Unit 22: Cellular Respiration Flashcards
(48 cards)
What are the three steps of the ADP-ATP cycle?
- ATP’s structure
- Energy release
- Regeneration
What is ATP’s structure?
First step of the ADP-ATP cycle. ATP consists of adenine and ribose sugar attached to three phosphate groups. The bonds between these phosphate groups, particularly between the second and third phosphates, store significant energy.
What is energy release?
Second step of the ADP-ATP cycle. When a cell needs energy, ATP is converted to ADP (adenosine diphosphate) by cleaving off the terminal phosphate group. This reaction releases energy that can be used for cellular processes.
What is regeneration?
Third step of the ADP-ATP cycle. ADP is then “recharged” back to ATP by adding a phosphate group, requiring energy input. This creates a continuous cycle of ATP breakdown and regeneration.
What are three differences between ADP and ATP?
- Structure- ATP has three phosphate groups, while ADP has only two.
- Energy state- ATP is the high-energy form, while ADP is the lower-energy form.
- Function- ATP provides energy for cellular processes, while ADP is essentially the “used” form waiting to be recharged.
What are catabolic pathways? (2 things)
- Involve the breakdown of complex molecules (like fats, carbohydrates, and proteins) into simple molecules.
- Often harvest stored chemical energy to produce ATP.
What are anabolic pathways? (2 things).
- Result in the synthesis of larger molecules from smaller components.
- Often use energy in the form of ATP.
What are two examples of molecules that catabolic pathways break down?
- Fats are broken down into glycerol and fatty acids.
- Proteins are broken down into amino acids.
What are four ways in which the products of catabolism are used for anabolic pathways?
- Citric acid cycle intermediates
- Glycolysis intermediates
- Through Acetyl-CoA
- Through Pyruvate
How are citric acid cycle intermediates used to support anabolic pathways?
Can be used to make amino acids.
How is acetyl-CoA used to support anabolic pathways?
Used to synthesize fatty acids for phospholipids and fats.
How is pyruvate used to support anabolic pathways?
Can be used in gluconeogenesis to make glucose for glycogen or starch.
How are glycolysis intermediates used to support anabolic pathways?
Help make nucleotides for DNA/RNA.
What is cellular respiration?
Cellular respiration is the process by which cells break down glucose to produce ATP, the energy currency of cells. This process occurs in four interconnected stages.
What are the four interconnected stages of cellular respiration?
- Glycolysis
- Pyruvate processing
- Citric acid cycle (Krebs cycle)
- Electron transport chain
Where does glycolysis occur?
In the cytoplasm of the cell.
What are the four inputs of glycolysis?
1 glucose, 2 ATP, 2 NAD⁺, and 2 Pi (inorganic phosphate).
What are the four outputs of glycolysis?
2 pyruvate, 2 ATP (4 produced, 2 used), 2 NADH, and 2 H₂O.
What is the net ATP gain from glycolysis?
2 ATP
What are the two steps to the overall process of glycolysis?
- Glucose (6-carbon) is broken down into two 3-carbon pyruvate molecules.
- Occurs in two phases: energy investment phase and energy payoff phase.
Where does pyruvate processing occur?
In the mitochondrial matrix.
What are the three inputs of pyruvate processing?
2 pyruvate molecules (from glycolysis), 2 NAD⁺, 2 CoA
What are the three steps in pyruvate processing?
Each pyruvate is converted into acetyl-CoA, producing CO₂ and NAD+ is reduced to NADH.
What are the three outputs of pyruvate processing?
2 acetyl-CoA, 2 CO₂, and 2 NADH.
