Unit 4: Cellular Respiration Flashcards
Where does all the energy that we use on earth ultimately come from?
What do plants do with this energy?
The sun ☀️
Plants photosynthesize to produce glucose and oxygen
How are photosynthesis and cellular respiration related?
Both provide energy, both use some energy as heat
During energy conversions, some energy is lost as…
Heat 🔥♨️
What is the fundamental function of cellular respiration?
Generating ATP for cellular work
What is the balanced chemical equation for cellular respiration?
C6H12O6 + 6O2—6CO2 + 6H2O + ATP
Where is the energy available to a cell contained?
In the chemical bonds of food molecules
Where is the energy we get from glucose stored?
Chemical bonds
What is redox reaction?
Oxidation-reduction reaction the movement of electrons from one molecule to another
Oxidation vs. reduction
Why do oxidation and reduction always go together?
Oxidation: loss of electrons
Reduction: gain of electrons
Because electron transfer requires a donor and an acceptor
In cellular respiration, glucose is…and O2 is…
Glucose: oxidized
O2: reduced
What are the two key players in the process of oxidizing glucose? What does each do?
- Dehydrogenase: strips 2 hydrogen atoms from an organic molecule
- NAD+: made by cells to move electrons in redox reactions
When NAD+ picks up electrons that have been stripped from glucose, what does it become?
Is it the oxidized is reduced form?
Where does this molecule bring the electrons it has picked up?
NADH
It is reduced
It bring them to the Electron Transport Chain
What is the electron transport chain? What is it called?
O2 is found at the end of the ETC. It is called the final electron acceptor
What are the 3 main stages of cellular respiration and where do they occur in the cell?
- Glycolysis: occurs in cytoplasm
- Citric acid cycle: takes place in mitochondria
- Oxidative phosphorylation: occurs in ETC
What is reactant and final product of glycolysis?
Reactant: glucose
Product: 2 pyruvate
How does NAD+ become NADH during glycolysis?
Where does NADH go from there?
The cell reduces 2 molecules of NAD+
Goes to the ETC
How does ATP generated during glycolysis?
What is the net gain of ATP molecules from glycolysis?
Substrate level phosphorylation, an enzyme transfers a phosphate group from a substrate molecule directly to ATP which forms ATP
2 net ATP are gained for each glucose molecule that enters
Substrate level phosphorylation in glycolysis
An enzyme transfers a phosphate group from a substrate molecule durectly to ADP, forming ATP
Why is glucose the preferred molecule in cellular respiration?
It creates energy and is released in steps so not too much is released at once.
C-H bonds have lots of energy
How does glucose enter the cell?
Facilitated diffusion
How many ATP are invested in glycolysis?
2
What are the final products of glycolysis?
2 pyruvate, 2 net ATP and 2 NADH