Proteins Flashcards
What does a catalyst do ?
A catalyst speeds up the rate of chemical reactions and remains unchanged at the end of the reaction.
Since catalysts remain unchanged at the end of the reaction, what does this mean?
They can be used again
What is a biological catalyst also known as?
enzymes
How do biological catalysts speed up the rate of the reaction?
By lowering the energy input for a reaction to proceed.
What is the substance that an enzyme acts on called?
substrate
During the reaction, what is formed?
enzyme-substrate complex
What is the substance left behind at the end of the reaction called?
product
What is the substrate complementary to?
active site
What determines the shape of the active site?
sequence of amino acids
What happens to the shape of the enzyme when the substrate becomes bound to the active site?
changes shape, giving close fit between enzyme and substrate.
What happens after the substrate becomes bound to the active site?
substrate is broken down into end products
What happens to the shape of the enzyme once the end products have been released?.
returns back to original shape
What is degradation
A breakdown reaction - when a chemical compound splits into smaller parts.
What is synthesis
A build-up reaction - when two or more substances join together to form one product
What enzyme is specific to starch
Amylase
What are the products of the degradation of starch?
maltose
What enzyme is specific to the substrate glucose-1-phosphate?
phosphorylase
What type of reaction is there for glucose-1-phosphate using phosphorylase?
synthesis
What are the products of the synthesis of glucose-1-phosphate?
starch
What is the optimum temperature for the enzyme catalase ?
40’c
What name is given when an enzymes active site has changed shape?
denatured
Why might an enzyme become denatured?
At high temperatures once it has past its optimum.
What does an enzyme have in terms of the effect of pH?
different working range
How can we find the optimum pH for each enzyme?
In the middle of its working range
What do most enzymes work best at?(pH)
pH 7
What will happen to the enzyme if they are in a strong acid or alkali?
become denatured
Name the diff types of proteins
Hormones
Emzymes
Structural
Antibodies
Function and examples of hormones
Communication between different parts of the body.
Eg,insulin and glucagon
Function and examples of enzymes
speed up cellular reactions at body temperature
Eg, ATPase and Cellulose synthase:
Function and examples of structural proteins
Forms supporting frameworks inside cells
Eg,keratin and tubulin
Function and examples antibodies
Part of the immune system. They are produced by white blood cells
Eg,millions of diff types
Word equation for when liver cells produce the enzyme catalase to speed up the breakdown of hydrogen peroxide.
Hydrogen peroxide——>water + hydrogen
Catalase
What is a active site
The part of an enzyme that one or more substrates molecules can attach to
Three steps of degradation
- substrate colides with active site of enzyme and becomes attached.
- enzyme degrades substrate
- products released from active site
What is pepsin
Enzyme that breaks down proteins in the acidic conditions of the stomach
Whats pepsins optimum and working range ph
optimum of pH 2.5 and a working range of between pH 1-4
What is catalases optimum and working range ph
optimum pH of 9 and a working range of between pH 7-11.
What type of reaction is there for starch using amylase?
Degradation
