and this this is not correct, we're on

01:24 1. we'll finish, we're gonna when we come back we'll get all

01:30 way through At the end of 14 we come back on Monday um In

01:38 weeks or a week and a half finish up 14 and we'll have the

01:42 trophy most of the photo trophy stuff to do, which is not

01:46 so um so we'll finish it up . Uh remember the cost of schedule

01:51 opens tomorrow and kind of I guess at midnight tonight. So um so

01:59 aware of that. Um And so remember that the exam is gonna be

02:06 end of the week when you come , so we come back on the

02:10 on the 21st we come back and that examines the end of the

02:17 Okay so um alright so I just to do a little bit of a

02:26 of some of the stuff we talked last time So uh so with reduction

02:32 . Right. So kind of uh this in the context. So,

02:39 the bench we've been talking about um . Right? So reparation and we

02:49 at our at this diagram. We at a lot. I simplify

02:54 Like so electron transport chain um uh donor feeding it. Okay. Except

03:05 at the end. And so we then that um this system of maintaining

03:16 flow. Right? So it's really critical. Mm hmm. Keep the

03:22 going right. And as we energy is used if you transfer,

03:31 are energy is used to pump Right? Which we then? So

03:36 the end last time. Right. thank you. A couple of the

03:44 release of protons going down the gradient the charge attraction like that proton motive

03:51 . Right? Delta P. That produce a tps. Right. Um

04:00 so the redox thing is all We can look at molecules or reactions

04:07 evaluate, you know, the reactions except ear's and the molecule form the

04:17 as a potential dome. Right? whether it's in the C. 02

04:23 an acceptable glucose is the end And that as a donor.

04:27 That in terms of except er molecules be good at it and they can

04:31 bad at it. They can be in the middle. Okay. And

04:35 um uh so how do we arrange things? Right. So that's how

04:40 can maintain flow is because we have uh donors. So if you're a

04:46 except er you're probably a good Right. So we look at the

04:52 couple. Right? So these things in pairs, Right? And H

04:56 H plus pair A 02 water Okay. And so in each half

05:03 that pair of ones to accept reform is the donor form. Okay,

05:08 whether it's H plus is the accept . Okay, H to the donor

05:18 . Okay. And so valuing we can see that H plus as

05:23 accepted is pretty bad. Right? the reduction potential positive delta G.

05:30 , so um uh so there you . Okay, maybe it's a bad

05:34 for maybe maybe the glucose is a donor form. Right? And it

05:39 H two? Sorry, H two be a good donor and it is

05:42 remember reverse the signs. Right? now it's plus 4 20 and uh

05:49 becomes a negative delta G. so H two, they don't write

05:53 bad, accepted. Okay, conversely at the oxygen water, couple oxygen

05:59 . Except er a lot of energy in the process. Water. It's

06:05 gonna be a bad dough. Because it's gonna take a lot of

06:08 to get electrons from that. Although that does happen. Right,

06:14 sun energy from the sun is what to be able to pull electrons from

06:19 . Right? Because it takes a of energy to do that.

06:21 But auction is a great accepted and in that couple the accepted is

06:26 The donor is bad. So and how it is. When you look

06:29 these different pairs, it spans the , right? We can see the

06:33 right in front of us, write the top in terms of except er

06:38 at the bottom in terms of But then it flips in terms of

06:40 donor form. Okay, so we these so we can maintain then flow

06:48 five putting strong donors to successively stronger stronger except ear's. And so that's

06:55 this is about. Okay, so go from a negative reduction potential.

07:02 . To a more positive one. . And so that reflects the fact

07:07 strong donor, stronger and stronger accepted we go go from left to

07:12 Right. That's what maintains electron Okay. And if you do that

07:18 you got any then of course. as we're doing this we're generating a

07:25 delta G in the process. Energy release. Use that to pump

07:30 out. Okay. And then capture energy as shown here with a proton

07:36 force producing a T. P. . Okay, so um and speaking

07:43 that we might over that as well time and we can see that

07:52 And so um so remember then the maintaining this? All right? What's

08:04 of course allows us to maintain this of course the the setup of electron

08:12 except ear's right. That right that electrons provides the energy to use to

08:18 a proton break. Once we get then we can generate this proton motor

08:24 , right? Which is based on written hydrogen ions high on one side

08:29 than the other. Because of course ions are what ph are all

08:34 So the ph difference equates to a ion difference. And so we have

08:38 concentration difference high low and then the difference plus and minus inside.

08:49 And so both those things draw the in. Okay. We can't they

08:54 swim through a hydrophobic by layer. repelled by it. So you get

08:59 you give them a conduit, then become in released energy and that's what

09:03 A. T. P. Is all about. That we ended

09:06 with last time or we finished last . And so this is what allows

09:10 to you to couple the energy released the proton gradient as they come through

09:17 the energy requirement needed to make a . So that's where that comes

09:21 And um then then we of course that for each. Um So so

09:28 course what's fueling this is the the oxidation of some food source that leads

09:35 the production of electron carriers like this electron carriers like this and this and

09:44 are the things that interact with the transport chain giving up electrons. And

09:48 of course creating the whole proton gradient . Okay. And so for each

09:55 uh any th oxidized eight protons are out. Three come back in to

10:01 an A. T. P. ? So that's how we get these

10:05 . And so we can look here the tally of everything. Okay?

