hello bisque 132 this is the beginning of recorded lecture one five uh still still in this chapter on protists and it is admittedly a long one uh but we're we're gonna finish it up in this recorded lecture so we've been going through these six super groups of eukaryotes we've only got two left but they're two of the bigger ones uh so let's turn our attention now to the biggest of these a super group called chrome alveolata some chrome alveolata members are photosynthetic although some members have lost to this ability so the the ancestors to this group were photosynthetic but this is another confounding you know thing that can happen evolutionarily uh not everyone in this group has the ability to do photosynthesis uh we're gonna see this in in other more relatable groups later on you know birds that have lost the ability to fly uh or vertebrates that have lost some or all of their four limbs uh yeah evolutionarily this group is photosynthetic but not everyone in this group does it because they've lost it evolutionarily now this is such a large group that you could actually divide this super group even further into two other clades uh alveolates and stray menopils let's do this alveolates next so this is under the supergroup of chrome alveolata and this if you want to be generic you know i talked about the domain kingdom phylum all that stuff but uh sometimes you could just call something a clade uh and that's just the only way to do it this clade alveolata or alveolites includes several other groups so we're under both of these umbrellas again i find this to be um perhaps a useful visual if you're trying to take in some of this information that yeah dinoflagellates are alveolates they're also chrome alveolata they're also eukaryotes so whatever you need to look at to make this click with your brain so okay what are dinoflagellates well dinoflagellates are mostly marine meaning they live in salt water they're plankton so we're going to see plankton come up several times in this chapter and other chapters plankton is not a species of thing it's not a group of thing plankton is a lifestyle so the key terms define plankton as a diverse group of mostly microscopic organisms that drift in marine and freshwater systems and serve as food for larger aquatic organisms the key part of that definition is drift plankton are organisms that go with the flow that don't really actively swim from place to place just go where the movement of water takes them and again most plankton is microscopic but there's some uh macroscopic plankton as well so dinoflagellates have this this lifestyle this planktonic lifestyle as it's called and there are a few interesting notable members uh some of them uh produce toxins are responsible for this uh red tide algal bloom this uh photo here taken from florida very dangerous to be in or near this water it looks very beautiful but well actually it looks kind of grim like it's filled with blood or something but these are toxins produced by dinoflagellates don't want to be anywhere near that on a much lighter note some dinoflagellates are bioluminescent uh meaning they they produce their own light so here's a cool bay showing these uh you know washing up against the shore there are other cool pictures and videos of these sometimes their bioluminescence is a defense mechanism so they'll light up when they are disturbed uh and so there are cool videos of boats going through waters with these dinoflagellates and leaving behind them a wake of bioluminescence really cool stuff so these are just some of the notable members some produce toxins in water what we call red tides some are bioluminescent and there's another notable member or group of members within dinoflagellates some are photosynthetic partners of corals so we will see this exact slide again when we talk about animals and invertebrates but corals are part of a group of uh animals uh not protists but they have a symbiotic relationship with these algae these protists these dinoflagellates allowing them to effectively do photosynthesis so the protists the dinoflagellates do photosynthesis and the coral you know gives them a safe place to to live so they're not just floating around uh and easy prey for other things in the marine ecosystem so i can come back to this later when we talk about animals but important to know now some dinoflagellates are the the other half the non-animal half of this uh of this thing the photosynthetic partners of corals okay so that was dinoflagellates another group within within chromia alveolata within alveolates um is ap complexions and uh you know you're in for a wild ride when the group has complex as part of its name this includes uh the parasite that causes malaria and i mentioned near the top of this chapter that a lot of protests have complex life cycles and boy is this an example of that um we are not going to list these 10 steps we are not going to uh to memorize all this stuff but i i put up this slide to show you just how complicated things can be that you have stages of the mosquito and you have multiple your fertilization events and mitosis and you have different stages here this only takes place in the mosquito uh so the the parasite needs to be in the mosquito it's not just spread from mosquito is a convenient way to move it around it has to complete several stages of its life cycle within the mosquito and then within the human you've got other types of division and you've got different schizon ring stages and other types of infection and