VirusesVirusesLiving or non-living? This is debatable!Living or non-living? This is debatable!

Living Thing? Viruses can reproduce.Living Thing? Viruses can reproduce.

Non-living thing? Viruses can only show characteristics Non-living thing? Viruses can only show characteristics of a living thing (reproduce) inside a host cellof a living thing (reproduce) inside a host cell

Viruses are infectious particles made only of a strand of Viruses are infectious particles made only of a strand of DNA or RNA surrounded by protein coat.DNA or RNA surrounded by protein coat.

Viruses are small or very small (50-200 nm) and cannot Viruses are small or very small (50-200 nm) and cannot be seen with a light microscope (you need an electron be seen with a light microscope (you need an electron microscope). microscope).

Some scientists consider viruses as complex chemicalsSome scientists consider viruses as complex chemicals

Common Viral DiseasesCommon Viral DiseasesCommon coldCommon cold

Influenza (flu), such as H1N1 (swine flu)Influenza (flu), such as H1N1 (swine flu)

SARSSARS

Chicken poxChicken pox

EbolaEbola

MeaslesMeasles

MumpsMumps

PolioPolio

Mad-cow diseaseMad-cow disease

HIVHIV

West NileWest Nile

HPV (Human papillomavirus)HPV (Human papillomavirus)

HerpesHerpes

RabiesRabies

HepatitisHepatitis

Viral InfectionsViral Infections2 types:2 types: Lytic infection Lytic infection – host cell – host cell

bursts and releases new bursts and releases new viruses that infect more viruses that infect more host cells host cells

Lysogenic infectionLysogenic infection – – virus combines it’s DNA virus combines it’s DNA into the host cell’s DNA into the host cell’s DNA but does not produce but does not produce viruses (dormancy stage) viruses (dormancy stage) but eventually viruses are but eventually viruses are porduced.porduced.

Questions 1-2, p 551Questions 1-2, p 5511.1. Name and describe the main parts of a typical virus.Name and describe the main parts of a typical virus.

- capsid: protein shellcapsid: protein shell- genetic material: single-stranded or double-stranded DNA or RNAgenetic material: single-stranded or double-stranded DNA or RNA- Some viruses have a lipid envelope covering the capsidSome viruses have a lipid envelope covering the capsid

2.2. What are the differences between a lytic infection and a lysogenic What are the differences between a lytic infection and a lysogenic infection? Include the effects of each type of infection on the cells of infection? Include the effects of each type of infection on the cells of the host organism in your answer.the host organism in your answer.

- Lytic infection: virus replicates many times, producing many Lytic infection: virus replicates many times, producing many offspringoffspring

- Lysogenic Infection: virus integrates into the host cell’s DNA, with Lysogenic Infection: virus integrates into the host cell’s DNA, with viral genes passed to the host cell’s daughter cells during mitosis. viral genes passed to the host cell’s daughter cells during mitosis. Lytic infection destroys the host cell after viral replication and Lytic infection destroys the host cell after viral replication and release of offspring, whereas lysogenic infection generally causes release of offspring, whereas lysogenic infection generally causes no initial harm to the cell, though it can alter some of the cell’s no initial harm to the cell, though it can alter some of the cell’s traits.traits.

Questions 3-4, p551Questions 3-4, p5513.3. Researchers studying infection can often grow Researchers studying infection can often grow

bacteria more easily than they can grow viruses. bacteria more easily than they can grow viruses. What conditions must scientists provide for viruses to What conditions must scientists provide for viruses to multiply?multiply?

- In order to replicate, viruses need living cells they can infectIn order to replicate, viruses need living cells they can infect

4.4. A wart is caused by a virus that may lie dormant for A wart is caused by a virus that may lie dormant for years before any symptoms appear. Does this years before any symptoms appear. Does this resemble a lytic or lysogenic infection? Explain.resemble a lytic or lysogenic infection? Explain.

- Lysogenic. It is characterized by a virus that lies dormant.Lysogenic. It is characterized by a virus that lies dormant.

