2.E Protozoa

X. MENGENAL LEBIH DEKAT ANGGOTA DUNIA MIKROBA

02. PENGGOLONGAN MIKROORGANISMEE. PROTOZOA

Protozoa are a Protozoa are a polyphyletic group polyphyletic group of organisms of organisms

1. PENDAHULUAN Phylogenetic Diagram 27 Tentative Phylogeny of theProtozoan-Like Eucaryotes Based on 18S rRNA SequenceComparisons.



Protozoa are unicellular, eucaryotic protists that are usually motile Protozoa are unicellular, eucaryotic protists that are usually motile Protozoology is the study of protozoaProtozoology is the study of protozoa

1. PENDAHULUAN



Some protozoa are anaerobic (e.g., Trichonympha lives in the gut of termites) Some protozoa are anaerobic (e.g., Trichonympha lives in the gut of termites)

1. PENDAHULUAN

Most anaerobic protozoa (such as Most anaerobic protozoa (such as Trichonympha, which lives in the gut of Trichonympha, which lives in the gut of termites; see figure 28.26) have no termites; see figure 28.26) have no mitochondria, no cytochromes, and an mitochondria, no cytochromes, and an incomplete tricarboxylic acid cycle.incomplete tricarboxylic acid cycle.

However, some do have small, However, some do have small, membrane-delimited organelles termed membrane-delimited organelles termed hydrogenosomes. These structures hydrogenosomes. These structures contain a unique electron transfer contain a unique electron transfer pathway in which hydrogenase transfers pathway in which hydrogenase transfers electrons to protons (which act as the electrons to protons (which act as the terminal electron acceptors), and terminal electron acceptors), and molecular hydrogen is formed.molecular hydrogen is formed.



Other protozoa have mitochondria with discoid Other protozoa have mitochondria with discoid cristae (trypanosomes), tubular mitochondrial cristae (trypanosomes), tubular mitochondrial cristae (ciliates, sporozoa), and lamellar cristae cristae (ciliates, sporozoa), and lamellar cristae (foraminiferans).(foraminiferans).

1. PENDAHULUAN

Structure of an apicomplexan

sporozoite.



Primarily in moist habitats (because they lack a cell wall), including freshwater Primarily in moist habitats (because they lack a cell wall), including freshwater (ponds, streams, lakes) and marine (oceans)(ponds, streams, lakes) and marine (oceans)

Some live in moist soil, beach sand, and decaying organic matterSome live in moist soil, beach sand, and decaying organic matter Most are free living, free-living, critical members of plankton drifting Most are free living, free-living, critical members of plankton drifting

organisms that form the basis of aquatic food chainsorganisms that form the basis of aquatic food chains Some are parasitic in plants and animalsSome are parasitic in plants and animals Very few are pathogensVery few are pathogens

2. DISTSRIBUSI



Serve as an important link in food chains and food webs (zooplankton) Serve as an important link in food chains and food webs (zooplankton) Food chain-series of organisms, each feeding on the preceding one Food chain-series of organisms, each feeding on the preceding one Food web-complex interlocking series of food chainsFood web-complex interlocking series of food chains

Important in the study of biochemistry and molecular biology because they Important in the study of biochemistry and molecular biology because they use the same metabolic pathways as multicellular eucaryotes use the same metabolic pathways as multicellular eucaryotes

Causative agents of some important diseases in humans and other animalsCausative agents of some important diseases in humans and other animals

3. NILAI PENTING



3. NILAI PENTING



Protozoa have some unique featuresProtozoa have some unique features

ECTOPLASMECTOPLASM is the gelatinous cytoplasm just inside the plasma membrane; it is the gelatinous cytoplasm just inside the plasma membrane; it provides some rigidity and shape provides some rigidity and shape

PELLICLEPELLICLE consists of the plasma membrane and the structures immediately consists of the plasma membrane and the structures immediately beneath it beneath it

ENDOPLASMENDOPLASM is the more fluid cytoplasm in the interior of the cell is the more fluid cytoplasm in the interior of the cell Some have one nucleus, some have two or more identical nuclei, and some have Some have one nucleus, some have two or more identical nuclei, and some have

two distinct types of nuclei two distinct types of nuclei The The MACRONUCLEUSMACRONUCLEUS is associated with trophic activities and regenerative processes is associated with trophic activities and regenerative processes The The MICRONUCLEUSMICRONUCLEUS controls reproductive activities by sequestering genetic material controls reproductive activities by sequestering genetic material

for exchange during reproductionfor exchange during reproduction

VACUOLESVACUOLES are usually present are usually present CONTRACTILE VACUOLESCONTRACTILE VACUOLES are osmoregulatory are osmoregulatory PHAGOCYTIC VACUOLESPHAGOCYTIC VACUOLES are sites of food digestion are sites of food digestion SECRETORY VACUOLESSECRETORY VACUOLES usually contain enzymes for specific functions, such as usually contain enzymes for specific functions, such as

excystationexcystation

4. MORFOLOGI



In holozoic nutrition, nutrients are acquired by PHAGOCYTOSIS; some ciliates In holozoic nutrition, nutrients are acquired by PHAGOCYTOSIS; some ciliates have a specialized structure, called a CYTOSOME, for phagocytosis have a specialized structure, called a CYTOSOME, for phagocytosis

