BIO 200 10/7/2026

Proteins - Structure and Function

Polymers are

repeating units of simple monomers that are covalently bonded together

When monomers undergo condensation

covalent bonds are formed between monomers as the hydroxide and hydrogen have their bonds broken from their own respective monomers.

When polymers undergo hydrolysis

the covalent bonds between the monomers are broken and are hydrogen is attached to one and a hydroxide is attached to another.

Proteins are polymers of ___ ___ that fold into specific shapes.

amino acids

Proteins are also referred to as ____ as they contain many peptide bonds.

polypeptides

enzymes typically have names that end with

- ase

Amino acids are ___ that assemble into proteins

monomers

Animo acids of proteins have two functional groups:

Amines and carboxylic acid

Amindo acids are covalently linked together to form a ___ ____

peptide bond - the carboxylic acid looses its oxygen and the anime looses two of its hydrogens during condensation, then the carbon in carboxylic acids bonds with the nitrogen of the anime.

Amino acids are categorized by the chemical properties of their ___ ___.

side chains (R groups)

the R group of the animo acids are whats connected to the ___ ___.

central carbon which has the carboxylic acid and anime bonded to it.

To recognize electrically charged side chains:

Notice on the R-group that there will be an element that has a charge of ±

To recognize polar side chains on the R-group:

there will be a ± dipole symbol

To recognize non-polar chain on the R-group:

They’re mainly hydrocarbon and there is no charge on the R-Group.

There are ___ different amino acids

20

In the lipid memebrane of a cell remember there is a hydrophobic and hydrogphillic area. This means that:

The integral protein is hydrophobic and the peripheral protein is hydrophilic.

There are ____ levels of animo acids

Primary, secondary, tertiary, quanternary

Primary structure of the order of the animo acids in the polypeptide is described at:

The scale of the primary structure is just the functional groups: animes, carboxylic acid, r-group

Secondary structure: hydrogen bonding between the non-variable parts of non adjacent animo acids. There are two shapes:

Alpha Helix and Beta Pleated sheet and they’re held together by hydrogen bonds.

Tertiary structure is determined by interactions between __ ___ with each other and the local environment.

side chains

Quaternary structure involves interactions between different polypeptides to form a ____.

multi-peptide protein

The process of protein folding is fast and spontaneous and take place as a protein makes these specific ___ ___.

intermolecular interactions

Methods to denature proteins

changes in temperature, solvent, pH, reducing agent

Structure ___ function.

Drives - if a protein loses its shape, it loses its function

Proteins are not ___ structures

rigid - There are constant variations.

Non polar side chains like hydrocarbons relation to water

hydrophobic and are likely to to cluster on the interior of proteins in water

side chain that isn’t a hydrocarbon (-OH or -NH2)

hydrophilic polar side chain. Located on the surface of the proteins where they can interact with water.

Charged side chains like (COO-)

these are charged and generally react with water so they favor the surface of proteins