(Animal Euglena, 2000)
The process of Amoeba and Paramecium of obtaining their food is quite similar, but they use different movements to get their food. Amoeba has pseudopodium that helps it to catch its prey, and paramecium has cilium that helps it to move. (Maronich, M)
Aim:
To observe tiny organisms that belongs to the Protist Kingdom, and to state the differences between the five.
Apparatus:
Amoeba, paramecium, stentor, chlamydomonas, and euglena
Microscope
Cavity slide
Cover slip
Eye dropper
Glycerine
Method:
- Get into pairs
- Look at the bottle carefully, to spot the organisms with the naked. If the organisms are visible with the naked then the organism is macroscopic and if not then they are microscopic.
- Set up the microscope.
- Get the eyedropper and place it into the bottle to get some sample of the organism. Place it onto the cavity slide and over it put the cover slip to secure it. Place the cavity slide under the microscope.
- Focus into the organism and if the is moving then explain its movement in the table. Observe them and record the results by filling in the table.
- Organisms that move fast uncover the cover slip and add a drop of glycerine to make the movement slower, and then place the cover slip back on.
- Observe each organism by repeating the same procedures above.
- When looking at euglena, draw a diagram and label it into micrometers, if euglena is moving a lot then place a drop of glycerine to make the movement slower.
- For each of the organism fill in the table, recording all the results.
- Pack up the equipment.
Results:
Drawing of euglena:
Magnification of euglena:
Discussion:
How do Amoeba and paramecium obtain their food?
Paramecium obtains its food by firstly using their cilia to sweep food, The food then leads into a funnel-like structure called the gullet. Paramecium’s food vacuoles surround the incoming food which pinches off into the cytoplasm. Food is then digested and the nutrients are circulated. After the work of the food vacuoles is finished, it joins with the area of the pellicles called the anal pore. The anal pores empty waste materials into the water and if the paramecium is then disturbed it may release sharp spines called trichochysts.
Amoebas obtain their food by using their pseudopods. If the amoeba wants food, it expands a thick, round pseudopod from part of its cell, and the rest of the cells flow into the pseudopod to surround the food. A bubble-like structure is formed that contains the food and the food vacuole. The food that has been digested can be then used as energy or growth. The waste products are then removed when the food vacuole joins with the cell membrane.
Which of the protozoans make its own food by photosynthesis? Provide reasons for your choice.
Protozoans like euglena are likely to make its own food by photosynthesis as they are all plant-like protists. Euglena has a chloroplast, which easily facilitates photosynthesis. There are others such as stentor and chlamydomonas. The algae, chlamydomonas reinhardtii, also has chloroplasts.
How do substances like oxygen and carbon dioxide move into and out of each protozoan? What features of each organism enable them to use this method?
Protozoans breathe in and out by a process called diffusion. This happens when oxygen enters the body and carbon dioxide leaves the body. Diffusion is a movement of molecules from regions of high concentration to low concentration, until they are even on both sides. Diffusion is achieved in cells by oxygen, and then the oxygen oxidizes food molecules, this produces energy
Respiration is accomplished by the diffusion of dissolved gases through the cell membrane. Oxygen diffuses into the cell, where it oxidizes food molecules, producing energy and the organic molecules used for the building and maintenance of the cell. Carbon dioxide and water, the waste products of this oxidation, diffuse out of the cell.
Which of the protozoans viewed appears to have an eyespot? What might it use this for?
The protozoan that appears to have an eyespot is euglena. Euglena has a red eye spot that detects light to help get its food.
The eyespot directs euglena to a light supply enough for photosynthesis to occur; this process is the same as a plant making its food. If there is any absence of light euglena absorbs dissolved nutrients from the surrounding environment.
Which classes do the protozoans belong to?
The classes of the protozoans are Class Flagellata, Class Sarcodina, Class Sporozoa, and Class Ciliata.
Flagellates have a whip like tail called flagella and most of these live independently. There are some Flagellata that live in other organisms and they can cause disease.
Sarcodina look like small stacks of cloudy gelatine and also move by pushing their parts out of their cell membrane. The fluids in Sarcodina cells flow in the direction they move.
Sporozoa also live in other organism and most of sporozoa don’t have a structure to move about. The transportation of these organisms depends on their host and these organisms can cause malaria by entering a human’s bloodstream.
Ciliata cells are covered by hair-like structures called cilia and cilium moves the organism by creating waves and then by pushing the organisms along. Cilium also helps the food sweep in the organism’s mouth-like structure.
What are the plant like and animal like characteristics of euglena?
Euglena uses its plant-like features to produce food using photosynthesis. The reason euglenas are green is because they eat green algae. The algae is then stored which is then used to make their own food, the green parts that are inside the body of the euglena are called chloroplasts. Euglena is a one celled organism, and these cells are very small to be seen by the naked eye.
Like animal cells, euglena has a long whip like flagellum used for locomotion. The body is typically elongated and somewhat spindle-shaped. It is enclose by a flexible, striated pellicle made chiefly of protein. The front end of the body forms a flask-shaped cavity, or reservoir. Extending from the reservoir is the flagellum. During active locomotion it is swung backward, and waves pass rapidly from its base to its tip. When an individual is in contact with a surface, peristaltic waves pass along the elastic pellicle resulting in a limited form of locomotion called euglenoid movement.
What problems (if any) were encountered? How could these be fixed?
Some of the protists had died by the time the amoeba and chlamydomonas could be viewed. This could have been fixed if people avoided squeezing them, and if chlaydomonas were sent alive to the experiment. Euglena had also died but the teacher allowed use of new sample.
How could this prac be improved?
This practical could be improved if we had prior knowledge of protists and the practical. If the some of the protists were alive, movement could have been detected.
Conclusion:
The aim of the experiment was achieved except one organism didn’t move, and hence no observations other than appearance could be made.
The tiny little organisms could be easily viewed where organisms had variety of shapes and colours. All were different to each other, even though they all belonged to the same kingdom.
Bibliography:
BOOKS
Wilkinson, J. 1987, Senior Biology, Macmillan, Australia (book)
INTERNET
Maronich, M. Kingdom Protista (Online) Available:
(Accessed on 28 May 2004)
(no other information)
ENCYCLOPAEDIA
The World Book Encyclopaedia 1992, vol 1 pp. 402-442, World Book, Inc, Chicago.
Cellular Structure and Function, Columbia Encyclopaedia, Sixth Edition. 2004 (Online) Available: (Accessed on 28 May 2004)
SAMPLE DESCRIPTIVE LAB REPORT. (Online) Available:
(Accessed on 28 May 2004)
Animal Euglena, Hutchinson Encyclopaedia. 2000. (Online) Available: (Accessed on 28 May 2004)
JOURNAL
Spengel, J. W, 2003, Protistologica in 1964 European Journal of Protistology
2003: Volume 39 (journal)
NEWSPAPER:
Blaine P. Friedlander Jr. 2002, Tiny plant poised to yield big payoffs in environment and energy as Boyce Thompson Institute reveals key genome sequence, Boyce Thomas Institute for Plant