going different parts of the body and then making it back to the mosquito it's complicated so this is you know just interesting to look at but here's what i want you to take from this members of this group ap complex ants are all parasites uh with complex life cycles and and you should definitely know the group here responsible for malaria because malaria has a huge impact on global public health plasmodium spp i think this is the first time uh we've come across this so we talked in the first chapter uh in this course the genus and species naming convention the binomial nomenclature plasmodium here of course being the genus and spp period this doesn't mean a specific species when you see this it means several different species within this genus so the abbreviation just means several species uh plasmodium falciparum is one that comes to mind but there are several species which can cause malaria so plasmodium spp you see that you should associate that with malaria okay then there's one last alveolate a group called ciliates uh and again the name says a lot about them they've got cilia right in the name they are covered in cilia here we go so there's a microscope image again they're single celled so they're obviously very small and yeah here's a cartoon that shows this a little more clearly the cilia that covers their body and uh yeah they swim around using the cilia and uh and they eat bacteria remember i told you that this group as a whole was you know photosynthetic but uh obviously you know some have lost this ability malaria parasites are not photosynthetic and and these ciliates are not photosynthetic either so the ciliates are covered in cilia and uh they're heterotrophs that eat bacteria so that was half of chrome alveolata these three uh the other clade within this clade is stramino piles and if we want to talk about their distinguishing feature they have hairy flagella which i mean there it is so there's a flagellum with these the hairs attached to it it's a weird phrase but yeah it's a distinguishing feature of members of this this clade stramino piles within the super group chrome alveolata so there are several streaming piles uh so this this group includes several other groups one of which is called diatoms so diatoms are also photosynthetic um and very beautiful looking if i'm being honest here lots of cool unique shapes uh you know triangles circles ovals whatever you'd call this spiraled a star that's very cool um unique shapes here to go to another image here's another image just showing how you know the diversity of these different shapes that they can have they are photosynthetic they are planktonic and they have unique complex shells made of silica as a fun side note if you're into uh to crime drama or crime shows or things like that the these shells are so unique different bodies of water uh have different populations of diatoms with different with different unique shapes so there have been in tv shows but also in real life uh cases where you know a victim's body was found drowned and you know they they looked at the diatoms of the lungs and found that oh this this person must have been drowned in this lake in specific uh because the diatoms from that lake had these unique shapes so sort of piecing together the crime in that way so that just fun side note but uh there are unique complex shells of silica associated with these photosynthetic diatoms uh another group of stramino piles is golden algae this is another photosynthetic plankton uh instead of having shells uh what's special about the golden algae and so they can form branching colonies so this isn't really a multicellular organism it's a bunch of cells that are you know growing together to form a colony but it's definitely something that diatoms you know don't do completely single celled here so golden algae photosynthetic plant and deform branching colonies now uh a very interesting stream that oppai i'll talk about next is brown algae and i think this is very interesting because this is one of those protists that most people don't know is a protist brown algae is kelp or sometimes called seaweed i think most people would look at this stuff whether it's you know washed up on a beach or whatever and identify it as a plant because it looks a lot like a plant i mean it's it's photosynthetic it's green more or less kind of greenish brown but it's it's more or less green it's got these quote-unquote leaves uh that has to do photosynthesis it looks just like a plant evolutionarily however the way it does photosynthesis and everything it's not a plant this is another example of convergent evolution if you're doing photosynthesis and you're a multi-cellular organism having this flat blade-like structure a quote-unquote leaf is just a really good way to capture sunlight so plants evolved leaves because it's a good way to do it and independently these brown algae have a very similar body form because it's a good way to do photosynthesis so uh brown algae also known as seaweed also known as kelp are photosynthetic which isn't unique but they're multicellular it's been a while since we've seen a multi-cellular protist i said at the top most of them are single-celled and hopefully that's been that's been shown as i've gone through the chapter but this is one of the rare multi-cellular protests and yeah they are superficially similar to plants that's a way to say that and okay finally in stramino piles uh one last group here uh oo my seats uh so oo my seats are saprobes or parasites so we