Eukaryotes the Eukaryotic Cell
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Protists/Fungi Station Lab Information
Protists/Fungi Station Lab Information 1 Protists Information Seat #1 Background: Perhaps the most strikingly diverse group of organisms on Earth is that of the Protists, Found almost anywhere there is water – from puddles to sediments. Protists rely on water. Some are marine (salt water), some are freshwater, some are terrestrial (land dwellers) in moist soil and some are parasites which live in the tissues of others. The Protist kingdom is made up of a wide variety of eukaryotic cells. All protist cells have nuclei and other characteristics eukaryotic features. Some protists have more than one nucleus and are called “multinucleated”. Cellular Organization: Protists show a variety in cellular organization: single celled (unicellular), groups of single cells living together in a close and permanent association (colonies or filaments) or many cells = multicellular organization (ex. Seaweed). 1 Protists Information Seat #2 Obtaining food: There is a variety in how protists get their food. Like plants, many protists are autotrophs, meaning they make their own food through photosynthesis and store it as starch. It is estimated that green protist cells chemically capture and process over a billion tons of carbon in the Earth’s oceans and freshwater ponds every year. Photosynthetic or “green” protists have a multitude of chloroplasts (membrane-enclosed bags) which contain the photosynthetic green pigment called chlorophyll. Many of these organisms’ cell walls are similar to that of plant cells and are made of cellulose. Others are “heterotrophs”. Like animals, they eat other organisms or, like fungi, receiving their nourishment from absorbing nutrient molecules from their surroundings or digest living things. -
Cell Structure and Function Answered Review SP 08.Pdf
Answered Review Questions Cell Structure and Function Cell Location-Structure Function Prokaryote/ Structure Eukaryote Cell Forms outer boundary of Semi-permeable (restricts the Both membrane cell; access of certain compounds (Plasma and ions) membrane) Forms membrane-bound organelles Aids in maintaining the complex internal organization of a cell Cytoplasm Everything between the Site of most chemical reactions Both nuclear envelope (nucleoid of life region in prokaryotes) and the cell boundary Cytosol The semi-fluid portion of the Both cytoplasm Nucleus 10% of the volume of the cell Mission control—manages Eukaryotes protein synthesis only Nucleolus Small dense spheres within Genes for ribosomal RNA Eukaryotes the nucleus (often 2-3 (building block of ribosomes) only visible)—tightly coiled regions of the DNA Nuclear Porous double-membrane Protects the DNA Eukaryotes envelope organelle; only mRNA exits the nucleus Forms outer boundary of through pores after nucleus transcription Bound Small dense granules (each Site of protein synthesis Eukaryotes ribosomes has a large and a small only subunit) made of proteins Ribosomes build proteins and rRNA; Attached to endoplasmic reticulum; Can become free; Part of the endomembrane system Free Small dense granules (each Site of protein synthesis Both ribosomes has a large and a small subunit) made of proteins Ribosomes build proteins and rRNA; Suspended in cytosol; Can become bound Rough Network of membranous Modify proteins Eukaryotes endoplasmic tubes dotted with bound only reticulum ribosomes; Many proteins are modified here by cleaving the Loosely surrounds the polypeptide, forming quaternary nucleus; structures, removing amino acids or adding non-protein Part of the endomembrane substances (e.g. -
Cysteine Proteases in Protozoan Parasites
REVIEW Cysteine proteases in protozoan parasites Jair L. Siqueira-Neto1*, Anjan Debnath1, Laura-Isobel McCall1¤, Jean A. Bernatchez1, Momar Ndao2,3, Sharon L. Reed4, Philip J. Rosenthal5 1 Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, United States of America, 2 National Reference Centre for Parasitology, The Research Institute of the McGill University Health Center, Montreal, Canada, 3 Program in Infectious Diseases and Immunity in Global Health, The Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada, 4 Departments of Pathology and Medicine, University of California San Diego School of Medicine, La Jolla, California, United States of America, 5 Department of Medicine, University of California, San Francisco, San Francisco, California, a1111111111 United States of America a1111111111 a1111111111 ¤ Current address: Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma, a1111111111 United States of America a1111111111 * [email