Chapter 9 Flashcards
Cellular Respiration (29 cards)
What are oxidation-reduction reactions?
Essentially moving electrons around. Electrons are always transferred from one molecule to another.
What does it mean to oxidize a molecule?
To lose an electron.
What does it mean to reduce a molecule?
To gain an electron.
What is the relationship between electrons and energy in reduced compounds?
More electrons means more energy; reduced compounds are higher energy.
Why do we breathe out CO2?
Because we’ve extracted all the energy possible and it’s no longer useful, so it is a waste product.
What are NADH and FADH2?
Electron carriers that are easily reduced (gain electrons) and can be oxidized (lose electrons).
What are the main components of mitochondria?
Inner membrane and matrix.
What are the four main stages of cellular respiration?
Glycolysis, pyruvate oxidation, citric acid cycle, electron transport chain.
What are the inputs and outputs of glycolysis?
Input: glucose; Output: pyruvate, ATP, NADH.
What occurs during the first half of glycolysis?
Glucose is converted to 2 glyceraldehyde 3-phosphate and uses ATP.
What occurs during the second half of glycolysis?
Glyceraldehyde 3-phosphate is converted to pyruvate, producing ATP and NADH.
What is the output of pyruvate oxidation?
Acetyl CoA, CO2, and NADH.
What happens during the citric acid cycle?
Acetyl CoA binds with oxaloacetate, releasing CO2 and producing NADH, ATP, and FADH2.
Where do the CO2 products in the citric acid cycle come from?
From the oxidation of carbon-containing molecules.
What is the electron transport chain?
A series of complexes that transfer electrons from NADH and FADH2 to oxygen.
What complexes does NADH interact with in the electron transport chain?
Complex I, II, III, IV, and finally O2.
What is the role of FADH2 in the electron transport chain?
It brings electrons to complex II, bypassing complex I.
Which complexes pump H+ ions across the membrane in the electron transport chain?
Complexes I, III, and IV.
What is the function of ATP synthase?
Uses energy from H+ movement down its concentration gradient to catalyze formation of ATP.
What is fermentation?
The process of producing ATP without O2 as the final electron acceptor.
What happens during alcohol fermentation?
Pyruvate is converted to ethanol, skipping the citric acid cycle and ETC.
What is lactic acid fermentation?
Pyruvate is converted to lactate using NADH to replenish NAD+.
How does the liver store glucose?
As glycogen, which can be broken down into glucose when needed.