10:12 and so just to make one last . Let me erase. Okay,

10:18 not going to erase and try Okay. All right. One time

10:30 options erase, not working. Alright. So just to make one

10:35 point here. So how this how is tied together. Okay, so

10:41 we talked about redox and arranging arranging donors just trying to accept others.

10:47 and then then that energy is used pump protons. Remember all that is

10:52 by the donor upfront. Right? food source if you want to call

10:56 that. Okay, that is broken . Oxidized capture electrons that at certain

11:02 forming in a D H F E H to write those are what feed

11:07 system. Okay. The terminal except the end we breathe right? We

11:11 in air 02 was what serves as terminal except er can be lots of

11:15 things for other types. Okay, everything all this is connected that

11:20 Okay. And so tallying up Remember the two ways to make uh

11:26 ways we make a tps in this , substrate level false correlation which doesn't

11:32 a whole lot but it's some both and in the Krebs cycle and then

11:38 other energy carried molecules and a th it needs to at uh form that

11:46 th form that uh the three stages it needs to in the Krebs cycle

11:51 then the total of them There. so we can then multiply of course

11:56 values. Alright, times 10 times . Okay you give us These values

12:03 . So a total of 30 but is the theoretical value on paper but

12:13 does that occur because bacteria archaea used use the proton gradient for functions other

12:24 um made the 80 ps. Right that gradients coupled to to maybe bring

12:29 molecules in or out of the cell to moving a flagellum of this motel

12:36 other functions. So it's not all making a DPS necessarily because remember remember

12:41 concept energy releasing process, Republican, requiring process. And sometimes that maybe

12:48 making a tps but sometimes it's not it's from bringing molecules in going up

12:56 the gradient or out against their gradient whatever. Right So there's other other

13:01 for it besides making http. So realistic range is probably somewhere between

13:10 30 but maybe upper upper teens to to low twenties somewhere there obviously it

13:18 depending on the gross state of the and what the needs are. Okay

13:23 um Okay. Is uh any Okay so let's look at here comes

13:33 first twitter question. Okay and so a look at this. Okay so

13:41 choices A. B. And And so just to clarify what I'm

13:45 for, there's a boxing. So . Okay B. Or C.

13:53 see, see and then B. over here. Right, okay.

14:02 abc which one of those represents an respiration. Okay, anaerobic respiration agent

14:17 H. Two is so far so . It's actually see and that's

14:34 Okay, thank you. And so don't we don't go over the sulfur

14:49 but this is uh we look at of these reactions and the context of

14:56 processes but um what part of that sulfur? Uh we get our so

15:06 our in our phosphorus ah a lot times through just eating the protein in

15:14 diet, protein in our diet gives nitrogen gives us sulfur, sulfur is

15:18 to make two amino acids consisting of . So it's critical for us.

15:24 But we particularly get it from organic . Um uh then of course the

15:30 breaks down this material organic material and sulfur in the process as well.

15:36 so it looks like everybody's answered. I'm gonna go ahead and flip

15:41 Let's see what we got. Okay let's see at 53 A. And

15:48 . Equal. Alright let's see. who answered A. Anyway, Well

15:56 know that 30 of you did. which one of the 30 answered

16:03 Also look at names. Let's see answered it. Alright I'll get my

16:10 . Alright let's see. Uh Hey . Mm hmm. Okay. That's

16:19 it doesn't tell me. I don't what the color coding here is.

16:22 I guess I don't know. So answers? Come on. Somebody

16:24 A who answered A Who answered What did you answer? Seat?

16:32 did you answer? What did you ? Who answered? A. For

16:37 sakes. Hold up your hands. you. I'm gonna give you 100

16:41 today. Okay. Professing up. don't answer. What? So what

16:45 you so afraid of? What are so scared of dignity? Have I

16:52 embarrassed anybody in your like this? course not tell you what you're gonna

16:56 . Goodness gracious. Okay. So why do you think it it

17:04 ? So it's more it's more what would you say terms of oxides swimmers

17:09 reduced for? Yeah correct. It's more oxidized form of of the sulfur

17:17 . Okay so A. Is the answer. Okay and you were afraid

17:25 didn't want to fess up. Alright A. Is correct that you as

17:29 said uh that sulfate represents the most form of those three contacts.

17:36 elemental sulfur sulfate and H. two . Okay. Now you could I

17:41 expect you to do this? Um not gonna have to do it,

17:44 not required to do it. you won't even be tested on

17:47 Okay. But if you wanted to back to chemistry class and figure out

17:52 states, right, You find that is a plus six. That's a

17:59 sulfide. Right, that's zero. course. Okay, let me let

18:04 get this stuff out of the way Back then up there. Okay,

18:12 um of course I'm not expecting to that. But but the thing about

18:17 oxidation state of molecule is one way look at is how how electron poor

18:23 it in a way? Okay. and so sulfate can be reduced to

18:28 to to sulfide. Okay, sulfide is the more reduced form.

18:35 It's sulfates become reduced to form And sulfide is a form that can

18:42 as a donor. Okay, so little trophy. Right, That uses

18:47 compounds for energy. Could use iron sulfide oxidized and get the electrons from

18:53 . And then that will be part its what would feed its electron transport

18:58 . So this would be um Okay, B and C. Or

19:08 . And A. Is reduction. , and so electrons oops goodness.

