complete solution (25 pgs)
fermentation - correct answer ✔Partial degradation of sugars or other
organic fuel that occurs without the use of oxygen
aerobic respiration - correct answer ✔Oxygen is consumed as a reactant
along with organic fuel
Most efficient catabolic pathway
Similar to the combustion of gasoline in an automobile engine after oxygen is
mixed with the fuel (hydrocarbons)
Food provides the fuel for respiration
Exhaust is carbon dioxide and water
anaerobic respiration - correct answer ✔Harvesting of chemical energy
without oxygen
cellular respiration - correct answer ✔Includes aerobic and anaerobic
processes
Cellular respiration is often used to refer to the aerobic process
catabolism - correct answer ✔Linked to work by a chemical drive shaft - ATP
,To keep working, the cell must regenerate its supply of ATP from ADP and Pi
oxidation-reduction reactions - correct answer ✔In a redox reaction, the loss
of electrons from one substance is called oxidation and the addition of
electrons to another substance is known as reduction
Adding electrons is called reduction
Reducing agent is the electron donor
Electron acceptor is the oxidizing agent
oxidation of organic fuel molecules during cellular respiration - correct answer
✔Oxidation of methane by oxygen is the main combustion reaction that
occurs at the burner of a gas stove
Respiration as a redox reaction
The fuel (glucose) is oxidized
Oxygen is reduced
Electrons lose potential energy along the way
Energy is released
, energy yielding foods - correct answer ✔Carbohydrates of fats
Reservoirs of electrons associated with hydrogen, often in the form of C-H
bonds
Only the barrier of activation energy holds back the flood of electrons to a
lower energy state
Without this barrier, a food substance like glucose would combine almost
instantaneous with O2
cellular respiration - correct answer ✔Cellular respiration does not oxidize
glucose in a single explosive step
Glucose is broken down in a series of steps, each one catalyzed by an
enzyme
At key steps, electrons are stripped from the glucose
Each electron travels with a proton, H+
Hydrogen atoms are not transferred directly to oxygen, but instead are usually
passed first to an electron carrier, a coenzyme
This coenzyme is well suited as an electron carrier because it can cycle easily
between its oxidized form NAD+ and its reduced form NADH