protected] Abstract OPEN ACCESS Cysteine proteases (CPs) play key roles in the pathogenesis of protozoan parasites, includ- Citation: Siqueira-Neto JL, Debnath A, McCall L-I, ing cell/tissue penetration, hydrolysis of host or parasite proteins, autophagy, and evasion Bernatchez JA, Ndao M, Reed SL, et al. (2018) or modulation of the host immune response, making them attractive chemotherapeutic and Cysteine proteases in protozoan parasites. PLoS vaccine targets. This review highlights current knowledge on clan CA cysteine proteases, Negl Trop Dis 12(8): e0006512. https://doi.org/ 10.1371/journal.pntd.0006512 the best-characterized group of cysteine proteases, from 7 protozoan organisms causing human diseases with significant impact: Entamoeba histolytica, Leishmania species (sp.), Editor: Photini Sinnis, Johns Hopkins Bloomberg School of Public Health, UNITED STATES Trypanosoma brucei, T. -
Intracellular Symbiosis of Algae with Possible Involvement Of
www.nature.com/scientificreports OPEN Intracellular symbiosis of algae with possible involvement of mitochondrial dynamics Received: 19 October 2016 Chihong Song1,3, Kazuyoshi Murata2 & Toshinobu Suzaki1 Accepted: 27 March 2017 Algal endosymbiosis is widely present among eukaryotes including many protists and metazoans. Published: xx xx xxxx However, the mechanisms involved in their interactions between host and symbiont remain unclear. Here, we used electron microscopy and three-dimensional reconstruction analyses to examine the ultrastructural interactions between the symbiotic zoochlorella and the organelles in the host Paramecium bursaria, which is a model system of endosymbiosis. Although in chemically fixed samples the symbiotic algae show no direct structural interactions with the host organelles and the perialgal vacuole membrane (PVM), in cryofixedP . bursaria samples the intimate connections were identified between the host mitochondria and the symbiotic algae via the PVM. The PVM was closely apposed to the cell wall of the symbiotic algae and in some places it showed direct contacts to the host mitochondrial membrane and the cell wall of the symbiotic algae. Further, the PVM-associated mitochondria formed a mitochondrial network and were also connected to host ER. Our observations propose a new endosymbiotic systems between the host eukaryotes and the symbionts where the benefiting symbiosis is performed through intimate interactions and an active structural modification in the host organelles. A number of algae live in cells of protists and invertebrates such as Porifera and Cnidaria1, 2. A recent study also reported that algae invade and live in symbiosis with embryonic salamander tissues and cells3. Algal symbionts obtain nitrogen and carbon dioxide from the host cells and provide the host with photosynthetic products1–6. -
Protists – Amoeba Anatomy
Name______________________________ Biology II --- February 2012 Protists – Amoeba Anatomy Amoeba The amoeba is a protozoan that belongs to the Kingdom Protista. The name ameba comes from the Greek word "amoibe", which means change. Amoeba is also spelled ameba. Protists are microscopic unicellular organisms that don't fit into the other kingdoms. Some protists are considered plant-like while others are considered animal-like. The animal-like protists are known as protozoans. The amoeba is considered an animal-like protist because it moves and consumes its food. Protists are classified by how they move, some have cilia or flagella, but the amoeba has an unusual way of creeping along by stretching its cytoplasm into fingerlike extensions called pseudopodia. The word "pseudopodia" means "false foot". Label the pseudopodia. When looking at amoeba under a microscope, an observer will note that no amoebas looks the same as any other, the cell membrane is very flexible and allows for the amoeba to change shape. Color and label the cell membrane red. Amoebas live in ponds or puddles, and can even live inside people. There are two types of cytoplasm in the amoeba, the darker cytoplasm toward the interior of the protozoan is called endoplasm, and the clearer cytoplasm that is found near the cell membrane is called ectoplasm. Color and label the ectoplasm light blue and the endoplasm pink. By pushing the endoplasm toward the cell membrane, the amoeba causes its body to extend and creep along. The amoeba also uses this method to consume its food. The pseudopodia extend out and wrap around a food particle in a process call phagocytosis. -
Nutrient Uptake in Tetrahymena Pyriformis
