Enzymes and Macromolecules

Enzymes and denaturation
by unsuitable pH

Foundation Biology

14

Multiple Choice

What are the four biological molecules?

• proteins, carbohydrates, lipids, nucleic acids
• A, T, C, G
• water, air, earth, and fire
• oxygen, water, carbon, nitrogen

Multiple Choice

What is the monomer that makes up carbohydrates?

• Monosaccarides

• Fatty Acids

• Amino Acids

• Nucleotides

Multiple Choice

What are triglycerides made of?

• Monosaccarides

• Fatty Acids

• Amino Acids

• Nucleotides

Multiple Choice

What is the monomer that makes up proteins?

• Monosaccarides

• Fatty Acids

• Amino Acids

• Nucleotides

Multiple Choice

Amino acids all have the same general structure except for the:

• Amino Group
• Carboxyl Group
• 'R' Group
• Carbonyl Group

Multiple Choice

Which protein structure describes the sequence of amino acids?

• Primary structure

• Secondary structure

• Tertiary structure

• Quaternary structure

Multiple Choice

Which of the following describes the secondary structure of proteins?

• The sequence of amino acids

• The α-helix and β-pleated sheet folding

• The folding of the polypeptide chain due to the 'R' groups

• The joining of different protein molecules to make one big molecule

Multiple Choice

Which protein structure describes a protein's three-dimensional shape?

• Primary structure

• Secondary structure

• Tertiary structure

• Quaternary structure

Multiple Choice

Haemoglobin is a quaternary protein because:

• It has more than one peptide bonds

• Its shape is globular

• It consists of more than one polypeptide chains

• It has iron in each heme group

Multiple Choice

What is the monomer that make up nucleic acids?

• Monosaccarides

• Fatty Acids

• Amino Acids

• Nucleotides

Multiple Choice

Cellulose, starch and glycogen are examples of:

• monosaccharides

• disaccharides

• lipids

• polysaccharides

Multiple Choice

What does organic mean (in chemistry)?

• It costs more at the grocery store

• It contains carbon and hydrogen

• It is made of many individual parts

• It produces energy

Multiple Choice

What is the following molecule?

• triglyceride

• phospholipid

• steroid

• protein

Multiple Choice

What is the following molecule?

• alpha glcuose

• beta glucose

• amino acid

• disaccharide

Multiple Choice

What is the name of the special region of an enzyme that binds to the substrate? 

• Active area

• Unique site

• Complementary region

• Active site

Multiple Choice

Any substance that is acted upon by an enzyme is called a:

• Coenzyme

• Substrate

• Vitamin

• Polypeptide

Multiple Choice

After the enzyme and substrate bind together and perform the reaction, what does the substrate become?

• a substrate
• an enzyme
• a product
• an active site

Multiple Choice

At first, scientists thought that in order for an enzyme to catalyse a reaction, the substrate had to fit perfectly into the active site.

What was the name for this model of enzyme action?

• The original model

• The lock and key model

• The induced fit model

• The induced key model

Multiple Choice

We now know that in order for an enzyme to catalyse a reaction, the enzymes active site actually changes shape slightly as it binds to the substrate.

What do we call this model of enzyme action?

• The new model

• The lock and key model

• The induced fit model

• The induced key model

Multiple Choice

Pancreatic amylase is a digestive enzyme found in the small intestine. It helps break down large starch molecules later in the digestive process. Pancreatic amylase is unable to break down proteins.

Which of the following best explains why pancreatic amylase is able to break down starches, but not proteins?

• Enzymes are specific to their substrates

• Proteins are too large to be affected by enzymes

• Enzymes and proteins cannot break down other proteins

• Proteins are able to easily denture enzymes

Multiple Choice

An enzyme speeds up a reaction by:

• lowering the activation energy

• raising the activation energy

• releasing energy

• absorbing energy

​At low temperatures, molecules have little kinetic energy

As temperature increases, molecules gain kinetic energy, and have more chance of binding with enzyme

If the temperature is too high, the binding sites may be destroyed

​Reaction Temperature

Enzymes and denaturation by high temperature

Foundation Biology

12

Enzymes and denaturation
by unsuitable pH

Foundation Biology

14

Foundation Biology

17

Multiple Choice

Which of the following conclusions can be drawn from this graph?

• The optimum pH of the enzyme is 6.6.
  
• The optimum pH of the enzyme is 5.8
  
• The enzyme’s activity increases as pH increases 5.0 to 9.0
  
• The enzyme’s activity is greater around pH of 8.0 .
  

Multiple Choice

What effect does high temperature have on enzymes?

• Denatures them

• Inactivates them

• Destroys them