19:20 right, let me uh I don't what I just did there. There

19:25 go. Oh shut up. All , back to here. Okay so

19:31 on let me try again. Oh damn it. Okay, try this

19:45 . Mhm. Oh thank goodness. um Okay so as mentioned these are

19:58 zones just abbreviate oxidation, oxidation Okay so um so this is basically

20:12 segue to get into anaerobic respiration. so um anaerobic respiration. Obviously you're

20:18 something other than oxygen as a terrible er um and so sulfate serves that

20:24 in this example um in sulfur reducing for example we'll talk about those

20:31 Um And so when we look at , remember it's which what's at the

20:39 the terminal accepted? Okay and so look at um e coli,

20:45 this is what can do in terms anaerobic restoration. Thanks to get to

20:50 on over here. Right, Terminal reductase. That's the enzyme that air

20:56 with that terminal acceptance. So it's , it's oxygen. Okay. As

21:04 can see here, if it's it can be one of these.

21:11 and so among anaerobic aspiring bacteria, can vary from what they can use

21:17 and they can use multiple terminal except as eco act him. And if

21:23 if you're able to do that then have to have the particular type of

21:30 what's called terminal oxidant reductase because that's to be specific to the particular

21:35 Alright. And so the pain was to it. You can use uh

21:40 of these internal consecutive. Now of you can also uh have different donors

21:47 feed the system. Okay and um remember the N. E.

21:53 H. Right? That's a product the oxidation of glucose for example.

21:59 . So as far as the glucose break it down, you make any

22:01 but some of these molecules can act direct connect directly with electron transport chain

22:08 eight hydrogen and lactate. And so these are all donors that give up

22:14 electrons the system and then terminal terminate one of these terminal except ear's.

22:22 . So um it certainly gives bacteria can do this versatility. Right?

22:29 um in addition to this, the . Coli can also ferment. So

22:33 a three headed monster if you will trapped. Um Now so again,

22:41 memorize tables. This isn't even in notes. I just want to put

22:44 in there just to show you uh things. One is these are tables

22:50 for nitrogen and sulfur, nitrogen sulfur tend to be ones that are involved

22:57 a lot of times in either an respiration or in Little trophy.

23:03 so the little trophy is uh use oxidation of a inorganic molecule to get

23:11 from it, get the electron and electron transport system. Um And so

23:17 so so you're gonna see these nitrogen sulfur compounds in different contexts in one

23:24 . It's okay. Using it as terminal acceptance. Okay. The other

23:29 is oh I'm a little trophy. these are the forms I can

23:33 Okay. And so when we look both tables, look at focusing on

23:37 oxidation state. Okay, so looking this. Right, so here's a

23:44 value. Right? These are more forms. Let me just move

23:51 So more reduced forms. More oxidized . Okay, more reduced. All

23:58 up here. More oxidized. Of . Right. And so the forms

24:04 will be used for the terminal except will be the more oxidized form because

24:11 have room to hold electrons. But way. Alright, so it always

24:14 back to to this diagram again. , so you're more oxidized forms here

24:30 more reduced here, defeated. So more reduced forms, get the electrons

24:39 the system, then hand them down the more oxidized forms which then become

24:43 . Okay, so nitrate is very uh terminal except er in internal

24:50 A lot e coli and a lot its relatives can can do this.

24:55 salmonella entra factor etcetera. Uh If a lab, a lot of the

25:01 you're using there are types that can this um inspire and aerobically using

25:06 Uh So nitrate and nitrite are both common. Okay. Um Now,

25:13 terms of the other end, looking eat a inorganic source ammonium, mine

25:19 a good choice. Okay, she oxidize ammonia to nitrite. Nitrite to

25:25 . So those are kind of the that little troll fuses. Okay,

25:30 then it was sulfur similarly more oxidized up here. Right? And so

25:38 serve as terminal except ear's. So sulfate reduction sulfur reduction sulfate. Very

25:47 among those types that acts as a sector. Okay. Sulfide on the

25:52 hand, this is the more This is what a little trough would

25:56 . Right? Or elemental sulfur in cases. Okay. Because if the

26:05 the purpose Okay. Mhm. Is um So for local trophy won an

26:13 source before a source of electrons. ? So take it the molecule

26:18 Get those electrons right. Sophie would be a very good would not serve

26:23 good purpose for that. Okay. sulfide would it's the more reduced.

26:28 . So that's again looking at what we talking about? We're talking about

26:32 at the trouble except er end or appear feeding it. Right. And

26:37 choices are gonna be based on what use for more oxidized form that's really

26:41 fit. Okay. Um So remember it's uh uh you know what's available

26:48 an organism both move ever and so going to have to make these decisions

26:55 on this kind of chemical properties. . So um Okay so as I

27:02 , nitrogen sulfur as electronic sector is common. So in in terrestrial ecosystems

27:08 certainly nitrogen compounds. And so here we're looking at nitrogen forms of nitrogen

27:15 accepted. Okay, terminal acceptance for . And so nitrate. So in

27:21 direction we're going more and more And so um the and so bacteria

27:33 have not necessarily have all of these use as a terrorist criminal inspector.

