Lesson 7- Cellular Respiratory (Glycolysis, Preparatory Step) Flashcards
What is metabolism?
The sum of all chemical reactions occurring in an organism.
How many chemical reactions occur in a single cell at a time?
Thousands of reactions happen simultaneously
What is a metabolic pathway?
A sequence of chemical reactions where the product of one reaction serves as the substrate for the next.
What are the two types of metabolic pathways?
- Linear – A straight sequence of reactions.
- Cyclic – A repeating cycle of reactions.
What is the difference between anabolism and catabolism?
• Anabolism: Builds molecules, requires energy.
• Catabolism: Breaks down molecules, releases energy.
Give an example of an anabolic process.
Protein synthesis from amino acids.
Give an example of a catabolic process.
The breakdown of glucose into CO₂, H₂O, and ATP.
What is the role of enzymes in metabolism?
Speed up chemical reactions without being consumed
Can enzymes be reused?
Yes, enzymes are not consumed and can be reused repeatedly.
What are coenzymes?
Non-protein molecules that assist enzymes in moving molecules within reactions
Name two important coenzymes in energy production.
NAD⁺ and FADH₂
What is ATP?
Adenosine Triphosphate (ATP) is the main energy carrier in cells.
Where is energy stored in ATP?
In the high-energy phosphate bonds.
What happens when ATP is broken down?
ATP → ADP + Pi + Energy (energy is released for cellular work).
What is phosphorylation?
The addition of a phosphate group to ADP to regenerate ATP
What happens when glucose is fully broken down?
It produces CO₂, H₂O, and 36 ATP molecules
What do cells use for energy if glucose is unavailable?
Lipids and proteins can be broken down for ATP
What are the four stages of cellular respiration?
- Glycolysis (Cytoplasm).
- Preparatory Step (Mitochondria)
- Citric Acid Cycle (Mitochondria)
- Electron Transport Chain (Mitochondria)
Where does glycolysis occur?
In the cytoplasm.
What is the purpose of glycolysis?
To break down glucose (C₆H₁₂O₆) into two pyruvate molecules.
How many ATP are invested in glycolysis?
2 ATP molecules.
How many ATP molecules are produced in glycolysis?
4 ATP molecules (Net Gain = 2 ATP).
What are the two phases of glycolysis?
- Energy investment phase – Uses 2 ATP.
- Energy payoff phase – Produces 4 ATP and 2 NADH
What are the final products of glycolysis?
2 Pyruvate, 2 NADH, and 2 ATP (net gain)
