KINGDOM MONERA Bacteria Lecture 2: Kingdoms Monera, Protoctista and Fungi Kingdom Monera Commonly called bacteria All monerans are unicellular All monerans are prokaryotes Prokaryotes: Single-celled organisms surrounded by a membrane and cell wall that LACK membrane bound organelles Bacteria Characteristics Prokaryotic Unicellular Some autotrophic Some heterotrophic Some chemotrophic Contain Cell Walls What do we mean by prokaryotic? Prokaryote Cell lack membranes around their nuclei 1
Two major groups of Kingdom Monera Archeabacteria Most primitive organisms on earth Found in very harsh environments Eubacteria True Bacteria Disease causing bacteria in this group Characteristics of Monera Monera can be divided into two main groups: 1) Archaebacteria - ancient bacteria - live in extremely harsh conditions 2) Eubacteria - true bacteria ARCHAEBACTERIA EUBACTERIA Methanogens Thermoacidophiles Chemosynthesizers Extreme Halophiles Live in oxygen free environments, produce methane (CH 4 ). Live in water than is very hot and acidic (ph 2 to 4), line the edges of hot springs Make carbohydrates using inorganic compounds as energy source, live in hot sulfur vents on ocean floor Live in extremely salty places, grow in water up to ten times saltier than the ocean Gram-positive Bacteria Have thick walls made of protein-sugar complex, turn purple when stained Gram-negative Bacteria Cyanobacteria Have extra layer of lipid outside cell wall and turn pink after staining Gram-negative monerans that perform photosynthesis (like plants) and release oxygen Classifying Bacteria Bacterial Arrangements 3 main shapes: 1. Bacilli (rod-shaped) 2. Cocci (sphere-shaped) Diplo- --pair of cells Strepto --Chain of cells Staphylo Cluster of cells 3. Spirilla (corkscrew-shaped) 2
1. SPHERE-SHAPED: COCCUS 2. ROD-SHAPED: BACILLUS Diplococcus - two Staphylococcus clusters Streptococcus strings Diplobacillus - two Streptobacillus - strings 3. CORK SCREW: SPIRILLUM Why learn about Bacteria? Some cause serious diseases: Pneumonia, tuberculosis, lyme disease, bubonic plague, food-borne illnesses Most are beneficial Intestinal bacteria (digest food and make vitamins) Break down dead organisms (decomposers) Industry: make cheese, yogurt, antibiotics Positive contributions of bacteria Decomposers Fix nitrogen into a useable form Food production yogurt, cheese, etc. Sewage Treatment Clean Oil Spills Negative effects of Monerans Disease Syphilis, gonorrhea, tuberculosis, strep throat, botulism, etc. Food Spoilage 3
ARCHAEBACTERIA KINGDOM MONERA Methanogens: Thermoacidophiles: Chemosynthesizers: EUBACTERIA Gram-positive: Gram-negative: Cyanobacteria: Questions???? Extreme Halophiles: Kingdom Protista Protists are difficult to classify. Four of the five Kingdoms are Eukaryotes Plant Animal Fungus Many are only distantly related to Difficult to classify because each other. Protista Many are more related to organisms in other kingdoms. Protists are difficult to classify. Protista is often called the junk drawer of the kingdoms. Eukaryotes that do not fit into any other kingdom: - Animal-like but not quite an animal - Plant-like but not quite a plant - Fungus-like but not quite a fungus Protista Not a really valid Kingdom Few real evolutionary relationships Contains Algae: plant-like protists Protozoa: animal-like protists Slime & Water molds: fungal-like protists 4
General Characteristics Eukaryotic Unicellular Some may live in colonies May be Autotrophic or Heterotrophic or Both Some are motile Appeared about 1.5 BYA Classified into Three Main Groups Animal-like heterotrophs capable of locomotion Plant-like photosynthetic autotrophs Fungus-like decomposers that reproduce by spores Some protists may exhibit both animal-like & plant-like characteristics All protists have a nucleus and are therefore eukaryotic. Protists are either plant-like, animal-like or fungus-like. Animal like protists Animal-like protists consume other organisms. Are called protozoans heterotrophs single-celled (unicellular) Most are free living but some are parasitic Have food and waste vacuoles for storing and digesting food Are capable of movement Contracticle vacuoles pump out excess water Not animals because animals are multicellular and animal like protist are single-celled Protist examples: Paramecium Animal-like protists - Examples 2. Paramecium Unicellular, slipper-shaped move by coordinated beating of many cilia aquatic - mostly found in ponds and streams usually do not cause diseases in humans 30 5
Animal-like protists - Examples 2. Paramecium - continued Feeding occurs in the funnel-shaped gullet (buccal cavity) where food is drawn in by external and internal cilia to form food vacuole Plant like protists Plant-like protists are Make their own food through photosynthesis (autotroph). single-celled, colonial (live together in colonies) Are photosynthetic Not plants because they have no roots, stems, or leaves ingests organic detritus and other small organisms like bacteria and other protozoans 31 Protist examples: Euglena A) Euglena- PLANT-LIKE PROTIST Cont d one celled alga that moves with one flagellum lives in fresh water reproduces asexually red eyespot near front end to find light Why? have chlorophyll and can make their own food ( ) autotroph 34 contains disk-shaped chloroplasts PLANT-LIKE PROTIST Cont d A) Euglena Continued- Fungus like protists Fungus-like protists decompose dead organisms. Heterotrophs. Are decomposers can move at some point in their life cycle whereas fungi cannot. organelle is the site of photosynthesis and gets its name from the presence of the green pigments (the chlorophylls) 35 6
FUNGUS-LIKE PROTIST Slime Molds: fungus-like protists that are consumers live in cool, damp places EX: forest floor feed on bacteria growing on rotting logs and decaying leaves some are parasites (very few) Questions???? 37 Kingdom Fungi Characteristics of Fungi Eukaryotic Most are Multicellular Heterotrophic nutrition by absorption Produce spores by sexual and asexual reproduction Cell wall made of chitin No movement: change location by growth of body or dispersion of spores The Characteristics of Fungi Fungi are NOT plants They are nonphotosynthetic They are eukaryotes They are nonmotile Most are saprobes (live on dead organisms) The Characteristics of Fungi Absorptive heterotrophs (digest food first & then absorb it into their bodies Release digestive enzymes to break down organic material or their host BREAD MOLD 41 42 7
The Characteristics of Fungi Important decomposers & recyclers of nutrients in the environment Most are multicellular, except unicellular yeast Lack true roots, stems or leaves UNICELLULAR YEAST MULTICELLULAR MUSHROOM 43 4 Reasons Fungi Are Different From Plants 1) fungi lack chlorophyll 2) fungi are not photosynthetic Saprophytefeeds on cannot produce their own food most are saprophytes dead/decaying some are parasites organisms 3) they never reproduce by seeds 4) most fungi have cell walls made of chitin Plant cell walls are made of what? cellulose Fungal Nutrition Heterotropic by absorption secrete digestive enzymes digest macromolecules outside the body absorb digested nutrients Three nutritional modes Saprophytic = digestion of dead organisms Parasitic = digestion of live organisms, causing disease Mutualistic = beneficial relationship for two independent organisms Saprophytes Parasites Mycorrhizae: Mutualism Between Fungus and Plant Roots 8
Applying Your Knowledge 1. Parasitic 2. Saprophtyic 3. Mutualistic Questions???? Which mode of nutrition A. Provides a benefit for the fungus and its host partner? B. Is shown by athlete s foot fungus? C. Involves digestion of dead organisms? 9