In SAPROZOIC NUTRITION, nutrients are acquired by PINOCYTOSIS, In SAPROZOIC NUTRITION, nutrients are acquired by PINOCYTOSIS, DIFFUSION, or CARRIER-MEDIATED TRANSPORT (facilitated diffusion or DIFFUSION, or CARRIER-MEDIATED TRANSPORT (facilitated diffusion or active transport)active transport)

5. NUTRISI



ENCYSTATIONENCYSTATION is the development of a resting stage structure called a cyst is the development of a resting stage structure called a cyst The cyst is a dormant form that has a wall and greatly reduced metabolic activity The cyst is a dormant form that has a wall and greatly reduced metabolic activity Functions of cysts Functions of cysts

Protect against adverse changes in the environment Protect against adverse changes in the environment Function as sites for nuclear reorganization and cell division Function as sites for nuclear reorganization and cell division Serve as a means of transfer from one host to another for parasitic speciesServe as a means of transfer from one host to another for parasitic species

EXCYSTATIONEXCYSTATION is the escape of vegetative forms, called trophozoites, from the is the escape of vegetative forms, called trophozoites, from the cyst; it is usually triggered by a return to a favorable environment (e.g., such cyst; it is usually triggered by a return to a favorable environment (e.g., such as entry into a new host for parasitic species)as entry into a new host for parasitic species)

6. ENCYSTMENT AND EXCYSTMENT



A few protozoa are nonmotile A few protozoa are nonmotile Most use one of three major types of locomotory organelles Most use one of three major types of locomotory organelles

Pseudopodia-cytoplasmic extensions Pseudopodia-cytoplasmic extensions CILIACILIA-filamentous extensions (short) -filamentous extensions (short) FLAGELLAFLAGELLA-filamentous extensions (long)-filamentous extensions (long)

7. ORGANEL PERGERAKAN

flagellum.swf



The most common method of ASEXUAL reproduction is: The most common method of ASEXUAL reproduction is: BINARY FISSION, which involves mitosis followed by cytokinesis BINARY FISSION, which involves mitosis followed by cytokinesis

The most common type of SEXUAL reproduction is:The most common type of SEXUAL reproduction is: conjugation, an exchange of gametic nuclei between paired protozoa of conjugation, an exchange of gametic nuclei between paired protozoa of

complementary mating typescomplementary mating types

8. REPRODUKSI



8. REPRODUKSI

Figure 27.2 Conjugation in Paramecium caudatum, Schematic Drawing. Follow the arrows. After theconjugants separate, only one of the exconjugants is followed; however, a total of eight new protozoa result from the conjugation.



The most accepted scheme classifies protozoa as a subkingdom The most accepted scheme classifies protozoa as a subkingdom of protists, containing of protists, containing SEVEN PHYLASEVEN PHYLA; ;

Classification is based primarily on: Classification is based primarily on: types of nuclei, types of nuclei, mode of reproduction, and mode of reproduction, and mechanism of locomotionmechanism of locomotion

Recently, other schemes have been suggested Recently, other schemes have been suggested CAVALIER-SMITH has proposed elevating the protozoa to CAVALIER-SMITH has proposed elevating the protozoa to

the status of a kingdom with 18 phyla the status of a kingdom with 18 phyla Molecular classification schemes suggest that the protozoa Molecular classification schemes suggest that the protozoa

do not exist as an evolutionary taxon, but rather that the do not exist as an evolutionary taxon, but rather that the protozoa are polyphyleticprotozoa are polyphyletic

9. PENGGOLONGAN PROTOZOA



1)1) SARCOMASTIGOPHORASARCOMASTIGOPHORA

2)2) LABYRINTHOMORPHALABYRINTHOMORPHA

3)3) APICOMPLEXAAPICOMPLEXA

4)4) MICROSPORAMICROSPORA

5)5) ACETOSPORAACETOSPORA

6)6) MYXOZOAMYXOZOA

7)7) CILIOPHORACILIOPHORA


PHYLUM:



1) SARCOMASTIGOPHORA1) SARCOMASTIGOPHORA9. PENGGOLONGAN PROTOZOA

This phylum includes protists with:

a single type of nucleus and

flagella or pseudopodia;

they reproduce asexually and

sexually

This phylum includes:

Subphylum MASTIGOPHORA Subphylum SARCODINA



1) SARCOMASTIGOPHORA 1) SARCOMASTIGOPHORA (lanjutan)(lanjutan)


Subphylum MASTIGOPHORA

contains both phytoflagellates (chloroplast-bearing

flagellates) and zooflagellates;

ZOOFLAGELLATES have the following characteristics:

Do not have chlorophyll; are holozoic or saprozoic

Asexual reproduction occurs by LONGITUDINAL BINARY FISSION;

sexual reproduction is known for a few species, and ENCYSTMENT

is common





One group, the kinetoplastids, has mitochondrial DNA in a special region called the KINETOPLAST

Some are free living; some are ENDOSYMBIOTIC (e.g., Trichonympha species in the intestines of termites)





Many are important HUMAN PARASITES e.g.,

Trichomonas vaginalis,

Giardia lamblia

Trypanosoma brucei




contains amoeboid organisms Found in aquatic and terrestrial habitats, where

they take up nutrients by PHAGOCYTOSIS and PINOCYTOSIS

Reproduction is usually by simple ASEXUAL BINARY FISSION; some form CYSTS

Some have a loose-fitting shell called a TEST (e.g., foraminiferans and radiolarians, which are primarily marine amoebae; a few occur in fresh or brackish water)

Some are ENDOSYMBIONTS and can be either commensals or parasites; some are free-living, disease-causing amoebae


Subphylum SARCODINA