BIOL 2051 EXAM 2 QUESTIONS WITH COMPLETE ANSWERS NEW VERSION

BIOL 2051 EXAM 2 QUESTIONS WITH COMPLETE ANSWERS NEW VERSION Sum of all catabolic and anabolic reactions - Answers metabolism Energy-producing reactions - Answers catabolic Biosynthetic (energy-using) reactions - Answers anabolic Oxidation Reduction (___) reactions - Answers redox Oxidation deals with the ___ of electrons. - Answers loss (OIL) Reduction deals with the ___ of electrons. - Answers gain (RIG) Explain redox reactions - Answers An electron donor transfers electrons to an acceptor. The donor become oxidized and the acceptor becomes reduced. What is NADH? Oxidized or reduced? - Answers reduced What is NAD+? Oxidized or reduced? - Answers oxidized What does an electron carrier do? - Answers help transfer electrons from donor to acceptor Why are NAD and NADH often referred to as coenzymes? - Answers they work so closely together ___ transfer of electrons from a donor to acceptor is not always possible. - Answers direct What does an enzyme do? - Answers convert substrate to product more efficiently The enzyme binds to the ___ - Answers substrate Explain NAD+ reduction. - Answers Enzyme I reacts with a substrate (electron donor) and oxidized form of coenzyme, NAD+. This then yields NADH and the substrate oxidized. What is the electron donor is the citric acid cycle? - Answers isocitrate A _____ is an enzyme that oxidizes a substrate by transferring one or more protons and a pair of electrons to an acceptor, usually NAD/NADP, FAD or FMN. - Answers dehydrogenase Explain NADH oxidation. - Answers Enzyme II reacts with the substrate (electron acceptor) and the reduced form of the coenzyme, NADH. This then yields NAD+ and the substate reduced. ___ is released from redox reactions. - Answers energu Energy is stored in ___ and transported wherever needed. - Answers molecules What are the two types of energy storage compounds? - Answers short term and long term What are the short term energy storage compounds? - Answers ATP and derivatives of coenzyme A What is considered the primary energy carrier in the cell? - Answers ATP What kind of bonds does ATP have? - Answers 2 phosphoanhydride bonds (high energy phosphate bonds) How can electron carriers be located? - Answers membrane-bound or freely diffusible What is an example of a membrane-bound electron carrier? - Answers Cytochrome C What is an example of a freely diffusible coenzyme electron carrier? - Answers NAD+/NADH Contains 2 phosphoanhydride bonds (high energy phosphate bonds) - Answers ATP How do derivatives of coenzyme A have energy? - Answers Thioester bonds. Thioester bonds release energy. (Not much energy, but still good energy.) What are examples of long term energy storage compounds? - Answers gylocogen, poly-b-hydroxybutyrate, elemental sulfur How does ATP have energy? - Answers Anhydride bonds between phosphate groups. If you break an anyhydride bond, you release energy. What is a chemooroganotroph's energy source? - Answers organic coumpounds (aka stuff with carbon) What processes do chemooroganotroph use to make energy? - Answers fermentation, aerobic respiration, and anaerobic respiration What is a chemolithotoph's energy source? - Answers inorganic compound What processes do chemolithotophs use to make energy? - Answers primarily aerobic respiration, but some are capable fo anaerobic respiration What are the 3 types of phosphorylation? - Answers substrate level phosphorylation, oxidative phosphorylation, photophosphorylation Describe substrate level phosphorylation. - Answers A phosphate group (PO4^3-) is removed from a subtrate and added to ADP to make ATP. Define phosphorylation. - Answers The transfer of a phosphate group to a molecule. Describe oxidative phosphorylation - Answers Inorganic phosphate (free PO43- ; Pi) is added onto ADP to make ATP by ATP synthase. Describe photophosphorylation. - Answers light-mediated oxidative phosphorylation (occurs in photosynthesis) The cell prefers ___ over any other sugar. - Answers glucose Why does the cell prefer glucose? - Answers It can go straight to glycolosis and make ATP ____ is a major pathway of glucose metabolism.. - Answers glycolosis __ ATP and ___ pyruvate are generated per glucose in glycolosis - Answers 2, 2 Where does gylcolosis occur? - Answers in the cytoplasm of cells capable of using glucose What goes into and comes out of glycolosis? - Answers IN - 1 glucose(6 carbon sugar), 2 ATP, NAD OUT- 2 pyruvate, 4 ATP, 2 NADH Net gain of 2 ATP Glycolosis occurs in what organisms? - Answers bacteria, eukarya, and prokaryotes Glycolosis is precursor to ___. - Answers fermentation and respiration In glycolosis, the glucose is broken into 2 3-carbons * - Answers * Compare fermentation and respiration. - Answers Both use energy released from redox reactions to make ATP. Contrast fermentation and respiration. - Answers Respiration has an electron acceptor present, while fermentation has no exogenous electron acceptor. Is fermentation aerobic or anaerobic - Answers anaerobic What serves as electron acceptors and donors in fermentation? - Answers organic compounds What time of phosphorylation is fermentation? - Answers substrate level If oxygen is present, the cell will prefer ___ over __. - Answers respiration, fermentation What's a great location in the body for fermentation to occur? Why? - Answers More bacteria in large intestine than anywhere else. Another name is a fermentation vessel. Bacteria here all perform fermentation. The ____ in fermentation would be the equivalent of pyruvate, - Answers oxidized compound ___ is a continuous cycle. NADH and NAD+ are converted back and forth. - Answers fermentation Fermentation notes.* - Answers - pretty much any molecule can be fermented - all create some sort of phosphate intermediate An organism can only to fermentation id - Answers they have the genes to code for the enzymes Cooperative relationship in which the microorganisms work together to degrade a compound - Answers syntrophy ____ can ferment butyrate to acetate for energy if a ____ is present to use the H2 generated - Answers Syntrophomonas, methanogen The organic molecule buterate isn't normally a fermentable molecule. What can happen? - Answers Syntrophomonas and methanogen can do syntropy Explain the syntropy between Syntrophomonas and methanogen - Answers Syntrophomonas must use FAD+ (just like NAD+) electron carrier. This came from the bacteria methanogen. Methanogen takes hydrogen from FADH and NADH. ATP is created and that is why they work together to make this happen. In many cases, the product of one organism's fermentation is ____ - Answers fermented by a second organism T/F there is only one kind of fermentation - Answers false Most yeast are ___ - Answers acidophiles Why are there bubbles in beer? - Answers yeast ate sugar and released ethanol and CO2 because they needed to regenerate NAD+ in glycolysis to keep cycle going Yeast does ___ fermentation - Answers alcoholic What comes in/out of homolactic fermentation? - Answers IN: glucose, ATP, NAD+ OUT: NADH, pyruvate, lactate Organisms that do homolactic fermentation have a gene in their genome that codes for ___ - Answers lactate dehydrogenase What happens to lactate? - Answers It is a waste product and it is not used by the cell. What organisms do homolactic fermentation? - Answers streptococcus and lactococcus What organism does heterolactic fermentation? - Answers leueconostoc Some anaerobic eukaryotes (flagellated protozoan ___) have ___ that oxidize pyruvate to generate ATP by substrate level phosphorylation - Answers Trichomonas; hydrogenosomes What is trichomonas? - Answers human pathogen, lives in urinary tract (STD) but can also live up to 48 hours on semen or urine on toilet seat