Week 3 Concepts: Metabolism Factors affecting Microbial Growth Prepare: Factors Affecting Microbial Growth The phase of the bacterial growth curve in which the rate of multiplication equals the rate of cell death is the ______. death phase telophase stationary phase lag phase exponential phase An organism that grows in lower pH conditions is called a ______. neutrophile acidophile Halophile barophile Alkalinophile An organism that uses organic carbon for its carbon needs and sunlight for its energy needs would be called a ______. heterotroph photoautotroph chemoheterotroph photohetrotroph halotroph Self-Check: Growth Requirements in Microorganisms Place the images in order from top to bottom to show extracellular digestion in bacteria and fungi. 1. 2. 3. 4. Self-Check: Sources of Energy Which type of organism will acquire energy from light and acquire nutrients via catabolism of organic compounds. photoheterotroph chemoautotroph chemoheterotroph Photoautotroph Which type of organism will acquire energy and Carbon via catabolism of organic compounds. chemoheterotroph photoautotroph photoheterotroph chemoautotroph Self-Check: Identify the Organism Organisms that live on dead animals and plants and digest food by secreting enzymes are called____. parasites autotrophs commensals saprobes Self-Check: Transport Processes Which type of solution will result in water entering the cell? hypertonic isotonic All of these are correct hypotonic Self-Check: Temperature Requirements Microorganisms that have a requirement for growth below 15°C are called __________. mesophile thermoduric psychrophiles psychrotrophs Self-Check: Patterns of Oxygen Utilization Which thioglycolate tube shows the growth of an obligate anaerobe. Tube 1 Tube 2 Tube 3 Tube 4 Self-Check: Population Growth Which phase of growth has limited nutrients and exponential death of cells? Lag phase Exponential growth phase Stationary phase Death phase Self-Check: Phases of Population Growth Match the following items to their corresponding description. Limiting factors intensify and cells begin to die at an exponential rate. Death phase Exists when organisms live in an obligatory but mutually beneficial relationship. Mutualism The time required by the bacteria to double. Generation time Newly inoculated cells require a period of adjustment. Lag phase Reflect: Factors Affecting Microbial Growth The methanogens, producers of methane gas, require environments that are extremely cold. have abundant oxygen and CO2. are anaerobic with hydrogen gas and CO2. are directly exposed to sunlight. are very acidic. The phase of the bacterial growth curve that shows the maximum rate of cell division is the ______. prophase lag phase exponential phase stationary phase death phase Bacteria living in a freshwater stream that are transferred to ocean water would gain water. be in an isotonic solution. be in a hypotonic solution. become dehydrated due to the loss of water. A saprobe differs from a parasite in that a saprobe cannot infect a human, but a parasite is always infectious. a saprobe is a fungus, but a parasite can be any type of microbe. a saprobe does not harm a host that it lives on, whereas a parasite does harm a host. a saprobe derive nutrients from dead plants and animals, but a parasite derives nutrients from living plants and animals. An organism that uses CO2 for its carbon needs and sunlight for its energy needs would be called a ______. chemoheterotroph halotroph saprobe photoautotroph heterotroph Match the following terms to their corresponding description. Use carbon dioxide as a carbon source but catabolize organic molecules for energy. Chemoautotrophs Oxygen is an absolute necessity for their survival and growth. Obligate aerobe Organisms cannot tolerate oxygen and will die in presence of oxygen. Obligate anaerobe Acquire energy from light and acquire nutrients via catabolism of organic compounds. Photoheterotrophs An organism with a temperature growth range of 45°C to 60°C would be called a(n) ______. psychrophile extremophile facultative psychrophile thermophile thermoduric microbe Enzymes Prepare: Enzymes Enzymes that function inside a cell are ______. endoenzymes constitutive enzymes regulated enzymes exoenzymes apoenzymes Enzymes can be regulated. True False The term used to describe all of the chemical reactions within a cell is ______. metabolism redox reactions catabolism phosphorylation cellular respiration Enzymes are composed of proteins sugars fats All of these are correct DNA Self-Check: The Role of Enzymes Enzymes lower the activation energy of a reaction. Self-Check: Factors Affecting Enzyme Activity Which of the following affect enzyme activity? concentration of reactants temperature concentration of enzyme pH all choices are correct Self-Check: Enzyme Structure Holoenzymes are complete and functional enzymes. These are made of protein components called apoenzymes as well as any required coenzymes/cofactors. Self-Check: Naming Enzymes Select the correct class for each drop-down based on the substrates and action provided. Enzyme Class Substrates Action Hydrolase Lactose Breaks lactose down into glucose and galactose Hydrolase Penicillin Hydrolyzes beta-lactam ring Transferase DNA nucleosides Synthesizes a strand of DNA using the complementary strand as a model Oxidoreductase Pyruvic acid Catalyzes the conversion of pyruvic acid to lactic acid Oxidoreductase Molecular