Question 5, p551Question 5, p5515.5. If the virus is a foreign invader, how is it If the virus is a foreign invader, how is it

possible for the proteins of its capsid to match possible for the proteins of its capsid to match the receptors on the host cell’s surface? the receptors on the host cell’s surface? Consider natural selection in your answer.Consider natural selection in your answer.

- Over time, viruses that happened to have the right Over time, viruses that happened to have the right protein “key” would survive and pass on these protein “key” would survive and pass on these traits to their viral offspring. Viruses without the traits to their viral offspring. Viruses without the right proteins would not be able to successfully right proteins would not be able to successfully infect the host and would probably become extinct.infect the host and would probably become extinct.

Questions 1-3, p554Questions 1-3, p554

1.1. Name and describe two infectious viruses and a Name and describe two infectious viruses and a body’s first defense against infection.body’s first defense against infection.

- Common cold, flu, SARS, HIV, chicken pox.Common cold, flu, SARS, HIV, chicken pox.- The skin is the body’s first defense against infection.The skin is the body’s first defense against infection.

2.2. Briefly describe how a vaccine can prevent Briefly describe how a vaccine can prevent some viral infections.some viral infections.

- A vaccine is made from a weakened pathogen or parts - A vaccine is made from a weakened pathogen or parts of a virus. When given, it stimulates the host’s own of a virus. When given, it stimulates the host’s own immune system, preparing it for future infections by immune system, preparing it for future infections by the real virus.the real virus.

Questions 3 – 4, p554Questions 3 – 4, p5543.3. If a vaccine is in short supply, why is it often If a vaccine is in short supply, why is it often

recommended that older adults and children get recommended that older adults and children get vaccinated first?vaccinated first?

- The immune system of older adults and The immune system of older adults and children are often weaker than those of the children are often weaker than those of the rest of the population, so they are more likely rest of the population, so they are more likely to become infected than a healthy person who to become infected than a healthy person who is not very young or very old. is not very young or very old.

4.4. Why might getting a flu vaccination sometimes Why might getting a flu vaccination sometimes cause you to get a mild case of the flu?cause you to get a mild case of the flu?

- because you may be getting a weakened strain because you may be getting a weakened strain of live virus in order to build up your immune of live virus in order to build up your immune system.system.

Question 5, p554Question 5, p554

5.5. People infected with HIV (the virus that People infected with HIV (the virus that causes AIDS) can become unable to fight causes AIDS) can become unable to fight off infections by organisms that normally off infections by organisms that normally do not harm people. Why is this so?do not harm people. Why is this so?

- HIV affects the immune system of an infected - HIV affects the immune system of an infected person, making him or her susceptible to person, making him or her susceptible to organisms that are normally harmless. organisms that are normally harmless.

Prokaryotes (Bacteria & Archaea)Prokaryotes (Bacteria & Archaea)

Both groups are prokaryotic (lack a nucleus and Both groups are prokaryotic (lack a nucleus and organelles)organelles)

Divided up based on need for oxygen (ODivided up based on need for oxygen (O22):):A.A. obligate anaerobesobligate anaerobes

- cannot live in presence of Ocannot live in presence of O22

- Some produce methane gasSome produce methane gas- Live in marshes, lake bottoms, or digestive tracts of Live in marshes, lake bottoms, or digestive tracts of

herbivores like cows, deer and sheepherbivores like cows, deer and sheep

B.B. obligate aerobesobligate aerobes- Need ONeed O22 or will die or will die

- Many common pathogens like tuberculosis and leprosyMany common pathogens like tuberculosis and leprosy

C.C. Facultative aerobeFacultative aerobe- Can survive with or without O- Can survive with or without O22

Bacteria and archaea are similar structurally but Bacteria and archaea are similar structurally but differ in genetics and biochemistrydiffer in genetics and biochemistry

Both groups are small single-celled organisms Both groups are small single-celled organisms with a cell wall and cell membranewith a cell wall and cell membrane

Archaea have many shapes, bacteria have 3:Archaea have many shapes, bacteria have 3:a.a. BacilliBacilli – (rod-shaped) – (rod-shaped)

b.b. SpirochetesSpirochetes - (spirilla or spiral-shaped) - (spirilla or spiral-shaped)

c.c. CocciCocci - (round or spherical) - (round or spherical)

