BioFound 1.5, Part 1 Chapter 3, C: Biological Molecules Proteins

What are the four types of biological molecules?

• Carbohydrates (sugar)

• Lipids

• Nucleic acids

• Proteins

What is a polymer?

Chains of smaller repeating molecules called monomers

What is a monomer?

The repeated molecules within a polymer

Which type of chemical reaction breaks down a polymer?

Hydrolysis

What type of chemical reaction builds new polymers?

Dehydration Synthesis (condensation)

What is Dehydration Synthesis? (condensation)

The chemical reaction that is used to make new polymers by forming a covalent bond between two hydrogen atoms and one oxygen atom

What is Hydrolysis?

The chemical reaction that is used to break down polymers into their building blocks by adding a water molecule (H20) to the bond, causing it to break apart

What is a peptide bond?

A special type of covalent bond that attaches amino acids to each other in a protein

What is a protein sequence?

The order of amino acids in a protein

What is the definition of a protein when it comes to polymers?

A protein is a polymer (long chain) of amino acids

What are the monomers called that protein is built of?

Amino acids

What are the three major parts of an amino acid?

• The Alpha Carbon (a single carbon atom)

• Amino Group (carbon-based)

  • Carboxyl group (a biological acid)

What is the fourth part of an amino acid?

A unique side chain

How many different kinds of amino acids are there?

20 different kinds

how many amino acids are polar? How many are non-polar?

10 and 10

What is the same about every non-polar amino acid?

Every single one has a nonpolar side chain

What is the major chemical property of a non-polar amino acid?

Each one is hydrophobic

What is a hydrocarbon?

A carbon and hydrogen bond (C-H bond)

What is the maid difference between non-polar amino acids and polar amino acids?

While all non-polar amino acids have nonpolar side chains, polar amino acids have different types of side chains both to non-polar amino acids and to each other

What are the characteristics of negatively charged amino acids? How do they participate in the structure and function of a protein?

Their side chains are acidic

They release a hydrogen ion when coming into contact with water (H20), leaving behind a negatively charged ion

What are the characteristics of positively charged amino acids? How do they participate in the structure and function of a protein?

Their side chains act like bases

They absorb hydrogen ions and become positively charged (H+)

What are the characteristics of uncharged polar amino acids? How do they participate in the structure and function of a protein?

Their side chains are hydrophilic but unchanged

These side chains will easily and frequently participate in chemical reactions that modify protein structure and function

What are the characteristics of non-polar amino acids? How do they participate in the structure and function of a protein?

Side chains are very hydrophobic, the more hydrocarbons the more hydrophobic the amino acid is

Helps to maintain protein structure using the hydrophobic effect

What does denature mean?

The process where a protein or nucleic acid loses its native 3-dimensional structure due to the disruption of weak interactions within the molecule

What can cause denaturization?

Heat, pH changes, or chemical exposure

What is a molecular chaperone?

Proteins that assist in the folding, assembly, and stabilization of proteins

How do molecular chaperones help proteins fold?

Molecular chaperones help form proteins by binding to and stabilizing partially or totally unfolded protein polypeptides until the polypeptide chain is fully synthesized, keeping it from forming incorrectly

Why are proteins never guaranteed to become a certain shape?

Because their three-dimensional structure is determined by the sequence of amino acids in their primary structure.

• The sequence is determined by the nucleotide sequence in the gene encoding the protein, which widely vary

How do differences in a protein’s shape regulate its function?

The shape of a protein is decided by its 4 levels of structure which dictate its function with a cell. If this shape is changed in an unnatural way, it makes the protein unable to perform its tasks correctly