Enzymes

How do you know the liver enzyme catalase broke down the hydrogen peroxide?

Bubbles form (oxygen) and water remains at the bottom of the test tube

What might have an effect on the rate of reaction (what change in conditions)?

If there is a difference in temperature or pH.

When the enzyme reacts with the substrate, what is formed?

products

The substance with which an enzyme reacts is its...

substrate

What is the area of the enzyme where it binds t the substrate called?

the active site

What other two factors affect enzyme function beside temperature and pH?

the concentration of enzyme and the concentration of the substrate

What is the substance that enzymes bind to called?

the substrate

Breakdown of hydrogen peroxide by catalase in the human body

2H2O22H2O+ O2 hydrogen peroxide (arrow: catalase) water + oxygen

In what way does an enzyme affect the reaction it catalyzes? How does the enzyme produce this effect?

An enzymes increase the rate of reaction it catalyzes. It does this by combining with the substrate to form a highly reactive enzyme-substrate complex. When the reaction is completed, the enzyme and newly formed reaction product separate.

Why do cells use different enzymes to catalyze different reactions?

Cells must use different enzymes to catalyze different reactions due to the specification of the enzymes. Each enzyme has a shape specific to the shape of its substrate. Cells use different enzymes to catalyze different reactions depending on what types of molecules are being dealt with. For instance, there are different enzymes to break down proteins (protease), fats (lipase), and carbohydrates (amylase).

What is the relationship among enzymes, energy, and reaction rates?

Chemical reactions cannot proceed without a certain level of energy, the activation energy. Typically, temperatures in a cell are not high enough to provide activation energy. Enzymes speed up the rate of reactions by lowering their activation energies.

Is an enzyme "used up by the reaction it catalyzes? Explain.

Enzymes are not used up by the reactions they catalyze. During a reaction, an enzyme combines loosely with its substrate. When the reaction is finished, the two separate, leaving the enzyme unchanged.

What are enzymes? Why are enzymes essential to life?

Enzymes are usually proteins that speed up the rates of chemical reactions (catalysts). Typically, an enzyme is specific for a chemical reaction. Without enzymes, chemical reactions would proceed too slowly for life to exist. Enzymes are proteins that permit reactions to occur. Since enzymes are also catalysts, they allow an increase of rate of reaction. They do this by lowering the cell's high activation energy. Enzymes are important to life because they break apart molecules, put them together, and rearrange them. Without enzymes, bodily functions, essential to life, would be slowed down, to the point where the body wouldn't benefit. Enzymes help the immune and digestive system to function along with helping all cell functions to transpire.

How do enzymes help accelerate reactions?

Enzymes lower the activation energy needed for a chemical reaction.

What is the rate of reaction with a piece of liver?

Faster than the potato (since animals are more complex than plants)

What is the purpose of the sand in the first test tube?

It acts as the control in the experiment and has NO reaction.

What is the purpose of the liver breaking down catalase?

It breaks down a toxin (leads to the creation of a product from a reaction of binding to its substrate)

Could life exist without enzymes? Explain.

It could not exist, because biochemical reactions of the life processes do not occur rapidly enough without enzymes to sustain life. If enzymes did not exist, then the body would not be able to function all together, as process, vital to life, would be slowed down. These processes include all cell function, muscle movements, and digestion.

What do enzymes do for our cells in regards to activation energy?

Lowers it

Are enzymes used up when they are involved in a cell's chemical reactions?

No, you can reuse them

What is the rate of reaction with a piece of potato?

Not as fast as the liver (slower side)

What are some examples of digestive enzymes?

Protease (proteins), Lipase (lipids), Amylase (carbohydrates)

What would happen to biochemical reactions if enzymes were not involved?

Reactions would take place too slowly for the body to benefit

What is meant by enzyme specificity?

The active site on the enzyme has a complex configuration with which only the substrate molecule fits. Thus, the enzyme forms a complex with only one type of molecule. LOCK AND KEY CONCEPT

What happens to an enzyme if the pH or temperature are too high?

The enzyme break down or denature.

What is the active site of an enzyme?

The part of the enzyme into which the substrate fits

How does increasing substrate concentration affect the rate of enzyme action when enzyme concentration remains constant?

The rate of enzyme action increase up to a certain point, but above that point it remains constant and plateaus, no longer affecting the rate of enzyme action.

How does increasing enzyme concentration affect the rate of enzyme action when the substrate concentration remains constant?

The rate of enzyme action increase up to a certain point, but above that point it remains constant and plateaus.

How are carbohydrates and proteins broken down by enzymes in the mouth and stomach?

They break apart bonds holding the molecules together

Why are enzymes important to out body functions?

They break molecules apart, put them together, or rearrange them

Acting as catalysts, what do enzymes do to biochemical reactions?

They speed them up

Were we able to reuse the chicken liver on fresh hydrogen peroxide?

Yes, it was taken out of one test tube and put into another one, breaking down fresh hydrogen peroxide. This is because enzymes are reusable

What is activation energy?

energy required for a reaction to start

When activation energy is lowered, what happens to the rate of reaction?

it increases