KA6-Cell Metabolism Flashcards
What is cell metabolism?
All the biochemical reactions that occur in a living cell.
What is a metabolic pathway?
A metabolic pathway is a pathway to a product, regulated by enzymes that catalyse specific reactions.
State the types of pathways involved in a metabolic pathway.
Reversible and irreversible pathways, which help with the control and alternative routes that allow steps to be bypassed.
What is an anabolic reaction?
Build up of larger molecules from small molecular and requires energy.
What is a catabolic reaction?
The break down of large molecules into smaller molecules and releases energy.
How are metabolic pathways controlled?
Each step in a metabolic pathway is controlled by a specific enzyme.
What happens if a pathway is a interrupted by the lack of a particular enzyme?
The pathway will stop, preventing the next metabolite being produced, which will result in the accumulation of the previous metabolite.
What is activation energy?
The energy needed to break bonds and start a reaction.
What is specificity?
When a substrate is specific to its enzyme and it’s shape is complementary to the active site.
What is induced fit?
Induced fit occurs when the active site changes shape to better fit the substrate after it binds.
What is affinity?
Affinity=Chemical Attraction
A substrate has high affinity, compared to a product, which has low, allowing it to leave the active site.
From what is the direction and rate of enzyme reaction affected by?
Substrate concentration and end product concentration.
How does substrate concentration have an affect on enzyme activity?
As substrate concentration increases, the rate of reaction also increases, until a point where enzyme concentration becomes a limiting factor.
What is an inhibitor?
An inhibitor is a substance that reduces the rate of an enzyme reaction.
Describe competitive inhibition.
A competitive inhibitor competes with a substrate for the active site. They directly bind at the active site preventing the substrate from binding. Competitive inhibition can be reversed by increasing substrate concentration.