know what a parasite is a saprobe needs to be defined uh it's in the key terms an organism that derives nutrients from decaying organic matter and again that's sort of the mo of a fungus uh these things uh are superficially similar to fungus meaning they look like a fungus here's an example of an oo my seat uh yeah gross looking mold um i've been assured there's a grasshopper underneath all this uh apparently a dead grasshopper being um you know being broken down and nutrients absorbed from it underneath this this mess of stuff uh this is another one of those protists that before genetic sequencing and sequence alignment technology came along it was uh it was called a fungus it was part of uh kingdom fungi uh but anyway they've got the fungi lifestyle and sap robes or some of them are parasites they look like a fungus and they have a very famous member um this is uh well this is a potato but it's a really gnarly messed up potato because it has been infected by phytophthora infestands that's quite the mouthful remember there's no spelling required on my multiple choice exams uh more commonly known as potato blight so it doesn't look like much uh but this protest had a huge impact uh on the world really it's responsible for the the great famine in ireland from 1845 to 1852 i think about a million deaths and and maybe two million irish who fled the country to for other parts of the world huge economic and political repercussions this is not a history class but uh you know if you take a history class a world history class this will come up and it's fun to note that it's not a fungus that was responsible for this like most people would uh would kind of assume or look at this is a protist that's responsible for this blight uh on the potatoes so phytophthora infestans potato blight it's one of these oo my seats which is in the group of stramito piles which is in the super group of chrome alveolata all right one last group here almost finished with this uh this is the super group called excavata kind of a weird name ex cavada these are single-celled organisms um they are named for a feeding groove that's present on their their cells that someone thought it looked like this this groove had been excavated from the side and so here's a cartoon we'll see some microscope images but it's easier to see in the cartoon there's a nucleus and there's a flagellum uh and yeah here's the the feeding groove here uh again someone thought it had been it looked like it had been excavated from the side of the cell hence the name excavator just you know something to help you remember the name even though it's kind of a weird stretch but that's what they're that's what they're named for excavator includes a group called diplomonads and uh okay just again the names often provide clues about things so don't worry about monad but but die should mean something to you uh die means two so there's gonna be something about these things that they have two of and looking at these under the microscope should be pretty apparent the thing they have two of is nuclei yeah these kind of look like eyeballs but remember this is a single celled organism this is a nucleus and this is a nucleus so diplomats they have two nuclei uh and actually if you look more closely at these if you you know sequence these genomes and then examine them genetically they're actually not identical so these diplomats have two non-identical haploid nuclei uh which is weird i mean we have you know two copies of each gene we just put them in a single diploid nucleus the reason why they keep their non-identical copies and two separate haploid nuclei is not well understood there's another more bizarre thing about them they have reduced mitochondria so if you remember mitochondria or one of those you know basic fundamental things that all eukaryotes have um they don't have them uh and it's not that these are the the most ancient most basal eukaryotes there are uh they've they've reduced the function of their mitochondria they've essentially lost most of this organelle and again we'll see this in later chapters as well this is not unlike uh birds that have lost the ability to fly like penguins or or things like that so they have reduced mitochondria called mitosomes and a good member you know just an interesting member of note in diploma ads is giardia lamblia this is what we've been looking at here again not much to really look at some flagella whatever uh giardia lambly is responsible for uh hikers diarrhea so if you're going hiking in the mountains and you see a beautiful clear stream of water uh it may look beautiful and clear but you know a deer may have pooped in it upstream and there may be giardia in there you drink that and and you may be uh suffering from the same thing that that that deer did so anyway giardia lambly a notable number of uh of diplomats so okay there are some other uh excavator here other than diplomats one another group is parabasalids and they've got the same thing going on reduced mitochondria and again the reason for this uh is not well understood why they would you know go backwards from this evolutionary innovation that was uh fundamental to eukaryotes and sort of reduce their their function not well understood their cells are not too much to to look at um you can kind of see the feeding groove there um they have flagella to swim around and this thing at the tip uh might look like another flagellum it's actually a structure called the axo style which is used for attachment sort of stabbing