27:39 have pairs maybe nitrate nitrite. Uh happened? But they may have two

27:44 three of these. Not not all them. Okay, now this term

27:48 is similar tutorial. Okay, there's similar story processes and dissimilar Torrey.

27:55 . What that refers to is in process is the is the end product

28:02 the process, one that the cell onto and becomes part of the

28:07 Okay. The end product is used is incorporated into the biomass. That's

28:13 similar story. If it's this similar , it's not especially let go into

28:17 environment and they can potentially be used others. Letter nearby. Okay.

28:23 as similar story and discriminatory. Um so we look at nitrogen, we'll

28:28 more closer at this in the next . The nitrogen cycle. And so

28:33 election cycle uh takes three different forms nitrogen. Okay. And there's three

28:41 processes associated with actually more than But we're just looking at three right

28:46 um that relate to how it cycles the environment. Okay, so nitrogen

28:52 , or often called the triangle is to life on earth because remember that

28:58 ecosystems, um your primary producers Your plants or your allergy uh photosynthetic

29:06 right there. The foundation, Um because they support all the levels

29:10 them. Okay. Different loads of . Um whether herbivores, carnivores et

29:17 . Okay so you got to keep happy and what keeps them happy of

29:22 is light right? Photosynthesize light Others there's some variations there we'll see

29:29 water for sure. And but they make their own minerals. So nitrogen

29:35 . N. P. Alright are the environment are scarce. Okay Because

29:42 soon as they appear they're rapidly Okay so um when you do see

29:49 of natural phosphate in the environment that set into motion certain processes sometimes we

29:55 can be problematic. Okay we'll often about that in unit three.

30:00 Um But one of those is actually overuse of fertilizers can lead to bad

30:06 . Will mention that briefly here in second. But nonetheless um uh the

30:11 cycling of these different nitrogen forms important all life is this is all driven

30:16 bacteria that do these different sides of triangle. Okay. And so we

30:21 atmospheric nitrogen Which of course is almost in the in our in our

30:28 And so in order to bring that us an ecosystem we use fixation.

30:32 so that's a process uh bacterial process does that. So now we bring

30:37 into the environment out of the atmosphere the environment in the form of

30:42 Um Most of the process here is to plant bacteria associations. Um I'll

30:54 that for you at three. But that's the primary form that brings actually

31:00 um A two and then we have course, little Trophy is down

31:05 Alright, so using nitrogen ammonium as energy source. Right? Oxidize it

31:11 form nitrate nitrite to nitrate and other that's done. So that's this is

31:16 Little Trophy. And then the advocation anaerobic respiration. Right? So

31:22 what part of the process are we at? What's feeding the electron transport

31:26 or what's at the end? So in the identification, we're basically

31:30 at this. Mhm. Right that's what that part of the triangle

31:37 . Discriminatory de notification. So, into is forming back into the

31:44 Okay. But of course that can balanced by the loss of hydrogen can

31:49 balanced by fixation of it. so the there is a process that

31:58 will can form ammonia as well through I think it's uh yeah, nitrate

32:08 reduction. Okay, you can actually , don't worry about writing this

32:13 you know, to, you three to ammonia. That's another way

32:17 can go. That's actually what's called modification reaction. So that that can

32:22 ammonia as well. Can I? that's and that's gonna be assimilated.

32:27 . That's what we call it. similar story process. So the ammonia

32:29 has taken in and used by Okay So nitrogen compounds then you can have

32:39 compounds. So so we're gonna in a few minutes. We're gonna see

32:45 same components, both nitrogen and but they're going to be in the

32:49 of the oxidized forms that become Okay, as we look at little

32:54 . Okay, so here we're still anaerobic respiration. So with sulfur compounds

32:59 sulfur, these kind of metabolisms with are very common in marine ecosystems.

33:08 has a much higher sulfur content than freshwater or even terrestrial environments.

33:14 so because of that higher level of in seawater, you see these kinds

33:20 metabolisms more commonly. Okay. And in terms of respiration and thermal except

33:27 again, no one bacterium will have of these as eternal. Except we

33:32 have to be three. But the is we are re reducing again,

33:37 , reduced the sulfate and so on we get to sulfide. Okay,

33:42 more the most reduced form here. , so uh so one of the

33:48 you see in marine environments, particularly depths of the oceans are these thermal

33:52 . Okay, so think of them underwater volcanoes that are spewing out lava

33:58 gasses and stuff. Right? So among the products spewed out their heavy

34:04 iron so hard and so far, and gas um C. 02.

34:13 so uh the iron and sulfur together of give the appearance of a very

34:20 smoky the area around the fence. like something just smoke everywhere. That's

34:28 it looks. But these conservative nutrients course for things like little tropes down

34:34 and they do okay so we have metabolisms going on products of one being

34:41 by others as reactant. And so one of the things you do see

34:45 because of course we're spewing out lava is hot. Okay, you're gonna

34:50 a temperature gradient around this vent which be very hot at the mouth.

34:56 you see it you'll see hypothermia files and farther down thermal files than your

35:01 music files are like us. They're moderate temperatures. So you'll see a

35:05 range of these kinds of types here different types of sulfur sulfur metabolism.