Archaea and bacteria move by gliding or Archaea and bacteria move by gliding or using flagella (whip-like tail used for using flagella (whip-like tail used for locomotion) or pili (smaller locomotive locomotion) or pili (smaller locomotive structures)structures)

Typical prokaryote structure:Typical prokaryote structure:

Archaea and bacteria differ their cell wall, Archaea and bacteria differ their cell wall, flagella and plasma membrane compositionflagella and plasma membrane composition

4 main groups of Archaea:4 main groups of Archaea:1.1. Methanogens – produce methaneMethanogens – produce methane

2.2. Psychrophiles – live in cold temperaturesPsychrophiles – live in cold temperatures

3.3. Halophiles – live in salty environmentsHalophiles – live in salty environments

4.4. Thermophiles – live in extremely warm/hot Thermophiles – live in extremely warm/hot temperaturestemperatures

Bacteria – two main groups:Bacteria – two main groups:1.1. Gram Positive – stain purple with a Gram stainGram Positive – stain purple with a Gram stain

2.2. Gram Negative – stain red in a Gram StainGram Negative – stain red in a Gram Stain

Gram Positive / Negative BacteriaGram Positive / Negative Bacteria

Bacteria – benefits to humansBacteria – benefits to humansBacteria help humans and other animals in their Bacteria help humans and other animals in their digestive tract:digestive tract: Cattle (and other ruminants) use bacteria to breakdown Cattle (and other ruminants) use bacteria to breakdown

their foodtheir food Human use bacteria in their intestinal track to produce Human use bacteria in their intestinal track to produce

vitamins and other substancesvitamins and other substances

Many foods produced by fermentation by bacteria:Many foods produced by fermentation by bacteria: yogurt, cheeseyogurt, cheese picklespickles sauerkrautsauerkraut vinegar, soy saucevinegar, soy sauce

CyanobacteriaCyanobacteria – produce huge amounts – produce huge amounts of oxygenof oxygen

Nitrifying bacteriaNitrifying bacteria (in the soil) fix nitrogen (in the soil) fix nitrogen from the atmosphere into usable form for from the atmosphere into usable form for plantsplants

BioremediationBioremediation – uses microbes and – uses microbes and other living things to break down or other living things to break down or destroy pollutants. Bacteria are a key destroy pollutants. Bacteria are a key organism is biological decay organism is biological decay (biodegradation)(biodegradation)

Bacterial DiseasesBacterial Diseasesacneacne

tuberculosistuberculosis

anthraxanthrax

Lyme diseaseLyme disease

tetanustetanus

gangrenegangrene

botulism (as well as other forms of food poisoning, such as botulism (as well as other forms of food poisoning, such as salmonella)salmonella)

tooth decaytooth decay

strep throat, ear infections, flesh-eating diseasestrep throat, ear infections, flesh-eating disease

bacterial pneumoniabacterial pneumonia

STI – syphilis, Chlamydia, etc…STI – syphilis, Chlamydia, etc…

Questions 1-3 page 558Questions 1-3 page 5581.1. What are the three most common shapes of What are the three most common shapes of

bacteria?bacteria?- rod, spiral and sphererod, spiral and sphere

2.2. Why are bacteria and archaea classified into Why are bacteria and archaea classified into different domains?different domains?

- Archaea are biochemically and genetically different from Archaea are biochemically and genetically different from bacteriabacteria

3.3. Prokaryotes will take up foreign DNA. How is this Prokaryotes will take up foreign DNA. How is this characteristic used in genetic engineering?characteristic used in genetic engineering?

- Pieces of genes can be inserted into the genetic material Pieces of genes can be inserted into the genetic material of prokaryotes so that they will make the protein products of prokaryotes so that they will make the protein products encoded in the genes or copies of the genes themselves.encoded in the genes or copies of the genes themselves.

Question 4-5, p558Question 4-5, p5584.4. Scientists estimate that only 1 percent of prokaryotes can Scientists estimate that only 1 percent of prokaryotes can

be grown in the lab. What does this suggest about our be grown in the lab. What does this suggest about our knowledge of bacteria and archaea?knowledge of bacteria and archaea?

