C1.1 HL Metabolic Pathways
No description yet. This curated deck is ready for daily study.
Card preview (11)
What is a metabolic pathway?
A series of enzyme-catalysed reactions where the product of one step becomes the substrate of the next.
How are metabolic pathways controlled?
By regulating enzyme concentration (gene expression) and enzyme activity (inhibition/activation).
What are the two main types of metabolic pathways?
Linear and cyclic pathways.
What is a linear pathway?
Has a defined start and end product, e.g. glycolysis.
What is a cyclic pathway?
The final product regenerates the first substrate, e.g. Krebs cycle or Calvin cycle.
Why are multiple enzymes required in a pathway?
Each step is specific and regulated, ensuring efficiency and control of metabolic flux.
How do genes regulate pathways?
Each enzyme is encoded by a gene that can be switched on/off to control the pathway.
How is ATP involved in metabolic pathways?
Acts as an energy supplier by phosphorylation of intermediates or driving endergonic reactions.
How are respiration and photosynthesis connected?
The products of one are the reactants of the other — forming an energy cycle of CO₂, O₂, glucose, and ATP.
What are examples of cyclic and linear pathways?
Linear: glycolysis, blood clotting cascade. Cyclic: Krebs cycle, Calvin cycle.
What is feedback inhibition in metabolic control?
The end product inhibits the first enzyme, preventing overproduction — a form of negative feedback.