Intro to Protozoan Notes

Kingdom: Protista

UnicellularEukaryoticAutotrophic w/ cell walls - AlgaeHeterotrophic w/out cell walls - Protozoans

Protozoans are the ancestors of the animal kingdom. We’ll discuss the evidence for that when we study the most primitive animals.

• Many are symbiotic with other organisms that are important to us (ex. Termites & Campanula).

• Many are symbiotic with other organisms that are important to us (ex. Termites).

• Disease vectors – organisms that transmits a disease.

• Many are symbiotic with other organisms that are important to us (ex. Termites).

• Disease vectors – organisms that transmits a disease.

• Many are parasitic upon humans.

Protozoan Taxonomy

The protozoans, like all organisms, are classified into more specific groups based on….

Protozoan Taxonomy

The protozoans, like all organisms, are classified into more specific groups. Protozoan taxonomy (classification) is based on….

• their mode of locomotion

Protozoan Taxonomy

The protozoans, like all organisms, are classified into more specific groups. Protozoan taxonomy (classification) is based on….

• their mode of locomotion

• the number and type of nuclei they have

Locomotion among protozoans

• Flagella – long, whip-like; usually one or two



• Cilia – short, bristle-like; hundreds to thousands



• Cilia – short, bristle-like; hundreds to thousands

• Pseudopodia – pseudo = false; pod = foot

an extension of the cell membrane into which the cytoplasm flows creating a directional movement.

Kingdom: Protista Phylum: Sarcomastigophora

(sarco = meat; mastix = a whip; and

phora (Greek) to bear.

Kingdom: Protista Phylum: Sarcomastigophora

(sarco = meat; mastix = a whip; and

phora (Greek) to bear.

sarco – because they are hunters (meat eaters)mastix – refers to the flagellum that some have phora – they may bear a whip (the flagellum)

Kingdom: Protista Phylum: Sarcomastigophora Subphylum: Sarcodina (common name is amoeba (plural amoebae) Note the common name isn’t capitalized.

CytNuc

Cont Pseud

Fvac

Draw and label this picture.

Kingdom: Protista Phylum: Sarcomastigophora Subphylum: Sarcodina (amoebas)

CytNuc

Cont Pseud

Fvac

Kingdom: Protista Phylum: Sarcomastigophora Subphylum: Sarcodina (amoebas)

CytNuc

Cont PseudCyt – cytoplasm

Cont – contractile vacuole

Nuc – nucleus

Pseud – pseudopodium

Fvac – food vacuole

Fvac

Amoebae have one kind of nucleus and move by flowing into their pseudopodia.

video clip….

https://www.youtube.com/watch?v=1FEMaadwVCQ

https://www.youtube.com/watch?v=1FEMaadwVCQ

They capture their food by surrounding it with pseudopodia, which then create a food vacuole.

https://www.youtube.com/watch?v=pvOz4V699gk





Process is called phagocytosis.





Process is called phagocytosis.

Enzymes from the cell’s lysosomes digest the food (bacteria, unicellular algae, and smaller protozoans)



After food is digested and the nutrients are absorbed into the cytoplasm, the vacuole (now called a waste vacuole) moves to the cell membrane, opens up, and squirts the wastes into the environment.

After food is digested and the nutrients are absorbed into the cytoplasm, the vacuole (now called a waste vacuole) moves to the cell membrane, opens up, and squirts the wastes inot the environment.

This is called reverse phagocytosis.

Ameoba reproduction is called binary fission (mitosis).


• DNA replicates and divides into two nuclei


• DNA replicates and divides into two nuclei

• Cell membrane pinches in and divides the ameoba into two amoebae.

Binary fission involves only one parent and the resulting new Amoebae have the same DNA.


Reproduction involving one parent and no exchange of DNA is called __________ reproduction.


Reproduction involving one parent and no exchange of DNA is called asexual reproduction.


Reproduction involving one parent and no exchange of DNA is called asexual reproduction.

This means that change (evolution) in amoebae is slow and can only result from mutations.