- We do not know much about prokaryotes. Our We do not know much about prokaryotes. Our understanding of prokaryotes will likely change as understanding of prokaryotes will likely change as scientists learn more about prokaryotes that have not scientists learn more about prokaryotes that have not been able to be cultured, or grown, in the lab.been able to be cultured, or grown, in the lab.

5.5. Prokaryotes multiply by binary fission, which simply Prokaryotes multiply by binary fission, which simply divides a cell in two. Why are mutations and conjugation divides a cell in two. Why are mutations and conjugation important for natural selection in prokaryotes?important for natural selection in prokaryotes?

- Binary fission produces no variation, but mutations and Binary fission produces no variation, but mutations and conjugation do. Natural selection requires variation in a conjugation do. Natural selection requires variation in a population.population.

Question 6Question 6

6.6. Bacteria in your mouth convert foods Bacteria in your mouth convert foods containing sugar and starch into acids that can containing sugar and starch into acids that can then cause cavities in your teeth. These then cause cavities in your teeth. These bacteria will be present even if you brush your bacteria will be present even if you brush your teeth, floss, or use mouthwash. So why are teeth, floss, or use mouthwash. So why are these hygiene habits so important?these hygiene habits so important?

- Brushing teeth is important to keep the population Brushing teeth is important to keep the population of these bacteria down and to remove the food that of these bacteria down and to remove the food that the bacteria convert into acid.the bacteria convert into acid.

Questions 1-3, p561Questions 1-3, p5611.1. Describe two ways bacteria provide nutrients to humans.Describe two ways bacteria provide nutrients to humans.

- Bacteria in our bodies make vitamins that we absorb, and - Bacteria in our bodies make vitamins that we absorb, and some bacteria are needed to make foods that we eat, some bacteria are needed to make foods that we eat, such as soy and dairy products.such as soy and dairy products.

2.2. What are two roles prokaryotes play in the cycling of What are two roles prokaryotes play in the cycling of elements in an ecosystem?elements in an ecosystem?

- producing oxygen through photosynthesis, fixing producing oxygen through photosynthesis, fixing nitrogen, decomposing other organismsnitrogen, decomposing other organisms

3.3. Think of an example in which the use of bioremediation Think of an example in which the use of bioremediation either has improved the environment or has the potential to either has improved the environment or has the potential to do so.do so.

- Cleaning up industrial accidents, sewage and other Cleaning up industrial accidents, sewage and other waste.waste.

Questions 4, p561Questions 4, p5614.4. How do prokaryotes lend to stability to an How do prokaryotes lend to stability to an

ecosystem?ecosystem?- Prokaryotes lend stability to an ecosystem through - Prokaryotes lend stability to an ecosystem through

their role as decomposers. Other organisms rely their role as decomposers. Other organisms rely on prokaryotes for nitrogen and other compounds on prokaryotes for nitrogen and other compounds that are broken down through prokaryote that are broken down through prokaryote metabolic activity. Some prokaryotes also help the metabolic activity. Some prokaryotes also help the stability of an ecosystem by releasing oxygen into stability of an ecosystem by releasing oxygen into the environment during photosynthesis.the environment during photosynthesis.

Question 5, p561Question 5, p5615.5. Prokaryotes in cow intestines produce more methane if Prokaryotes in cow intestines produce more methane if

the cow is fed a diet high in grains rather than grass. the cow is fed a diet high in grains rather than grass. Some scientists propose that overfeeding grain to cows Some scientists propose that overfeeding grain to cows contributes to global warming. How did these scientists contributes to global warming. How did these scientists arrive at this hypothesis, and how could it be tested?arrive at this hypothesis, and how could it be tested?

- Students can infer that the amount of methane Students can infer that the amount of methane produced by the intestines of a grain-fed cow can be produced by the intestines of a grain-fed cow can be compared to that produced by a grass-fed cow, perhaps compared to that produced by a grass-fed cow, perhaps by measuring concentrations of methane in closed by measuring concentrations of methane in closed environments after cows have fed and lived inside them environments after cows have fed and lived inside them for some time. The effect of methane concentration on for some time. The effect of methane concentration on the heat retention of the atmosphere can also the heat retention of the atmosphere can also presumably be tested in a small, enclosed space that is presumably be tested in a small, enclosed space that is open to sunlight.open to sunlight.