NUTRIENT UPTAKE IN TETRAHYMENA PYRIFORMIS by LEIF RASMUSSEN The Biological Institute of the Carlsberg Foundation 16 Tagensvej, DK-2200 Copenhagen N, Denmark Key words:food vacuoles;pinocytic vesicles;plasma membrane Several morphological structures have been implicated in nutrient uptake in the ciliate protozoon, Tetrahymena pyriformis: food vacuoles, various types of vesicles and the plasma membrane. It is the object of this report to dis- cuss the roles of these organelles in food uptake. Measurements of multiplication rates under conditions where food vacuole formation could be controlled experimentally suggested that the food vacuoles (about 5 rtm in diameter) were essential for rapid cell multiplication in various standard growth media. If, however, con- centrations of certain specific nutrients (different for different strains of T. pyriformis) were high, then the cells could multiply rapidly even when food vacuoles were absent. Furthermore, multiplication rates of cells supplied with particulate or dissolved egg albumin as the amino acid source, suggested that the food vacuoles took up particulate egg albumin well, but dissolved egg albumin poorly. The role in food uptake of vesicles with a diameter of less than 1 vm remains largely unknown. Our present knowledge of them is not yet sufficiently detailed to permit estimations of the rates with which they are formed or of their total number per cell. The plasma membrane has carrier-mediated uptake sites for a number of nutrients such as amino acids and nucleosides. It is likely that this type of uptake mechanism plays a quantitatively important role in T. pyriformis whenever such compounds are present in the extracellular fluid. -
Neutral Red Granules and Food Vacuoles in Tetrahymena Pyriformis Robert Alan Grassmick Iowa State University
Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1971 Neutral red granules and food vacuoles in Tetrahymena pyriformis Robert Alan Grassmick Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Zoology Commons Recommended Citation Grassmick, Robert Alan, "Neutral red granules and food vacuoles in Tetrahymena pyriformis " (1971). Retrospective Theses and Dissertations. 4456. https://lib.dr.iastate.edu/rtd/4456 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. 72-5204 GRASSMICK, Robert Alan, 1936- NEUTRAL RED GRANULES AND FOOD VACUOLES IN TETRAHYMENA PYRIFORMIS. Iowa State University, Ph.D., 1971 Zoology ; University Microfilms, A XEROX Company, Ann Arbor, Michigan THIS DISSERTATION HAS BEEN MICROFILMED EXACTLY AS RECEIVED Neutral red granules and food vacuoles in Tetrahymena "pyriformis by Robert Alan Grassmick A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment of The Requirements for the Degree of DOCTOR OF PHILOSOPHY Major Subject: Zoology (Protozoology) Approved: Signature was redacted for privacy. Signature was redacted for privacy. Signature was redacted for privacy. For the Graduate College -
Eukaryotic Cells | Principles of Biology from Nature Education
contents Principles of Biology 14 Eukaryotic Cells Eukaryotic cells contain membrane-enclosed organelles that play a pivotal role in their structure and function. A pseudo-colored freeze-fracture transmission electron micrograph (TEM) of the nucleus of a pig kidney cell. Pores (yellow) in the nuclear membrane regulate the movement of molecules into and out of the nucleus of eukaryotic cells. Magnification = 25,000x Biophoto Associates/Science Source. Topics Covered in this Module Components of a Eukaryotic Cell Diverse Form and Function of Eukaryotic Cells Major Objectives of this Module Identify cellular structures on a micrograph or diagram and name their functions. Relate the forms of different cell structures to their functions. Compare and contrast the structure and function of organelles found in animal and plant cells. page 70 of 989 4 pages left in this module contents Principles of Biology 14 Eukaryotic Cells Components of a Eukaryotic Cell As we learned in the last chapter, prokaryotic cells are enclosed in a singular cellular membrane, while eukaryotic cells have additional internal membrane-bound organelles. Organelles compartmentalize cellular activities, allowing the eukaryotic cell to be larger and more complex than prokaryotic cells. The first organisms on Earth were much like some of today's prokaryotes. How did eukaryotic cells evolve from prokaryotic ones? According to the endosymbiotic theory, which we discuss later in this module, eukaryotic mitochondria originated as free-living prokaryotes that were engulfed by an ancestral eukaryote and became symbiotic. A similar but independent event is believed to have given rise to plastids such as chloroplasts. How other cellular organelles, such as the endoplasmic reticulum, evolved is less clear.