Water vacuoles collect excess water from inside the cell and move to the cell membrane where they open up and release it into the environment.

Water vacuoles collect excess water from inside the cell and move to the cell membrane where they open up and release it into the environment.

This process is called pinocytosis.

You will be responsible for knowing two diseases caused by to species of amoebae.

Amoebic Dysentery is a disease caused by an amoeba named Amoeba proteus.


One gets dysentery by drinking contaminated water (has A. proteus living in it).


One gets dysentery by drinking contaminated water (has A. proteus living in it).

Symptoms: extreme abdominal cramps, diarrhea resulting in severe dehydration, for small children dehydration can lead to death.

In September 2013, health officials in Louisiana investigated reports of people showing symptoms of a serious parasitic amoeba species.

New on Sept. 23

Phylum: Sarcomastigophora Subphylum: Mastigorphora Common Name: flagellates

The flagellates are protozoans that have one nucleus and move by means of one or more flagella.

monoflagellate biflagellatepolyfllagellate

Choanoflagellates are flagellates whose flagellum is surrounded by a collar.

Choana = Latin for collar

The flagellum beats to create a current that draws their prey (bacteria and smaller protozoans) to the collar.

The flagellum beats to create a current that draws their prey (bacteria and smaller protozoans) to the collar. Then pseudopodia pull the food into the cell.

Euglena is an excellent example of a phytoflagellate.


Phyto = plant


Phyto = plant

Euglena has chloroplasts and is capable of photosynthesis.


Phyto = plant

Euglena has chloroplasts and is capable of photosynthesis.

If food (bacteria & smaller protozoans) is available it is heterotrophic.

If food is not available, it has a eyespot (red in color) that is photosensitive.

If food is not available, it has a eyespot (red in color) that is photosensitive.

The eyespot guides it to light and it becomes autotrophic.

A flagellate that is only heterotrophic (like animals) is referred to as a zooflagellate.

A flagellate that is only heterotrophic (like animals) is referred to as a zooflagellate.

Trypanosoma invades the circulatory system of mammals and causes the disease known as African Sleeping Sickness.

Kingdom: Protista Phylum: Ciliophora Common name: ciliates


Ciliates are characterized by….



• two kinds of nuclei



• two kinds of nuclei • cilia for locomotion


Paramecium

http://www.youtube.com/watch?v=a4aZE5FQ284

Paramecium feeding….Note the oral groove, beating cilia, and the forming food vacuoles.



Stentor is a funnel-shaped protozoan.http://www.youtube.com/watch?v=rqD3m9hHhlo

http://www.youtube.com/watch?v=rqD3m9hHhlo

Vorticella is a stalked ciliate. The stalk coils and springs to stir the water and any smaller protozoans or bacteria in it so the Vorticella can feed on them.http://www.youtube.com/watch?v=YHb2JaujIPohttp://www.youtube.com/watch?v=mjOsc1F4exM

http://www.youtube.com/watch?v=YHb2JaujIPo


http://www.youtube.com/watch?v=mjOsc1F4exM

Vorticella is a stalked ciliate. The stalk coils and springs to stir the water and any smaller protozoans or bacteria in it so the Vorticella can feed on them.http://www.youtube.com/watch?v=YHb2JaujIPohttp://www.youtube.com/watch?v=mjOsc1F4exM



http://www.youtube.com/watch?v=mjOsc1F4exM

Ciliates reproduce asexually by binary fission (mitosis).

They reproduce sexually by conjugation.

During conjugation two ciliates join by their oral groove, and exchange a portion of the DNA from their macronucleus.

Because there are two parent cells and an exchange of DNA it is considered sexual reproduction (as opposed to asexual reproduction which involves one parent and no exchange of DNA).

Because there are two parent cells and an exchange of DNA it is considered sexual reproduction (as opposed to asexual reproduction which involves one parent and no exchange of DNA).

This mixing of genes leads to genetic diversity for the species and genetic diversity is the “raw material” for evolution.

Education

Intro to Protozoan Notes