Domain EukaryaDomain Eukarya

all are eukaryotic (possess a nucleus all are eukaryotic (possess a nucleus and organelles)and organelles)

4 kingdoms:4 kingdoms: Kingdom ProtistaKingdom Protista Kingdom FungiKingdom Fungi Kingdom PlantaeKingdom Plantae Kingdom AnimaliaKingdom Animalia

Kingdom ProtistaKingdom ProtistaEukaryotic (cells have a nucleus and organelles)Eukaryotic (cells have a nucleus and organelles)

Mostly unicellular, some are colonialMostly unicellular, some are colonial

Most are microscopic, some are huge (slime molds)!Most are microscopic, some are huge (slime molds)!

Divided into three informal categories, based on Divided into three informal categories, based on their food-gathering method:their food-gathering method: Animal-like protists: eat (ingests) their food Animal-like protists: eat (ingests) their food

(heterotrophic)(heterotrophic) Plant-like protists: make their own food by Plant-like protists: make their own food by

photosynthesis (autotrophic)photosynthesis (autotrophic) Fungal-like protists: absorb their food Fungal-like protists: absorb their food

(heterotrophic)(heterotrophic)

Animal-like ProtistsAnimal-like ProtistsSometimes called “zooplankton” or “protozoa”Sometimes called “zooplankton” or “protozoa”

4 phyla:4 phyla:

1.1.ZooflagellatesZooflagellates (Phylum Zoomastigophora) (Phylum Zoomastigophora)- Have flagella to move around (whip-like structures)Have flagella to move around (whip-like structures)- TrypanosomaTrypanosoma causes African Sleeping Sickness, causes African Sleeping Sickness,

which is transmitted by tse tse flywhich is transmitted by tse tse fly

2.2.SarcodinesSarcodines (Phylum Rhizopoda) (Phylum Rhizopoda)- Have pseudopods (“false feet”) to move aroundHave pseudopods (“false feet”) to move around- Engulfs food by surrounding it with their Engulfs food by surrounding it with their

pseudopodspseudopods- amoebas, foraminiferansamoebas, foraminiferans

Animal-like Protists - continuedAnimal-like Protists - continued

3.3. CiliatesCiliates (Phylum Ciliaphora) (Phylum Ciliaphora)- Move by cilia (hair-like projections) Move by cilia (hair-like projections) - ParameciumParamecium – common genus – common genus

4.4. SporozoansSporozoans (Phylum Apicomplexa) (Phylum Apicomplexa)- Parasitic, reproduce using sporesParasitic, reproduce using spores- PlasmodiumPlasmodium – genus causes Malaria – genus causes Malaria- Malaria passed on by Malaria passed on by AnophelesAnopheles mosquitoes mosquitoes- Malaria kills millions of people annuallyMalaria kills millions of people annually

Questions 1-2, page 576Questions 1-2, page 5761.1. Name the three main groups within the kingdom Name the three main groups within the kingdom

Protista. What characteristics distinguish each group Protista. What characteristics distinguish each group from the other two?from the other two?

- Protozoa (animal-like) - heterotrophic consumersProtozoa (animal-like) - heterotrophic consumers- Algae (plant-like) - autotrophic producersAlgae (plant-like) - autotrophic producers- slime molds (fungal-like) - heterotrophic slime molds (fungal-like) - heterotrophic

decomposersdecomposers

2.2. Give two reasons why protists are difficult to classify.Give two reasons why protists are difficult to classify.

- Answers should include two of the following: Some Answers should include two of the following: Some protist phyla are very distantly related, and some are protist phyla are very distantly related, and some are more closely related to members of other kingdoms more closely related to members of other kingdoms than they are to other protists. The definition of protists than they are to other protists. The definition of protists is based on the absence of traits that characterize the is based on the absence of traits that characterize the other kingdoms.other kingdoms.

