MICROBIOLOGY COMPREHENSIVE STUDY
SCRIPT VERIFIED QUESTIONS ANSWERS
ACCURATE SOLUTIONS PACK
●● What is the primary function of enzymes, and how are they
regulated?
Answer: Enzymes speed up chemical reactions. Most notably, the
enzyme is not consumed during the reaction and can be used repeatedly
by the cell. Enzymes can also be regulated by a cofactor such that in the
absence of the proper cofactor, enzymes are inactive while in its
presence enzymes are active.
●● What is the difference between catabolism and anabolism?
Answer: Catabolism is the process of breaking down larger molecules
into useful energy sources whereas anabolism is the building up or
biosynthesis od macromolecules from smaller molecular units into larger
complexes, most often associated with cellular growth and repair
●● ATP has the energy to ______, while ADP has the capacity to ______
energy.
Answer: Donate, accept
●● Chemotrophs can be subdivided into what two additional subgroups?
,Answer: Chemotrophs, which acquire energy from preformed chemicals
found in the environment, can be divided into either organotrophs
(removing electrons from organic molecules such as glucose) or
lithotrophs, which remove electrons from inorganic molecules
●● Chemotrophs utilize which form of phosphorylation?
Answer: Chemotrophs use oxidative phosphorylation (may also accept
substrate level phosphorylation). Oxidative phosphorylation utilizes the
energy released by the chemical oxidation of nutrients to reform ATP
●● What are the three distinct stages in the catabolism of glucose?
Answer: Glycolysis is the first step of this process and yields 2
molecules of ATP. Next, by either fermentation (or respiration) 2
additional molecules of ATP can be produces. Last, the electron transport
chain (ETC) produces 34 ATP via an oxidative phosphorylation event at
the plasma membrane.
●● What are the reactants of glycolysis?
Answer: Reactants are defined as any molecules present and involved at
the beginning of a specific chemical reaction (ie) glycolysis. In terms of
writing out a chemical reaction, the reactants are everything located to
the left of the arrow. The reactants of glycolysis are glucose, the co-
enzyme NAD+ and ATP.
●● How are the TCA and ETC related?
, Answer: The end products of the Kreb's (TCA) cycle are used to fuel the
electron transport chain. In other words, as the Kreb's cycle (TCA)
produces an abundance of reduced electron carriers (NADH and
FADH2), it fuels the ETC. As the electrons are transferred from
NADH/FADH2 to terminal electron acceptors a proton motor force is
generated, ATP synthase is activated and up to 34 molecules of ATP can
be produced.
●● In the absence of sugars, are entirely different metabolic pathways
used to process alternative sugar sources (fructose or lactose)?
Answer: No. Additional enzymatic steps are simply required at the
beginning of catabolism to convert complex sugars into usable forms of
either glucose or a glucose intermediate (glucose-6-phosphate)
●● Proteases are used to catabolize what?
Answer: Proteases are used to breakdown proteins (whereas lipases are
used to breakdown lipids)
●● Excluding sugars, what are the other sources of energy? Which is
highest in energy?
Answer: Carbohydrates, proteins, and lipids can all serve as potential
energy sources in the absence of sugar. Lipids are rich in energy, often
having several reduced carbon molecules (high in hydrogen content) that
can be used in both the TCA and ETC cycles
●● In what organelle does photosynthesis take place?