35:12 . And so some of the things see are Using like H. two

35:16 . As a as a source or . two or iron. Okay again

35:23 are all materials that come out of that was out of the bank.

35:28 so the activity of sulfur oxidation here be then used. These can then

35:34 used for example by a sulfate Okay that will use this for anaerobic

35:43 . Okay, similarly other types can these other things as um every three

35:48 can be used as a trouble accepting well. So so again, you're

35:52 to see all these kinds of metabolisms here. Um And then remembering little

35:58 are also autotrophs. They pick SEO . Right? So they'll have

36:03 0. 2 as a vent gas can rely on for that property.

36:08 And then what you also see obviously of microbial life going on but it

36:13 is rich in in uh higher more life as well particularly these things.

36:20 So before I get to that so Central is a term that relates to

36:26 kind of where everybody's kind of feeding right where yeah materials being oxidized,

36:33 down other other types then use those for their own metabolism and everybody's kind

36:38 working together so to speak. That's we call central protect. So again

36:43 I mentioned in in addition to that microbial life down here it can be

36:47 thick. Uh You'll also see symbiotic between these types and these what are

36:54 giant tube worms. Okay and so they'll be like a um they'll stretch

37:01 like almost there back this way. be around these vents and take up

37:06 space like maybe a football field in . Okay. Just full like a

37:13 of wheat in the field of these worms. Okay. And um they

37:19 a inside is a symbiotic relationship with types of bacteria that used the oxides

37:25 reduced the sulfur compounds for respiration fix . Two. And the scientific station

37:31 organic materials and that's what these worms off of. Okay so but again

37:37 they're quite plentiful in numbers around these . Uh do these associations with these

37:43 . Okay um now uh so the part of of anaerobic respiration has to

37:53 with what we see commonly in wetland . Okay. And you'll see a

38:04 of respiration. Anaerobic respiration types based terminal except er that relates to

38:13 Okay. So we're going from top bottom here. Okay. And so

38:18 see a difference in reduction potential from positive up here. Okay. two

38:27 negative down here. All right. so and when you do kind of

38:34 environmental field studies you measure all kinds things like nitrogen phosphorus levels. Just

38:40 . Um The levels of ph is one. But also you can measure

38:48 potential. Okay. There's a probe can use and you're basically looking to

38:52 how positive or negative is the Okay. So if you're out there

38:57 you're measuring these redox potentials if it's super super anaerobic environment, what would

39:03 expect to see on your meter should positive or negative. Yes. on

39:09 of 50% chance of being right, . Absolutely negative. Right. Remember

39:15 has that positive reduction potential. And so an area that's positive equates

39:22 an area that's likely aerobic. But as we go to the negative

39:26 , we're getting more and more Okay. And so uh so we

39:31 at the hierarchy of these types of . Okay and again we're looking at

39:39 accepting. These are all different types terminal except ear's whether it's oxygen or

39:44 or uh manganese dioxide or iron. . Or sulfate or C.

39:53 They're all serving as terminal except Okay. Different forms of respiration.

40:00 um so as we go further further we're going to processes that are more

40:04 more anaerobic. Okay and so one the couple of things here is the

40:09 right? These metals like manganese Okay as they become reduced um they

40:17 times very common with metals, metals be very insoluble, okay in in

40:24 . And so as they become reduced tends to make them more soluble.

40:29 so it's an important activity from the that it makes these metals more soluble

40:35 more accessible more a similar can be . Okay and so not to confuse

40:41 here if we're calling this process um need to be called the similar story

40:46 reduction. Okay so that means the is using that except for reducing it

40:51 then the metal is let go. doesn't hold on to it. Okay

40:54 that does make it available for So and and it can be a

40:57 sustainable form that way that can be by others in the ecosystem. Um

41:02 Torrey reduction. It would mean that does hold on to it so it

41:06 go both ways so I can hold to it and let it go and

41:09 different between this similar story. A story. Hold on to it or

41:14 . Okay. And so um so most anaerobic here alright is method of

41:22 which is right here C. 02 form methane. Okay. Very easily

41:30 by um by the presence of Okay so typically gonna be the process

41:36 uh uh at the lower depths really . Um And the reason being is

41:42 ceo too if you recall the table the relax table, C. 02

41:48 at the very top right? The electro negative negative reduction potential auction at

41:54 at the bottom most positive. So c. 0. 2 has

41:58 been accepted. Okay so you have make sure it's very interesting. And

42:05 uh you you can remember that with um and then with delta view if

42:11 can have a high level of reactant it can make it go. Make

42:16 process go. It actually uses Two. And we'll see this in

42:21 next slide actually you can use hydrogen a source of energy. Okay to

42:27 this process because Sio two is gonna really bad. That's acceptable. But

42:30 you have a choice to which is good you can kind of offset

42:33 But also if you have a lot hydrogen gas. And so you get

42:38 lot of methods of justice where there's lot of fermentation by other organisms because

42:42 give off a church too. So we have the same trophy thing

42:48 products from one records for the So you see methane engines always around

42:53 of other bacteria like fermenting and things giving off H. two. Oftentimes

42:58 a byproduct. And so that helps to grow and do this activity.