Questions 3 & 4, p576Questions 3 & 4, p5763.3. What observable traits might green algae and plants What observable traits might green algae and plants

share that support the molecular evidence that these share that support the molecular evidence that these two groups are closely related?two groups are closely related?

- Both are green, have chloroplasts, are eukaryotic, Both are green, have chloroplasts, are eukaryotic, and are (sometimes) multicellularand are (sometimes) multicellular

4.4. At one time, scientists grouped all single-celled At one time, scientists grouped all single-celled organisms together. What are the main differences organisms together. What are the main differences between single celled protists and bacteria or archaea?between single celled protists and bacteria or archaea?

- Protists are eukaryotic, meaning they are made up of Protists are eukaryotic, meaning they are made up of cells that have a nucleus and membrane-bound cells that have a nucleus and membrane-bound organelles; bacteria and archaea are prokaryotic, organelles; bacteria and archaea are prokaryotic, meaning their cells do not have a nucleus or organelles.meaning their cells do not have a nucleus or organelles.

Question 5, p 576Question 5, p 576

5.5. Organisms that get their food by ingesting Organisms that get their food by ingesting it called heterotrophs, while those that it called heterotrophs, while those that make their own food are called make their own food are called autotrophs. Categorize animal-like, plant-autotrophs. Categorize animal-like, plant-like, and fungus-like protists using these like, and fungus-like protists using these two terms.two terms.

- Animal-like protists and fungus-like are Animal-like protists and fungus-like are heterotrophs. Plant-like protists are heterotrophs. Plant-like protists are autotrophs. autotrophs.

Questions 1-2, p580Questions 1-2, p5801.1. Name and describe the three basic means of movement used by Name and describe the three basic means of movement used by

animal-like protists.animal-like protists.- flagella: tail-like extensions of cytoplasm that are used in a whip like flagella: tail-like extensions of cytoplasm that are used in a whip like

motion to propel the organism forwardmotion to propel the organism forward- Pseudopods: the plasma membrane and cytoplasm extend to form a Pseudopods: the plasma membrane and cytoplasm extend to form a

bulge that anchors to the surface and pulls the rest of the organism bulge that anchors to the surface and pulls the rest of the organism along; cilia: short hair like structures on the surface of the organism along; cilia: short hair like structures on the surface of the organism that wave.that wave.

2.2. Describe how the parasite Describe how the parasite Plasmodium Plasmodium causes disease in humans.causes disease in humans.- The bite of a mosquito carrying The bite of a mosquito carrying Plasmodium Plasmodium transmits sporozoites transmits sporozoites

into a human‘s bloodstream. The sporozoites enter the liver, where into a human‘s bloodstream. The sporozoites enter the liver, where they develop and then move to red blood cells. They reproduce they develop and then move to red blood cells. They reproduce asexually until the red blood cells burst open, releasing asexually until the red blood cells burst open, releasing Plasmodium Plasmodium cells that can cells that can then be ingested by mosquitoes that bite the infected then be ingested by mosquitoes that bite the infected host. Symptoms include severe fever, vomiting, and possibly liver and host. Symptoms include severe fever, vomiting, and possibly liver and kidney problems.kidney problems.

Questions 3-4, p 580Questions 3-4, p 5803.3. In what ways are cilia and flagella similar? In what ways are cilia and flagella similar?

How are they different?How are they different?

- Cilia and flagella are both used for movement Cilia and flagella are both used for movement in protists. Both are formed from the cell in protists. Both are formed from the cell membrane and are permanent structures. membrane and are permanent structures. However, cilia are shorter and more hair like However, cilia are shorter and more hair like and can be in rows or clusters that cover parts and can be in rows or clusters that cover parts of a cell or the entire cell. Flagella are longer, of a cell or the entire cell. Flagella are longer, and there are usually only one or two per cell.and there are usually only one or two per cell.

4.4. Why do amoebas form pseudopods only when Why do amoebas form pseudopods only when they need them?they need them?

- because pseudopod formation requires energybecause pseudopod formation requires energy

Question 5, p580Question 5, p580

5.5. The flagella of eukaryotes and The flagella of eukaryotes and prokaryotes serve the same function, but prokaryotes serve the same function, but they are structurally very different. What they are structurally very different. What does this suggest about the evolution of does this suggest about the evolution of flagella?flagella?

