Experiment 3

Experiment 3Phagocytosis in Tetrahymena sp. Group No. 3 Del Munda, Aristeo RenoirDel Villar, Maja RaelDomingo, Jerald JosephDraheim, KristellaEstrella, Brian Nicole

INTRODUCTIONEndocytosis The process by which cells absorb molecules (such as proteins) by engulfing them.

Types of Endocytosis : Phagocytosis and Pinocytosis.

PinocytosisThe process by which a cell takes in extracellular fluid by the invagination of the cell membrane.

A pocket then forms and pinches off to form a vesicle, which subsequently ruptures, releasing its contents into the cytosol.

It is nonspecific in the substances that it transports. PhagocytosisThe cellular process of engulfing solid particles by the cell membrane to form an internal phagosome by phagocytes and protists.

Engulfs whole particles, which are later broken down by enzymes and absorbed into the cells.

Involved in the acquisition of nutrients for some cells, and, in the immune system, it is a major mechanism used to remove pathogens and cell debris.

Tetrahymena sp. A free-living unicellular eukaryote.

A ciliate considered to be the most highly developed protozoan, because it possesses specialized organelles that perform each of the cell functions.

Commonly found in freshwater and even hot springs.

Possess rapid adaptation machineries to regulate biological processes including cell division, conjugation and cell death against intracellular and extracellular stresses.

Why use Tetrahymena sp. in observing Phagocytosis? They are easily obtained, cultured and manipulated.Phagocytosis can be observed under the microscope.Food vacuoles can be readily observed.

ObjectivesTo observe the phagocytosis process of Tetrahymena sp.

The experiment aims to observe the scrapings of graphite by Tetrahymena sp.

MaterialsTetrahymena cell suspension

Chlorella sp. culture

Microscope

Slides and cover slips

Micropippetors and tips

Graphite shavingsMethodsOn a slide, a drop of Tetrahymena sp. was put. Then, a cover slip was put on the slide. On the microscope, the slide with the Tetrahymena sp. was observed. The graphite from the lead of the pencil was scraped and was allowed to fall on the drop of the Tetrahymena sp. culture. A cover slip was placed above and the slide was observed under the microscope.

Group 1Cell no.Tetrahymena + graphite12345averageCell no.Tetrahymena + graphite12345averageGroup 2Cell no.Tetrahymena + graphite12345averageGroup 3Group 4Cell no.Tetrahymena + graphite12345averageGroup 4Cell no.Tetrahymena + graphite12345average

Group 5Cell no.Tetrahymena + graphite12345averageGroup 6Cell no.Tetrahymena + graphite12345averageGroup 7

Cell no.Tetrahymena + graphite12345average

Group 8Cell no.Tetrahymena + graphite12345AverageGroup 9Cell no.Tetrahymena + graphite12345averageGroup 9Cell no.Tetrahymena + graphite12345average

Tetrahymena + graphite Average123456789Class averageVideosResult and DiscussionIn unstained Tetrahymena sp., the most conspicuous structures are the food vacuoles.

When a hungry Tetrahymena sp. encounters food, they use their cilia to sweep into the cells buccal cavity.

Food vacuole number and formation depends on how much food eaten by the Tetrahymena.

Pathway of EndocytosisMovement of food to the buccal cavity is accomplished by cilia.

Food Vacuole Formation

Pinocytic vacuoles enters the food vacuole, takes the excess water and then leaves the food vacuole.

Lysosomes transport enzymes to the food vacuoles so food particles undergo digestion.

Once the nutrients has been absorbed, waste exits the vacuole.

Tetrahymena sp. and GraphiteGraphiteAn allotrope of carbonIt is used inpencilsGraphiteis a minimally-toxiccarbon based substance. Pencils do not contain any lead metal.Graphiteis a mineral composed exclusively of the element carbon.Graphitehas the samechemical compositionas Diamond, which is also pure carbon, but themolecularstructure ofGraphiteand Diamond is entirely different.

Food formation was low in number It inhibits ciliary action which also inhibits feeding and the rate of food vacuole formation.

Source: http://resourcescommittee.house.gov/subcommittees/emr/usgsweb/photogallery/

http://facweb.bhc.edu/academics/science/harwoodr/geol101/study/minerals.htmConclusionBased on the experiment conducted the average food vacuole formed in Tetrahymena sp. is higher when fed in Chlorella sp. than in graphite. Because Chlorella sp. is complete protein source and also packed with calories, fat, and vitamins.