Introduction to Biochemistry: Amino Acids and Proteins

These flashcards cover key concepts from the introduction to biochemistry concerning amino acids, their structure, classification, and the role they play in protein formation.

What are amino acids often referred to as in biochemistry?

The alphabet of biochemistry.

How many amino acids are there?

20 amino acids.

What is one common effect of amino acid deficiency?

Most diseases are associated with some sort of amino acid deficiency.

What are the three main parts of an amino acid?

Amine group, carboxylic acid group, and side chain.

What is the term for the central carbon atom in an amino acid?

Alpha carbon.

What distinguishes one amino acid from another?

The side chain (R group) attached to the alpha carbon.

What type of amino acids can the body synthesize?

Non-essential amino acids.

What are the amino acids that must be obtained through diet called?

Essential amino acids.

In the book of Daniel, what specific type of food did Daniel request?

Pulse.

What is a zwitterion?

A molecule that has both positive and negative charges.

What happens to amino acids at a pH less than 7?

The amino group has a positive charge and the carboxylic acid is neutral.

How does the amino group change at pH greater than 7?

The amino group becomes neutral.

What is the significance of chirality in amino acids?

All amino acids except glycine are chiral due to having four different groups attached to the alpha carbon.

What designations are used for L and D amino acids?

L amino acids have the amino group on the left; D amino acids have it on the right.

How are proteins structured?

Proteins are amino acid polymers linked by peptide bonds.

What type of reaction connects amino acids to form polypeptides?

Amination or dehydration synthesis.

What type of reaction is used to break down proteins?

Hydrolysis.

What is the bond formed when amino acids connect called in biochemical terms?

Peptide bond.

What is the first structure category of proteins?

Primary structure.

What defines the primary structure of a protein?

The sequence of amino acids.

What is the secondary structure of proteins primarily composed of?

Hydrogen bonding between amide groups in the polypeptide backbone.

What determines the tertiary structure of proteins?

Intermolecular forces and interactions between side chains.

What term refers to the backbone structure of an amino acid?

The chain of nitrogen, carbon, carbon, except the side chain.

What type of amino acids are reflected in the three-letter and one-letter abbreviations?

Standard amino acids.

How are polypeptides related to proteins?

Polypeptides are chains of amino acids that form proteins.

What category do amino acids fall into based on their side chains?

Nonpolar and polar amino acids.

How does the body use dietary proteins?

The body breaks down proteins into amino acids to synthesize its own proteins.

What is the general consequence of a deficiency in essential amino acids?

Nutritional deficiencies and potential health issues.

How are polar side chains classified?

Into polar acidic, polar basic, and polar neutral categories.

How does the body respond to changes in pH regarding amino acids?

It alters the charge state of the amino and carboxylic groups.

What is the difference between a carboxylic acid and a carboxylate ion?

A carboxylic acid has a proton while a carboxylate ion is deprotonated.

What are dipeptides?

Two amino acids linked together.

How does the primary structure affect protein function?

The sequence of amino acids determines the protein's structure and function.

What is the major component of the protein backbone?

The repeating sequence of nitrogen and carbon atoms.

What reaction involves the formation of a peptide bond?

Amination, or the dehydration synthesis reaction.

What is the term used to describe the non-bonded ends of a protein?

N-terminus and C-terminus.

Why is glycine an exception in chirality?

It has two identical hydrogen atoms attached to its alpha carbon.

What is the effect of replacing an amino acid in a protein?

It can disrupt the protein's function.

What are the visual representations of amino acids needed for?

To memorize their structures, names, and abbreviations.

What classification is based on the presence of functional groups in amino acid side chains?

Polar and nonpolar classifications.

What is a characteristic feature of cyclic amino acids?

The side chain loops back to bond with the amino nitrogen.

What happens to protein structure when intermolecular forces are disrupted?

It may lead to denaturation and loss of function.

What types of forces influence the tertiary structure of proteins?

Hydrogen bonds, ionic interactions, hydrophobic interactions, and van der Waals forces.

What level of protein structure is solely determined by covalent bonds?

Primary structure.

Why is the understanding of amino acids essential in biochemistry?

They are fundamental building blocks of proteins that play crucial roles in biological processes.