oxygen Catalyzes the reduction of O2 (addition of electrons and hydrogen) Self-Check: Enzyme Location Your bacterium is growing on a type of medium called casein agar, which contains milk protein (casein). There is a clear zone around the growth area of the bacterium, showing that it is synthesizing the enzymes needed to catalyze the extracellular breakdown of casein. These enzymes are considered ______. ribozymes exoenzyme apoenzymes endoenzymes Self-Check: Enzyme Regulation Constitutive enzymes are always present in a cell. Self-Check: Enzyme Inhibition When enzyme action stops due to a buildup of end product that acts as a regulatory molecule, this control is called ______. enzyme induction noncompetitive inhibition enzyme repression competitive inhibition Reflect: Enzymes Enzymes lower the __________________. pH activation energy Reaction rate coenzymes temperature Match the following enzyme names with their reactions. cleaves bonds with addition of water hydrolase transfers electrons oxidoreductase changes isomeric form isomerase transfers functional groups transferase requires ATP and removal of water ligase When a molecule regulates the activity of an enzyme by binding to a site outside of the active site, it is known as a/an __________________. catalyst noncompetitive inhibitor apoenzymes cofactor competitive inhibitor A holoenzyme is a combination of a protein and one or more substances called ______. catalysts apoenzymes cofactors substrates ribozymes Enzymes that are retained and function inside of a cell are known as __________. constitutive enzymes apoenzymes regulated enzymes exoenzymes endoenzymes Increasing the amount of the enzyme will increase the ___________. pH temperature reaction rate coenzymes activation energy Binding of the substrate to the enzyme produces a/an _____________ complex. active site enzyme/substrate complex holoenzyme apoenzyme start site The formation of peptide bonds between amino acids to build a polypeptide is an example of ______. phosphorylation anabolism glycolysis fermentation catabolism The _____________structure of the enzyme dictates the binding site of the substrate. tertiary (3-dimensional) primary quartinary secondary A ______________ is an organic molecule needed to form a holoenzyme. ATP vitamins coenzymes cofactors enzymes The binding site for the substrate is the __________________. apoenzymes catalysts active site start site cofactors A/an __________________ will slow down or stop enzyme activity. Inhibitor Active site apoenzymes catalysts Cofactors A _________________mimics the shape of the substrate. catalyst apoenzymes noncompetitive inhibitor cofactors competitive inhibitor Metabolism Prepare: Metabolism During aerobic cellular respiration, the final electron acceptor is ______. pyruvic acid FAD oxygen cytochrome C nitrate The term used to describe the reactions which break down larger macromolecules into simpler molecules within a cell is ______. metabolism catabolism phosphorylation cellular respiration redox reactions The cell's metabolic reactions involve the participation of ______ that lower the activation energy needed for the initiation of a reaction. enzymes ATP vitamins cofactors coenzymes Self-Check: Metabolism of Microbes The formation of peptide bonds between amino acids to build a polypeptide is an example of ______. anabolism phosphorylation fermentation catabolism Glycolysis Self-Check: Glycolysis When glucose is broken down by glycolysis during bacterial fermentation, what is the usual net production of ATP? 2 3 24 36 38 Self-Check: Cellular Respiration Select the location of the process. Self-Check: Fermentation Fermentation ______. requires an organic electron acceptor requires oxygen only occurs in aerobic organisms is equivalent to aerobic respiration in ATP production is the same as anaerobic respiration Self-Check: Anaerobic Respiration Label the pathways. Reflect: Metabolism The formation of citric acid from oxaloacetic acid and an acetyl group begins ______. The Krebs cycle Glycolysis Mixed acid fermentation Alcoholic fermentation The electron transport system During anaerobic respiration a common final electron acceptor is _____. FADH2 NO3 glucose pyruvic acid oxygen Oxygen reacts with hydrogen to produce ______________in the electron transport chain. FADH2 NADH pyruvic acid glucose water As the electron transport carriers shuttle electrons, they actively pump _____ into the outer membrane compartment, setting up a concentration gradient called the proton motive force. hydrogen ions ATP oxygen phosphate NADH The reactions of fermentation function to produce _______ molecules for further use in glycolysis. pyruvic acid glucose NADH NAD+ ATP In the cell, energy released by electrons is often used to phosphorylate ______. pyruvic acid oxygen ADP NAD ATP In bacterial cells, the electron transport system is located in the ______. cytoplasm mitochondria cell membrane chloroplasts ribosomes The Kreb’s cycle generates the most ___________. NADH ATP pyruvic acid glucose NAD+ Match the following processes to the correct location. Mitochondria ETC in Eukaryotes Bacterial cell membrane ETC in Prokaryotes Cytosol Glycolysis in Eukaryotes and Prokaryotes The majority of ATP is formed during _________________. glycosysis processing of pyruvic acid for the Krebs cycle the electron transport chain All phases produce the same number of ATP molecules. the Krebs cycle
