Enzymes

​Chapter 3 Enzymes

By Thiaga Letchumi

• Enzymes are Biological Catalysts. They increase the rate of metabolic reactions.

• Almost all biological reactions involve Enzymes.

• Enzymes are globular proteins with a specific tertiary shape. They are usually specific to only one reaction.
  

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Multiple Choice

How does enzyme speed up a chemical reaction?

• By lowering the activation energy, the amount of energy needed for reaction to begin

• By increasing the activation energy

• By increasing the temperature of the reaction

• By increasing the amount of reactant available

Multiple Select

Cofactors may be which of the following

• Cations (positively charged metal ions, Activators)

• Organic molecules, Vitamins or vitamin products (Coenzymes)

• Prosthetic group that permanently binds to enzyme

• Enzyme inhibitors

Multiple Choice

Holoenzyme + Apoenzyme = Coenzyme (Cofactors)

• True

• False

Multiple Choice

The active site will undergo a conformational change when exposed to a substrate to improve binding.

• Lock and key mechanism

• Induced fit hypothesis

Multiple Choice

The enzyme active site is extremely sensitive to changes in pH and temperature.

• true

• false

Multiple Choice

Increasing enzyme concentration will increase rate of reaction as more reaction sites are available for the substrate.

• False

• True

Multiple Choice

Increasing substrate concentration will increase the rate reaction even when the enzyme active site is saturated.

• False

• True

Multiple Choice

Enzyme inhibitors block or distort the enzyme active site.

• True

• False

​Myasthenia gravis

​Neostigmine is a drug that used to treat the symptoms , by improving muscle strength. Its a competitive inhibitor of acetyl choline esterase

​Uses of Enzymes