Internale Membranes & Enzymes (PPT 8) (U1) Flashcards
Define metabolism
- All the chemical reactions in a living thing.
What are the two types of reactions?
- Anabolic
- Catabolic
What is an Anabolic reaction?
Small molecules are combined to make larger molecules.
Energy is needed
What is a Catabolic reaction?
Large molecules broken down into smaller molecules.
Energy is given out
What are enzymes?
- Organic catalysts
- Proteins that can increase the rate a reaction occurs.
How many levels of structure do proteins have and what are they?
- 4
- Primary, Secondary, Tertiary, and Quaternary structure.
What is a primary structure?
Straight chains of AA bonded together by peptide bonds.
What is a secondary structure?
Coiling or pleating due to hydrogen bonding.
What is a tertiary structure?
3D folding due to bonding between attractions and repulsions between the special R group on each AA.
What is a Quaternary structure?
Where two or more proteins form protein aggregates.
What is the active site?
A cleft, groove or pocket on the surface of the enzyme that the substrate binds to.
What is a substrate?
The substance that binds to the enzyme.
Enzymes are ——- specific, this specificity —— from enzyme to ——-. (Fill in the blanks)
1- Substrate
2- varies
3- enzyme
When a substrate binds to an enzymes active site, a what is formed?
An enzyme-substrate complex.
What makes enzymes so substrate specific?
The complexity of the active site.
How do enzymes work?
It weakens the existing bonds to create new ones. Creating a new product entirely.
Do enzymes become apart of the reaction?
NO! They are simply facilitators. (Think of them like match makers)
What is the lock and key model, and what does it include?
A theory on how enzymes work.
The substrate was drawn into a closely matching cleft on the enzyme.
What is the Induced fit model, and what does it include?
A theory on how enzymes work.
The enzymes changes it shape slightly to force the substrate together or apart.
Name some similarities between the two theories. (At least 3)
- Theories on how enzymes work
- Both involve a substrate
- Both involve an active site
- Both speed up reactions
What is activation energy?
The amount of energy required for a reaction to occur.
How do enzymes speed up the rate of reaction?
The lower the amount of activation energy required for the reaction to take place.
What do catalyses do?
They speed up reactions by influencing the stability of bonds in the reactants.
Give an example of a catabolic reaction
- Digestion
- Cellular respiration
Give an example of a anabolic reaction.
Protein synthesis
Do enzymes have more than one use?
Yes! The enzyme can be re-used many times. But eventually will wear out and be replaced.
If a lipid enzyme is called Lipases.
And a protein enzyme is called proteases.
What are these called? Sucrose, Lactose, Urea
Sucrose= Sucroses
Lactose= Lactases
Urea= Ureases
Many enzymes are ——— in membranes. (Fill in the blank)
1- Embedded
The —– the surface are of a ——-, the more ——– can be embedded
1- Greater
2- Membrane
3- Enzymes
—— enzymes are often located in particular ——. Even within — regions of the ———. (Fill in the blanks)
1- Specific
2- organelles
3- particular
4- organelle
What are the factors that affect enzymes functions?
- Temperature
- pH levels
Why does Temp and pH affect the functions of the enzyme?
Because they change how to active site works, so the enzyme can no longer function.
How does temperature affect the enzyme?
The warmer the temperature, the faster molecules move. This increases the chance of them colliding and reacting.
Enzymes have an ——– Temp/ pH. (Fill in the blank)
1- optimum
What happens when the enzyme passes its optimum working conditions?
The enzyme can no longer work in those conditions, it becomes denatured.
What does it mean for an enzyme to become denatured?
The enzymes shape, therefore changing the active site so it can no longer bond with the substrate. These changes are irreversible.
What is a limiting factor?
Any factor that directly affects the rate of reaction that will occur.
Give three examples of a limiting factor.
- Temperature
- pH
- Substrate concentration
- Enzyme concentration
- Reactant products and co-enzymes
What is a co-enzymes job?
- To bind to enzymes that can’t bind to a substrate on their own.
What are the two types of inhibitors?
1- Competitive inhibitor
2- Non-competitive inhibitor
What do competitive inhibitors do?
They fit into the active site instead of the substrate. They are called competitive because they compete for the active site.
What do non-competitive inhibitors do?
They do not interfere with the active site. But they attach to the enzyme and change its shape, effecting its ability to work.