43:03 fact, I mean ch methane is worst greenhouse gas than CO. Two

43:08 . So um it's it's uh Canada is an issue in terms of contributing

43:16 the warming and whatnot. Um Any ? So we're gonna we're gonna slip

43:24 This ends the respiration slash um talk reduction potentials and so forth. So

43:33 go next into little Trophy. Okay so again we're not focusing back on

43:41 side. Okay over here we just at this section over here whether a

43:48 or anaerobic respiration. Okay. That's we're focused on the sources in

43:55 So that's a little trophy. Um and so there's kind of two

44:02 . They separate out into little trophy sort of chemo autotrophs is the same

44:08 . Okay. But then in genesis it's kind of this unique thing.

44:13 this little trophy for sure because it's . Um But you do form method

44:20 the process. Okay now um so a trophy inorganic donors. So we

44:30 get. So this is where I earlier about um excess material in the

44:39 like excess fertilizer that's used in these agricultural operations. Um So the

44:46 you remember that bottom running the triangle ? The notification reactions. Right?

44:51 we have ammonia uh oxidized to nitrite nitrate. Okay and so both of

45:01 Are acidic. Alright, nitro gas acid. These both 36 compounds.

45:06 so um if there's an excess of being formed that can affect the soil

45:12 right. And so that can be . Um Now that can occur if

45:19 have excess fertilization class. And so lazar contains of course ammonia phosphate in

45:25 and excess of ammonia. Well then you can have a lot of nitrate

45:30 acid being produced that can certainly affect soil ph So um um and and

45:37 for large values can yield that problem also can yield other problems as

45:42 See um excess. Remember that nitrogen phosphorus are limited in the environment but

45:49 you provide access to these that can an upset in the ecosystem and fertilizer

45:56 from these from these large agricultural areas contribute to that at times. And

46:03 we'll talk more about that in the unit. But but that can be

46:07 issue the because when you have an of nutrients what's going to exploit that

46:15 right because they can assimilate very quickly grow very quickly and sometimes things go

46:20 you don't want to grow because the . So um so they will definitely

46:25 advantage of of any kind of excess that are present. Um So sulfur

46:31 . So sulfur compounds like H. S. Is going to be able

46:36 s and elemental sulfur the more reduced so that they're typically what are utilized

46:41 oxidized to get energy. Uh So nature of sulfur compounds of course self

46:48 acid and product right obviously very acidic uh bacteria that do this are also

46:56 specifically. So acidic files like acid . So they'll thrive in these

47:03 Um But of course the acidity being what could be the issue.

47:06 It was your aquatic then of course potential for raising the ph or uh

47:13 the ph in these areas. That be detrimental to life. Uh Similarly

47:18 oxidation and coupled with iron, it occurs. Okay and so this can

47:23 to corrosion. So you have um example uh iron sulfide which is I

47:30 also known as a pie. I believe it was oxidized to

47:37 Okay. And the process iron is to um M. P. Three

47:44 22 plus. And so the uh course then you see the amount of

47:50 being produced as a result very Right? That that too can be

47:56 can be corrosive but also you can have the reaction of these two

48:02 Okay you can come you can have oxidation of iron. Okay this becomes

48:11 And sulfur at the same time he reduced okay to H to us.

48:20 so rather too back to FPs too that when that happens. So if

48:29 source of the iron is this is from a structure, a man made

48:36 like a girder from a bridge or pier or something like that in the

48:41 . Okay then that iron in there being used as a source and it's

48:46 oxidized. And sulfur bacteria can do . They'll oxidize the iron and reduce

48:52 sulfur H. Two S. Can be toxic as well. And so

48:57 and so as well the pyrite then the FPs too will begin to pile

49:05 on the beam. Right? So a beam in the water from a

49:09 or something. It's becoming oxidized. you'll see the pyrite will kind of

49:12 in lumps on it. Right as iron is being eaten away oxides from

49:17 the structure. Of course over time weakens and can fail obviously. So

49:24 so iron and sulfur. Where did see that those metabolism oxidation, reduction

49:28 corrosive nous and destruction of stuff. Now the so here I kind of

49:36 to just summarize the whole continuum of um sulfur and nitrogen compounds. So

49:44 looked at it both in the context respiration terminal except ear's and just now

49:50 trophy and donor as being a And so let's put them all together

49:54 see them all at once here. , so we just we just talked

49:59 this little trophies. This can be similar story where they take it in

50:03 on to it. Use it. . And that of course is the

50:07 reaction, ammonia to nitrite to Um then so we're going to the

50:15 oxidized forms, right, reduced sorry, reduced forms of coming

50:19 Then we go to the oxidized forms reduced. And that's the identification.

50:25 , dissimilar torrey process. But it's other end, Right? It's respiration

50:29 these as terminal except ear's okay. then we can close the loop.

50:35 , that's the that part of the . Right? The fixation that that

50:40 brings into back into a moment And so similarly with sulfur compounds um

50:48 reduced forms become oxidized. That's little . Okay, these can be assimilated

50:54 and used. And then uh in . That to this is also dissimilar

51:00 . Okay, Because the H two can basically be let go. But

51:05 that can also be used for little . So um the uh again on

51:13 , on this side over here, are terminal except ear's. So

51:17 both sides of the electron transport chain . Except her. Okay, so

51:26 okay, so with hydrogen trophy. , so this is technically it's little

51:34 because it's H H two is in gang. Right? So we're gonna

51:37 . It's all about oxidizing hydrogen That's little trophy. Okay, now

51:44 the weird thing about it is it's weird. But mechanics what's unusual is

51:52 Um oxidizing H2 is very it's a good energy source. Okay you get

51:58 lot of get a big negative and . two can be relatively common raw

52:08 source. Okay especially in you know and rolling pure cultures and the

52:13 Obviously you're gonna they can be around lot of metabolic activities where H.