- The flagella of eukaryotes and The flagella of eukaryotes and prokaryotes arose separately and are an prokaryotes arose separately and are an example of convergent evolutionexample of convergent evolution

Plant-like Protists (Algae)Plant-like Protists (Algae)- Was classified in the plant kingdom in the past, Was classified in the plant kingdom in the past,

are not any more because they lack roots, stems, are not any more because they lack roots, stems, leaves or specialized tissuesleaves or specialized tissues

- Can be single-celled or multicellularCan be single-celled or multicellular- along with photosynthetic bacteria are sometimes along with photosynthetic bacteria are sometimes

called phytoplankton (photosynthesis)called phytoplankton (photosynthesis)- Provide about half of the earth’s oxygen supply!Provide about half of the earth’s oxygen supply!- Base of aquatic food chains as the producersBase of aquatic food chains as the producers- Most are autotrophic (make their own food by Most are autotrophic (make their own food by

photosynthesisphotosynthesis

Plant-like Protists – 6 phylaPlant-like Protists – 6 phyla1.1. EuglenoidsEuglenoids (phylum Euglenophyta) (phylum Euglenophyta)

- Swim by flagella, yet they photosynthesize!Swim by flagella, yet they photosynthesize!- Mostly freshwater species, some marineMostly freshwater species, some marine- Commonly green in colourCommonly green in colour- EuglenaEuglena- Most are autotrophic, some are heterotrophicMost are autotrophic, some are heterotrophic

2.2. DinoflagellatesDinoflagellates (phylum Dinoflagellata) (phylum Dinoflagellata)- Most species are marine (90%)Most species are marine (90%)- Have two flagellaHave two flagella- Some species produce toxins (cause “red tide”) – kill Some species produce toxins (cause “red tide”) – kill

large numbers of fish, can contaminate shellfish (can kill large numbers of fish, can contaminate shellfish (can kill people!)people!)

3.3. DiatomsDiatoms (phylum Bacillariophyta) (phylum Bacillariophyta)- Covered by delicate glass-like shellsCovered by delicate glass-like shells- Freshwater or marine species, unicellularFreshwater or marine species, unicellular- Release huge amounts of the earth’s atmospheric Release huge amounts of the earth’s atmospheric

oxygenoxygen- Diatomaceous earth – used in many things like tooth Diatomaceous earth – used in many things like tooth

paste, swimming pool filters, insulation materialspaste, swimming pool filters, insulation materials

4.4. Green Algae Green Algae (phylum Chlorophyta)(phylum Chlorophyta)- Most species are aquatic, some live on land in moist Most species are aquatic, some live on land in moist

environmentsenvironments- Some unicellular, some colonial, some multicellularSome unicellular, some colonial, some multicellular- Ancestor to land plantsAncestor to land plants

5.5. Brown AlgaeBrown Algae (phylum Phaeophyta) (phylum Phaeophyta)- Kelps that form underwater forestsKelps that form underwater forests- multicellularmulticellular- Mostly marine speciesMostly marine species

6.6. Red Algae Red Algae (phylum Rhodophyta)(phylum Rhodophyta)

- Mostly marine, some freshwaterMostly marine, some freshwater

- MulticellularMulticellular

- Carrageenan - thickening agent from red Carrageenan - thickening agent from red algae used dairy product like milkshakes algae used dairy product like milkshakes and ice creamand ice cream

- Agar – used in bacterial culture platesAgar – used in bacterial culture plates

Fungal-like ProtistsFungal-like Protists

1.1. Slime Molds (phylum Myxomycota / Slime Molds (phylum Myxomycota / Acrasiomycota)Acrasiomycota)

- eukaryotic, can move aroundeukaryotic, can move around

2.2. Water Molds (phylum Oomycota)Water Molds (phylum Oomycota)- Many are decomposers, some are parasites on Many are decomposers, some are parasites on

plants and fishplants and fish- One species caused the Irish potato famine – klled One species caused the Irish potato famine – klled

millions of people in Ireland “Great Potato Famine”millions of people in Ireland “Great Potato Famine”