ch.7 cellular respiration Flashcards
how do autotrophs obtain energy?
they capture energy and build organic molecules through photosynthesis
how do heterotrophs obtain energy?
they use organic molecules for energy and to build new organic molecules
how do all organisms extract energy from organic molecules?
cellular respirations
what type of reaction is cellular respiration?
redox reaction
How does NAD+ become NADH?
by accepting two electrons and one proton
what is the goal of cellular respiration?
to generate a lot of atp
what is aerobic cellular respiration?
cellular respiration where the final electron acceptor is oxygen
what is anaerobic cellular respiration?
cellular respiration where the final electron acceptor is an inorganic molecule
what is fermentative cellular respiration?
cellular respiration where the final electron acceptor is an organic molecule (lactate or ethanol)
What happens to electrons during respiration?
they are shuffles via electron carriers to a final electron acceptor
what is another word for aerobic respiration?
exergonic
the change of gibbs free energy = ….
the change in enthalpy - (temp) (change in entropy)
what is enthalpy?
the sum of the internal energy and the product of its pressure and volume
what is the equation of cellular respiration?
C6H12O6 + 6O2 —> 6CO2 + 6H2O
what is delta G?
the change in free energy
what is the DG for cellular respiration?
- 686kcal/mol of glucose
what is the main outcome of cell resp?
transfer of energy in making atp
what happens to energy in cell resp?
it is released from redox reactions as electrons drop from high to lower energy levels
What do electron transport chains do?
shuttle electrons via electron carriers
what are the two ways that cells make ATP from ADP and Pi?
substrate-level phosphorylation and oxidative phosphorylation
what is substrate-level phosphorylation?
transferring a phosphate directly from another molecule to ADP
what is oxidative phosphorylation?
use of a membrane bound atp synthase enzyme and a proton gradient
what is another name for oxidative phosphorylation?
chemiosmosis
what does the enzyme do in substrate-level phosphorylation?
directly transfers from the substrate(PEP) to ADP
what is the function of ATP synthase?
uses a proton gradient(H+) to produce atp from adp and pi
what are the five steps of glucose oxidation?
1.Glycolysis (cytosol)
In mitochondria
2. pyruvate oxidation
3. Krebs cycle
4. Electron Transport Chain
5. Chemiosmosis (ATP synthase and H+ gradient)
what does glycolysis do?
converts glucose to 2 pyruvates
what is glycolysis?
-a 10-step biochemical pathway that occurs in the cytoplasm
how are 2 ATP molecules produced in glycolysis?
substrate level phosphorylation and 2 NADH by reduction of NAD+
what does each NADH produced in glycolysis translate to?
3 atps being made by atp synthase by the electron transport chain
what must happen for glycolysis to continue?
NADH must be regenerated to NAD+ by either fermentation or aerobic respiration
what is aerobic respiration?
uses O2 as the final electron/H+ acceptor forming metabolic water