52:17 is just a part of an end . So it can be a cheap

52:22 source. Okay so a couple of with being a really good energy

52:27 Big negative delta G. Associated with . Then it's evolved as as a

52:33 a as a metabolism and lots of bacteria. Both little tropes straighten the

52:39 and but also in Hedda tropes. e coli can actually uses this reaction

52:44 well. And you wouldn't call the and lift the trophy. Okay so

52:48 but but again hydra hydra general trophy its own is little trophy. But

52:54 just see it in hetero trophy where wouldn't normally see these other little

52:59 Okay like ammonium ammonium like notification. wouldn't see an E. Coli for

53:06 but you do see higher general Okay so just kind of a cork

53:09 with this with this metabolism with this of Annapolis. So and here's some

53:15 of how H. two oxidation is . So it can be coupled with

53:21 respiration as we see here. That's E coli uses it um uh It

53:27 be coupled with a few moderate the the Oxidation of human right to

53:36 of human destruction. Eight oxidation of two. So what we're seeing here

53:40 kind of a combination of both strictly organic right materials throughout to a combination

53:46 both inorganic and organic. This this just kind of showing you the versatility

53:51 hydrogen of trophy. Right. The types of with the trophy we looked

53:56 with other compounds don't don't Do this way that it does with H2.

54:02 , so just kind of one of unique things uh here um is the

54:09 in genesis right? It is sown Here. Okay and so um in

54:20 again it's a very potent greenhouse gas so than C. 02. It

54:27 H oxidation of H. Two energy that to be able to reduce CO

54:32 because again CO two is a poor er but the energy from here is

54:37 makes it go and um strictly anaerobic it can be offset by Mcdonnell troughs

54:44 oxidized methane. Um And so that of genesis you see very common in

54:52 environments but also in like landfills you have a lot of Sort of

54:58 material being broken down, you have lot of different metabolisms that can generate

55:02 . two. And of course you have different layers in landfill and so

55:07 will be an arab proportion in really landfills. You'll even see that have

55:12 in there Two off to offset the gas being produced. It's so vigorous

55:17 you'll often see in some big landfills flame coming up where they're where they're

55:23 rid of the methane gas but also the most. Well the well that

55:29 is the most common source of methane earth is where. Mhm. It's

55:36 another animal actually. Cows think of the towns and cattle are the wrong

55:42 Earth. And they have of course ruminants, right? They have multiple

55:47 where they digest and one of those highly uh regions. And so um

55:54 so cows are the most common source methane from that activity. So anyway

56:05 is let's see what's the next There's another question. So any questions

56:09 far? Okay. Alright so let's at this question here. Okay.

56:19 So a bacterial this is for it edit. This is really bad

56:24 A bacterial species can grow. Thank . Ain't that either? Can grow

56:32 supplied an energy source and carbon source of H two right energy source carbon

56:42 nitrate as a colonel accepted. Which not if which of the following are

56:51 to this back through Que Energy Source two Carbon Source Nitrate terminal acceptance.

57:45 think more than one of these is then you only have one choice.

57:53 , Okay. Let's see. Yes it is. Uh E all

58:06 . All the above apply. Okay it is hygienic trophy obviously it has

58:12 two being used energy sources. Um is Arabic respiration certainly because it's using

58:21 nitrogen internal except er um it's auto certainly because it says so CO two

58:28 carbon source. Right? And it represent Little Trophy as well.

58:34 the offense. Alright. And this . So e all the above.

58:39 , so let's segue then into the part of this chapter which is on

58:45 program. In fact. So take look at this and I'm gonna reset

58:53 . So which of the following among d. is not is not applicable

59:01 all double underline types of photo Mm hmm. They all progress some

59:08 of life dropping molecule or molecules Fixation Co two. They have some form

59:15 light dependent excitation of a molecule. absorption is converted to some form of

59:23 energy. So which is not applicable all of these. Mhm.

60:09 winding down 3 2, 1. . Yeah, it's the fixation of

60:17 dioxide. So remember photo autotrophs. ? They they the operative word,

60:22 is heliotrope. So they don't fix 02. Okay, so, um

60:28 certainly a C. And D do . So let's look at um little

60:35 about photo troughs. So, um the first group is probably one of

60:42 most familiar with this way for The Z scheme has been called the

60:52 using water as a donor of Uh And then the formation of oxygen

60:59 a result. So oxygen IQ we call it um the way that

61:04 do it, the way that algae it. The way that cyanobacteria do

61:08 . Okay, so this is the this this group of course is the

61:13 representative. Okay. Now and then do have in addition to nestor red

61:20 , the red boxes that sort of . The way you likely learned

61:25 And are most familiar with The two systems, et cetera. The second

61:31 is using something other than water. one of the things that differentiates

61:36 Okay, because of course water is source of oxygen when the sentence is

61:41 out. But you don't have that here. This is why we call

61:46 an oxygen in photosynthesis. No option formed. Um But the other difference

61:52 is you have both photo systems in in photosynthesis one and two. You

62:00 have one or the other? Not . And these other types. These

62:05 strictly only strictly bacteria. Do they from synthesis. And so that the

62:10 type. And so both of these and this one okay, are all

62:17 . All chlorophyll based. Okay. are all chlorophyll based type of This

62:23 an example of the header trove down . Right. So it um it

62:30 have the ability to use it to some energy but its cannot fix you

62:35 . Right. That's the key. then the last group is released different

62:41 the other ones. Okay. Because is a type that's not core field

62:46 . Okay. And so there's no pigments or anything related to it in

62:51 type. It's very different. But is a light driven proton pump.

