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Spring Online Lab 17
Pharmacology (NUR 3145)
Santa Fe College
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PROTISTA) study guide
Objectives:
Describe the basic structures of a bacterial cell. State the three domains of life. Name the shape of a given bacteria specimen. Be able to grow and count bacteria cultures State the domain of cyanobacteria. Be able to identify the cyanobacteria examples viewed in lab. State the domain of the protista. Be able to recognize the protista specimen viewed in lab. Identify protista as photosynthetic or heterotrophic.
Introduction:
I. KINGDOM BACTERIA
Bacteria evolved some 600 million years ago and were probably responsible for the production of the earth's atmosphere (cyanobacteria). Bacteria were discovered in the 17th century after the development of the microscope. Bacteria are prokaryotes that, along with several other distinctions, have peptidoglycan in their cell wall. These unicellular organisms are incredibly diverse and involved in all ecological processes across every ecosystem. Though most are too small to see with the naked eye and thus easily overlooked, some bacteria, such as the myxobacteria (in the order Myxococcales), collaborate to produce multicellular structures. In Figure 1 we have a few phyla for Bacteria with their representative organisms.
PROTISTA) study guide
Figure 1: Chlamydia, Spirochetes, Cyanobacteria, and Gram-positive bacteria are described in this table.
Characteristics of Prokaryotes
There are many differences between prokaryotic and eukaryotic cells. However, all cells have four common structures: a plasma membrane that functions as a barrier for the cell and separates the cell from its environment; cytoplasm, a jelly-like substance inside the cell; genetic material (DNA and RNA); and ribosomes, where protein synthesis takes place. As shown in Figure 2, prokaryotes come in various shapes, but many fall into three categories: cocci (spherical), bacilli (rod-shaped), and spirilla (spiral-shaped).
PROTISTA) study guide
Figure 3. The features of a typical prokaryotic cell.
The structure of prokaryotes Prokaryotes (domains Archaea and Bacteria) are single-celled organisms lacking a nucleus. They have a single piece of circular DNA in the nucleoid area of the cell. Most prokaryotes have a cell wall that lies outside the boundary of the plasma membrane. Some prokaryotes may have additional structures such as a capsule, flagella, and pili. In Table 1 we can see some structural similarities between Bacteria and Archaea.
Table 1. Structural Differences and Similarities between Bacteria and Archaea Structural Characteristic
Bacteria Archaea
Cell type Prokaryotic Prokaryotic
Cell morphology Variable Variable
Cell wall Contains peptidoglycan Does not contain peptidoglycan Cell membrane type Lipid bilayer Lipid bilayer or lipid monolayer Plasma membrane lipids
Fatty acids Phytanyl groups
Bacteria and Archaea differ in the lipid composition of their cell membranes and the characteristics of the cell wall. In archaeal membranes, phytanyl units, rather than fatty acids, are linked to glycerol. Some archaeal membranes are lipid monolayers instead of bilayers. The domain Archaea can be found in areas where it is hot, salty, low oxygen, and acidic environments, which means that it can live in extreme environments.
PROTISTA) study guide
The cell wall is located outside the cell membrane and prevents osmotic lysis. The chemical composition of cell walls varies between species. Bacterial cell walls contain peptidoglycan. Archaean cell walls do not have peptidoglycan, but they may have pseudopeptidoglycan, polysaccharides, glycoproteins, or protein-based cell walls. Bacteria can be divided into two major groups: Gram positive and Gram negative, based on the Gram stain reaction. Gram- positive organisms have a thick cell wall, together with teichoic acids. Gram-negative organisms have a thin cell wall and an outer envelope containing lipopolysaccharides and lipoproteins.
II. KINGDOM PROTISTA
Protists are a group of all the eukaryotes that are not fungi, animals, or plants. As a result, it is a truly diverse group of organisms. The eukaryotes that make up this kingdom, Kingdom Protista, do not have much in common besides a simple organization. Protists can look quite different from each other. As shown in Figure 4, some are tiny and unicellular, like an amoeba, and some are large and multicellular, like seaweed. However, multicellular protists do not have highly specialized tissues or organs. This simple cellular- level organization distinguishes protists from other eukaryotes, such as fungi, animals, and plants. There are thought to be between 60,000 and 200,000 protist species, and many have yet to be identified. Protists live in almost any environment that contains liquid water. Many protists, such as algae, are photosynthetic and are vital primary producers in ecosystems. Other protists are responsible for a range of serious human diseases, such as malaria and sleeping sickness. The term Protista was first used by Ernst Haeckel in 1866. Protists were traditionally placed into one of several groups based on similarities to a plant, animal, or fungus: the animal-like protozoa, the plant- like Protophyta (mostly algae), and the fungus-like slime molds and water molds. These traditional subdivisions, which were based on non-scientific characteristics, have been replaced by classifications based on phylogenetics (evolutionary relatedness among organisms). However, the older terms are still used as informal names to describe the typical characteristics of various protists.
PROTISTA) study guide
Groups of Protists (Classify protists into unique categories)
In the span of several decades, the Kingdom Protista has been disassembled because sequence analyses have revealed new genetic (and therefore evolutionary) relationships among these eukaryotes. Moreover, protists that exhibit similar morphological features may have evolved analogous structures because of similar selective pressures—rather than because of recent common ancestry. This phenomenon, called convergent evolution, is one reason protist classification is so challenging. The emerging classification scheme groups the entire domain Eukarya into six “supergroups” that contain all the protists as well as animals, plants, and fungi that evolved from a common ancestor. Each of the supergroups is said to be monophyletic, meaning that all organisms within each supergroup are believed to have evolved from a single common ancestor, and thus all members are most closely related to each other than to organisms outside that group. These six supergroups may be modified or replaced by a more appropriate hierarchy as genetic, morphological, and ecological data accumulate. This diagram below shows a proposed classification of the domain Eukarya. Currently, the domain Eukarya is divided into six supergroups. Within each supergroup are multiple kingdoms. Although each supergroup is believed to be monophyletic, the dotted lines suggest evolutionary relationships among the supergroups that continue to be debated.
