Protista Flashcards
(137 cards)
Q: What are the main characteristics that define the phylum Sacramastigophora?
A: they are the largest Protozoa , Members of Sacramastigophora are protozoans with pseudopodia or flagella for movement, they are mostly unicellular, and reproduce mainly through asexual binary fission. They include both free-living and parasitic species.
Q: Describe the key structural features of organisms in the phylum Sacramastigophora.
A: They typically have a cellular body covered by a pellicle or test, one or multiple nuclei, flagella (usually one or two) for locomotion, and pseudopodia in some groups. The body may be elongated or spiral-shaped.
Q: What is the significance of the flagella in Sacramastigophora, especially in the class Phytomastigophora?
A: The flagella are used for locomotion; in Phytomastigophora, flagella assist in movement and phototaxis. They may also contain chloroplasts for photosynthesis.
Q: Explain the structure and function of the pellicle found in Sacramastigophora.
A: The pellicle is a tough, elastic or rigid outer layer that supports the cell membrane, maintains shape, and protects the cell during movement.
Q: How do organisms in the phylum Sacramastigophora reproduce?
A: Mainly through asexual binary fission, where a multinucleate parent divides into two daughter cells. Sexual reproduction may also occur in some species via conjugation or syngamy.
Q: What are chloroplasts’ role in Phytomastigophora, and name an example organism?
A: Chloroplasts enable photosynthesis, allowing these protists to produce their own food. An example is Euglena.
Q: [Image of Euglena showing flagellum, chloroplasts, nucleus, pellicle] - Label the structures and describe their functions.
A: (Labels: Flagellum for locomotion, Chloroplasts for photosynthesis, Nucleus for genetic control, Pellicle for shape and protection). Euglena can photosynthesize or ingest food depending on environmental conditions.
Q: How does Ceratium, a dinoflagellate, differ structurally from Euglena?
A: Ceratium has a complex cellulose cell covering called a lorica, two flagella (transverse and longitudinal) for movement, and typically has spines for protection, whereas Euglena has a simpler pellicle and a single flagellum.
Q: Describe the body shape and protective structure of Ceratium.
A: Ceratium has an elongated, armored body with two to five armoured spines and a thick lorica that encloses the cell, providing protection and buoyancy in aquatic environments.
Q: What is the function of the chlorophyll-containing chromatophores in Phytomastigophora?
A: They contain chlorophyll, which allows the organism to perform photosynthesis and produce energy from light.
Q: Name two examples of Phytomastigophora and describe their ecological roles.
A: Euglena (photosynthetic, freshwater; can be heterotrophic in darkness), Volvox (colonial algae); both contribute to aquatic ecosystems as primary producers.
Q: Explain the structure of Dinoflagellate body and how it moves.
A: The dinoflagellate body is enclosed in a cellulose lorica with two flagella—one transverse in a groove and one longitudinal—used for spinning and movement in water.
Q: How do flagella in Sacramastigophora differ from pseudopodia in Sarcodina?
A: Flagella are whip-like structures used primarily for movement in Sacramastigophora, while pseudopodia are temporary cytoplasmic projections used for movement and feeding in Sarcodina.
Q: [Diagram prompt] Draw and label the typical structures found in Euglena, including flagellum, chloroplasts, nucleus, and pellicle.
A: (User draws and labels).
Q: Summarize the diversity within Sacramastigophora in terms of their mode of nutrition and ecological roles.
A: They include autotrophic (photosynthetic Euglena), heterotrophic, parasitic, or mixotrophic forms. They play roles as primary producers or pathogens in ecosystems.
Q: What are the differences between free-living and parasitic members of Sacramastigophora?
A: Free-living species such as Euglena perform photosynthesis and feed on organic matter, while parasitic species like Trypanosoma invade host tissues, causing diseases.
Q: How is the structure of Trypanosoma adapted to its parasitic lifestyle?
A: Trypanosoma has a flexible body with a single flagellum, an undulating membrane aiding movement in blood and tissues, and specialized organelles to invade host cells.
Q: [Labelled diagram of Trypanosoma showing flagellum, undulating membrane, nucleus] - Identify and describe the functioning of each part.
A: The flagellum propels the parasite; the undulating membrane helps in movement; the nucleus controls cellular activities.
Q: What are the main characteristics that define the phylum Opalinata?
A: Opalinata are flat, parasitic protozoans with pellicle covering their bodies, covered by oblique rows of cilia for locomotion, with two or more isomorphic nuclei, and reproduce mainly by binary fission. They are found in the intestines of amphibians.
Q: Describe the body structure of Opalinata organisms.
A: They have a flattened, oval or elongated body covered with a pellicle, arranged in oblique rows of cilia for movement, and contain two or more isomorphic nuclei. They lack cytostome and contractile vacuoles.
Q: How do Opalinata reproduce?
A: They reproduce mainly through binary fission, asexual reproduction, with no known sexual process in most species.
Q: What habitats do Opalinata inhabit and what is their significance?
A: They inhabit the intestines of amphibians like frogs and toads, often as parasites, aiding in digestion of cellulose from the host’s diet.