62:58 . That just that is connected to http sentence. Okay. So it

63:02 make a tPS this way but being head of trophy it uh it

63:09 organic compounds. It doesn't fix the . Okay. And so this is

63:13 the one we'll look at first is system here. Okay, that's probably

63:18 most the most ancient in terms of light as an energy source is probably

63:23 first one that evolved I think might be one of the first ones that

63:27 . Okay. And so um so look at that here. Okay,

63:33 not quite jumping on. So this kind of just a the summary of

63:38 what are what's common to most Okay. In terms of photosynthesis.

63:44 obviously using light capture and you can molecules that are but that didn't do

63:52 . So basically typically for filled and based molecules but there are non floor

63:57 types as well. They can do . Okay, so um the common

64:04 all types. Right. So you're have some type of light absorption is

64:09 accompanied by some excitation of a Okay. And then um and then

64:16 course you're gonna have a membrane membranes of all because you are going

64:19 be generated with protons. Check so and of course the membrane can be

64:26 full of these pictures. Okay. then uh light reception. Right.

64:31 you have some way you capture the have exploitation but then there has to

64:35 translated into energy production. Okay. so of course there's that photo phosphor

64:42 making a tPS. Okay. Now what's not common to all systems is

64:51 tosses. Okay. And so forth reactions. So for example like

64:58 It's common. Okay. That's what's to a plant or analogy or center

65:04 . Okay. H two S is common one for oops human whispering.

65:14 H two s. Is another one see with an oxygen tank system.

65:19 it's bacterial types. We that are little different. Use that as a

65:23 . Um but and so the stripping from these components is light driven.

65:31 ? That's what we call policies but it's not everything. But these non

65:39 based systems don't have that. So they're they're the exception. They

65:42 have a colossus reaction. Right? a very different type of photosynthesis.

65:49 , so let's look at that And so bacterial adoption. So you

65:55 have adoption may ring a bell in head If you take an eight MP

66:01 or intro bio um I believe they about it in the context of

66:08 And so adoption is used um rods cones. I thought this a long

66:14 ago, I can't quite remember it . But their adoptions involved in the

66:17 capture in terms of how you perceive . Okay. There's some evidence that

66:23 of some some relationship there between the uh this material adoption and structurally at

66:28 between the two types. But the use here is of course for

66:34 capture as well. Ah and then then company that to proton pumping.

66:40 , so the reduction uh molecule of there's a protein as you see

66:48 the in red right? The part that chain and then in the middle

66:55 linked to what's called right now. , so right now molecules bonded to

67:02 protein and that's the light absorbing part the protein. Right? This is

67:08 now. So it absorbs light. , there's a shift at this bond

67:15 . Okay. And it basically twists group. We see the light seen

67:20 attached attached to it right now. when that shifts the light absorption then

67:27 moves the whole protein as well. , because they're both made. So

67:31 now absorbs light and shifts and the shifts shape as well. But that

67:38 in shape is linked to a protons or protons being pumped out.

67:47 so his light's absorbed chicken protein pumping out. Okay, so what you're

67:54 basically is a proton gradient as a . Okay. Ah Here And then

68:00 course that's coupled to an eight Okay. And for energy production now

68:09 type of bacteria that do this are . Hello file. Hello?

68:13 Are Kiev um bacterial types. It's rodeo adoption. Um believed to have

68:21 gene transfer between the two groups. how it acquired this. But the

68:29 light absorbed is green light. so the bacteria appear so in water

68:36 you see this activity will have like purplish color to it. Okay.

68:43 And that's because the light absorption you green light, you actually reflect purple

68:47 . Okay. And so they often these things purple patches where we have

68:53 membranes full of these types of uh adoption molecules absorbing light. And so

68:59 purple color again is what's being reflected the green light. Um But it

69:04 a it's a non chlorophyll based completely from what we're gonna talk about next

69:10 the next time. But the but no no photosynthesis reaction going on.

69:16 . It's just simply absorption of photons light. There's no it's not like

69:22 electron transport chain and electrons feeding or or photo systems, it's just a

69:28 retinal absorbing light shape change, protons out. As simple as that.

69:34 , so that's what I mean. it's very different from the other

69:37 Okay. But believed to be very and likely maybe one of the first

69:41 of photosynthesis on earth. Um, any questions. Okay. That's what

69:51 gonna do today. So we're gonna up full of trophy on monday when

69:56 get back, you know, a plus a week and a half.

70:00 . So, um, I hope get to take some time off next

70:08 . We will see you then.

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