PROTISTA) study guide
Figure 5: This diagram shows a proposed classification of the domain Eukarya. Currently, the domain Eukarya is divided into six supergroups. Within each supergroup are multiple kingdoms. Dotted lines indicate suggested evolutionary relationships that remain under debate.
PROTISTA) study guide
Plague Yersinia pestis
Fill out Prokaryotic cell above: 1-Chromosome (DNA) 2-Capsule 3-Cell Wall 4-Cell Membrane 5-Flagellum 6- Plasmid (DNA) 7-Ribosome 8-Pili 9- Nucleoid Region
Procedure 17: Bacteria culture:
By looking closely at the colonial growth on the surface of a solid medium, characteristics such as surface texture, transparency, and the color or hue of the growth can be described. The following three characteristics are readily apparent whether you are looking at a single bacterial colony or more dense growth, without the aid of any type of magnifying device. Texture—describes how the surface of the colony appears. Common terms used to describe texture may include smooth, glistening, mucoid, slimy, dry, powdery, flaky etc.
PROTISTA) study guide
Transparency—colonies may be transparent (you can see through them), translucent (light passes through them), or opaque (solid-appearing). Color or Pigmentation—many bacteria produce intracellular pigments which cause their colonies to appear a distinct color, such as yellow, pink, purple or red. Many bacteria do not produce any pigment and appear white or gray.
Bacteria Description:
Image below shows a close-up of colonies growing on the surface of an agar plate. In this example, the differences between the two bacteria are obvious, because each has a distinctive colonial morphology. Using microbiology terms, describe fully the colonial morphology of the two colonies shown above. A full description will include texture, transparency, color, and form (size, overall shape, margin, and elevation).
PROTISTA) study guide
Anabaena:
Gleocapsa:
Procedure 17: Eukaryotic supergroup table:
Fil out the table below with information of each protist
Supergroup Group members Characteristics 19. Excavata Diplomonads, Parabasalids, and Euglenozoans.
It identified and distinguished from other organisms 20. Archaeplastida Red algae, Chlorophytes, charophytes, land plants.
It has red algae and green algae
- Chromalveolata Dinoflagellates, Apicomplexans, Ciliates, Diatoms, Golden algae, Brown algae, Oomycetes
They have the presence of cellulose in most cell walls
- Rhizaria Cercozoans, Forams, Radiolarians Includes many of the amoebas, most which have threadlike or needle-like pseudopodia
- Amoebozoa Slime molds, Gymnamoebas, Entamoebas
Organisms are unicellular, which are made up of a single cell 24. Opisthokonta Nucleariids, Fungi, Choanoflagella tes
It includes animal-like choanoflagellates, which resemble a common ancestor of sponges
Procedure 17: Protist:
For the following names of Protist paste a picture of each (for example: type in google “volvox aureus microscope picture” and most pictures are going to be form under a microscope). Give me method of locomotion: nonmotile, gliding, pseudopods, flagella, or cilia. You should add other key facts that will help you remember the protist, for example if they cause disease. Adapted from: courses.lumenlearning/suny-wmopen- biology2/chapter/groups-of-protists/)
PROTISTA) study guide
Name Supergroup Locomotion Draw Other comments Amoeba Amoebozoa Pseudopod s
widely distributed and commonly found on the bottom mud or on the underside of aquatic vegetation in freshwater, ponds, ditches, lakes, springs, slow running streams is often found in relatively clean ponds with highly oxygenated freshwater.
- Paramecium Chromalve ola ta
cilia Is widespread in freshwater, brackish, and marine environme nts and are often very abundant in stagnant basins and ponds. 26. Plasmodium malariae
SAR:
Alveolata
nonmotile Unusual characteris tics of this organism compare to general eukaryotes include the rhoptry, microneme s, and polar rings near the apical end.
PROTISTA) study guide
PROTISTA) study guide
32.
Foramaminifera
Rhizaria pseudopod s
Are a single- celled organisms, characteriz ed by streaming granula ectoplasm for catching food and other uses. 33. Trichonomas vaginalis
Excavata flagella Is a parasitic protist and it is a human pathogen that one in 30 women tests positive for this parasite. 34. Vorticella Chromalveol ata
cilia It has a unique structure of vorticella that distinguishes them from other ciliates.
- Chlamydomonas
Archaeplasti da
flagella A genus of green algae that is found in stagnant water and on damp soil. It is used as a model for molecular biology 36. Plasmodium Chromalveol ata
Gliding It is within the order haemosporida, a group that includes all apicomplexan s that live within blood cells.
PROTISTA) study guide
- Amoeba Model Image
PROTISTA) study guide
What is the function of the eyespot of Euglena? It is a heavily pigmented region in certain one-celled organisms that apparently functions in light reception.
Does Paramecium rotates as it moves? It can rotate around its axis and move in the reverse direction on encountering an obstacle.
What do you suppose the living Amoeba is moving toward or away from? The amoeba moves towards its prey, its pseudopods reach out, surround, and engulf the food inside the cell membrane of amoeba proteus by forming a food vacuole.
Spring Online Lab 17
Course: Pharmacology (NUR 3145)
University: Santa Fe College
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