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48 terms

Microbiology test three

What is Metabolism?
Sum of all chemical processes (reactions) in a cell. Involves two opposite and complimentary processes.
What is Anabolism?
Synthesis of molecules. This process involves the use of energy. make little molecules big. So like reduction.
What is Catabolism?
Breakdown of molecules. This process involves the oxidation of a substrate molecule to produce energy. So it is like oxidation.
What is oxidation?
the loss of electrons so the oxidized molecule is a hydrogen donor. Has to happen in conjunction with reduction.
What is Reduction?
the gain of electrons so the reduced molecule is a hydrogen accepter. Has to happen in conjunction with oxidation
What are the two most common hydrogen accepters?
Can electrons exist alone?
No they can not they always form pairs so the reactions of oxidation and reduction always happen in pairs.
What is the most common molecule used in oxidative phosphorylation?
What are electrons used for?
energy transformations and the hydrogens (protons) to reduce another molecule
What are the two main energy sources that cells use
Sunlight and Chemical reactions
How do cells use sunlight as an energy source?
Photosynthesis. Have to have chlorophyl or else it does not work.
How do cells use chemical reactions as an energy source?
What does photosynthesis reduce?
reduces CO₂and forms carbohydrates
Reduction of CO₂ during photosynthesis results in the production of what ________?
What are the steps in protein synthesis?
1. mRNA takes part of the DNA of the cell from the nucleus to the cytoplasm.
2. rRN makes a templete of the gene
3. tRNA transfers the amino acid chain to the rRNA in the correct order. They are attached by hydrogen bonds.
4. Peptide bonds form between the amino acid sequence and the amino acid chain peels off of rRNA and the hydrogen bonds
5. The amino acid chain (protein) forms a specific shape that is held together by Double S- Bridge - Disulfide bonds..
What is a hydrogen accepter?
It is a reduced molecule such as NAD or NADP that accepts H. They are also called reductants. They are H sponges. They are necessary to gather the extra hydrogens so the electrons can go to the ETS
What two reactions are involved in all energy processes?
both oxidation and reduction have to occur because they work together in all energy processes
Which organisms can use oxygen as a final hydrogen acceptor?
Aerobic organisms
How many ATPs can be produced by the ETS from each electron pair produced in cellular metabolism?
4 electron pairs from Glycolosis resulting in 8 ATP and 15 electron pairs from Kreb's cycle resulting in 30 ATP for a total of 38 ATP.
What occurs in photosystem I and II?
Photosystem I: provides energy to reduce CO₂ → glucose (carbohydrate) CO₂ + e's → glucose + O₂+ H₂O the electrons come from Photosystem II where photolysis occurs and H₂O is oxidized into e's and H. In Photosystem II the H are picked up by NAD or NADH and the e's go to Photosystem I to reduce CO₂ and increase energy. They are dependant on each other.
What is the photolysis of water and why is it necessary in photosynthesis?
Photolysis of H₂O is the splitting of H₂O into H and e's in photosystem II providing the e's necessary for photosystem I to utilize to reduce CO₂ → Glucose.
Why is the presence of O₂ advantageous in producing a maximum amount of ATP from the oxidation of glucose?
It is important to have O₂ because oxygen + pyruvic acid begin the Krebs cycle which starts a series of reactions that produce 10 pairs of e's that are then transferred to the ETS producing 30 ATPS. Without the oxygen the process ends and only results in the production of 8 ATPs from glycolosis.
What is the hydrogen acceptor and final end product of fermentation?
it uses an organic molecule and produces alcohol with CO₂ as a byproduct.
Which portion of aerobic cellular respiration generates the maximum yield of ATP?
Kreb's cycle
Where does cellular respiration occur in bacteria what about in animal cells?
in the cytoplasm, in the mitochondria
What is the role of hydrogen bonds in protein synthesis?
temporary weak bonds that hold the new amino acid chain to the rRNA template.
What is the role of peptide bonds in protein synthesis?
permanant, Strong bonds that hold chain of amino acids together to form a protein strand.
What is the role of difulfide bonds in protein synthesis?
Bonds that form the shape of the proteins so they can interact with specfic substrates (lock and key)
What is the role of mRNA in protein synthesis?
messenger RNA gets the gene information from the DNA and delivers it to the rRNA in the cytoplasm.
What is the role of rRNA in protein synthesis?
ribosomal RNA forms the template to create the correct amino acid sequence (chain)
What the role of tRNA in protein synthesis?
transfer RNA gathers the correct amino acids and transfers them to the template (in the proper sequence)
Define a Saprophyte
they feed on decaying organic matter. where do you find these bacteria - compost pile
Define a Vector
usually arthropods, not affected by pathogen it carries and transmits the pathogen. ex: tics and fleas (middle man)
Define a reservior
a supply source of the pathogen. for example a deer has the pathogen in its blood
Define acid fast
Bacteria that you stain and then treat with an acid alcohol wash and it retains the stain.
Define pleomorphic
many forms shapes sizes. hard to identify probably because they dont have a cell wall.
Define obligate
must have or use another molecule to survive (use O₂)
Define facultative
can use O₂ or some other molecule as the Hydrogen acceptor will grow with or without O₂ either aerobic or anaerobic
°Genus Rickettsia kingdom Monera
°Obligate intracellular parasites
°Can't grow on artifical media but makes its own ATP
°(must grow in tissue culture chick embryos)
°Gram (-)
°"leaky" cell membrane allows loss of metabolites if
no host
°Transmitted by arthropod vector (ticks and fleas)
°EX: RMSF (Rocky Mountain Spotted Fever, Typhus)
°Obligate intracellular parasite
°Gram (-)
°Complex reproduction do not use binary fission
°Lack enzymes to produce ATP
°Have leaky membranes take in ATP - energy parasites
°Examples: bird infections humans get pneumonia and
°Smallest organism known capable of growth and reproduction outside of living host cells (self reproduction)
°Highly pleomorphic
°so small they pass through filters that easily trap bacteria
°PPLO groups
°Lack cell wall and penicillin resistant
°Organisms derived from bacteria with cell walls
°form if bacteria are exposed to penicillin - (penicillin inhibits cell wall formation)
°L = lacking cell wall
°Not viruses but paratisize other bacteria
°go into host between cell wall and emmbrane, eat, grow, divide, and leaves ghost cell (host) and reinfects
°Have their own parasites - bacteriophages (viruses that infect them)
°procaryotic but mold like because they have branching filaments
° broke into 3 genera - Actinomyces, Nocardia, and Streptomyces.
°obligate anarobes
°Gram +
°Branched filaments
°no spores
°lumpy jaw in cattle
°soil bacteria
°gram +
°some acid fast
°rarely pathogenic
°can produce antibiotics
What are Transovarian Transmissions?
mother tick to eggs, no vector necessary, mom is pregnant with eggs transfers to offspring and then the baby has it.