into something and then keeping it in place so parabasalites have flagella and an axo style for attachment and yeah attaching themselves to things might make you think that they would be very good parasites that would be a good conclusion uh a notable number of parabasalids is trichomonas vaginalis uh responsible for trichomoniasis a fairly common sexually transmitted infection uh it's not terribly harmful on its own asymptomatic about 50 of the time but it can increase susceptibility to other sexually transmitted infections like hiv and can complicate childbirth and pregnancy and so it's pretty notable despite vaginalis being the species name men can contract this infection as well um but not all parabasalids are parasites another notable member not you know for us but another notable member of parabasalits is tricho nympha there's the spp again so several species here uh trichonympha uh they live in the gut of the termite and digest cellulose so again the single-celled organism is you know not really anything all that interesting uh but this is the power behind uh behind the termite uh we're gonna see in later chapters when we talk about the digestive system uh no animal can really digest cellulose can really break down leaves or grass or wood any animal that makes its living eating that sort of plant matter you know whether it's a cow or a rabbit or a termite every single animal that does that has to have some partner actually breaking down the cellulose for them and in this case uh the termites are using this these trichonympha spp species uh in their gut to digest this cellulose in the plant matter uh that they that they are consuming okay so these were both parabasalids uh moving on more ex cavada uh the next group to talk about is euglenozoins zoens again they have flagella that's not really special here there's some flood gel i'm sticking out here but um there is something else if we look closely at this so this this reservoir here this is essentially a mouth so they use the flagellum and there's there's another shorter flagellum in here as well just sort of reach out and grab prey bacteria and bring it into their mouth to eat so these things are heterotrophs they're swimming around they're eating bacteria but if you look you know all the other things labeled here whoa there's also a chloroplast so these things are eating bacteria they're also doing photosynthesis these are and i defined this at the top of the chapter maybe you've been waiting for it to come up uh most euglenozoins are freshwater mixotrophs so there's the mixotroph term uh they're hot heterotrophs and autotrophs very cool uh at least cool to me but not all of them are freshwater mixotropes i did say most uh there is a very notable parasite within this group euglenozoa so some of them are parasites the notable number is uh trypanosoma bruciae responsible for african sleeping sickness there's the trypanosome here in single-celled organisms so not that interesting and whoa here's the infection cycle so again i think malaria has got it beat as far as complexity goes but this is another thing that seetsy fly is spreading it not a mosquito but you know using the titsy fly you know infecting the human uh this is uh a very horrible disease to have uh causes a lot of neurological symptoms including issues with sleep regulation hence the name sleeping sickness uh but yeah you should uh be aware that trypanopsoma bruce eye is responsible for african sleeping sickness and it's a parasite uh that is the in the group euglenozo so it's not just fresh water mixotrops it's uh some nastier stuff as well so okay we're we're finally done we finally finished out uh this this whole table here i mean obviously we skipped plants animals and fungi will come to those in their due time but we have finished going through all the groups of protists uh there's just there's just one last thing that i want to point out um and this is kind of a note uh sometimes single-celled heterotrophic protests are called protozoa so obviously this word protozoa doesn't have any evolutionary meaning it's just a catch-all umbrella term i mean i guess protists already kind of a catch-all umbrella term uh but it's an even more uh informal umbrella term uh that you know scientists used to and sometimes still do that's why i'm pointing this out to you used to describe uh any of this stuff so all these things should look familiar to you the the silly it's the choanoflagella that's amoeba of different shapes and sizes a single celled protist that is heterotrophic can be called a protozoan so again the field is moving away from this term because it doesn't have any evolutionary significance um it's very arbitrary just to define what is and that isn't here from an evolutionary standpoint but i want you to be equipped with this knowledge because you may see this in other courses or other sources single cell heterotrophic protests sometimes applied to to this term protozoa protozoans okay now this is the end of the chapter on protists and it makes for a perfect cutoff for the end of this lecture this uh recorded lecture is a bit shorter than most of the others but man this one and the last one have just been packed with information so i think it's fine for this one to be a little bit shorter this is the end of recorded lecture one five and you'll note this is also the end of the material uh that applies to exam number one so this is the cut off for you know where exam number one material will end uh at the end of this protist chapter