Which of the following is/are true regarding proteins? Select all that apply.
(NCLEX/HESI/TEAS)
a. Proteins are made of amino acids.
b. Proteins can have higher-order structure.
c. Proteins are made by hydrolysis reactions.
d. Peptides are large proteins.
e. A protein's secondary structure is independent of the primary structure.
f. If the protein's primary structure is altered, it will not impact the protein's tertiary
structure.

Verified step by step guidance

1. Review the basic building blocks of proteins, which are amino acids, and understand how they link together to form proteins.
2. Understand the concept of protein structure, including primary, secondary, tertiary, and quaternary structures, and how they relate to each other.
3. Examine the process of protein synthesis, focusing on the role of dehydration synthesis (condensation reactions) rather than hydrolysis.
4. Clarify the difference between peptides and proteins, noting that peptides are smaller chains of amino acids, while proteins are larger and more complex.
5. Analyze how changes in the primary structure (amino acid sequence) can affect the higher-order structures, such as secondary and tertiary structures, due to alterations in folding and interactions.

Key Concepts

Protein Structure

Proteins are complex molecules composed of long chains of amino acids, which fold into specific three-dimensional shapes. The structure of a protein is categorized into four levels: primary (sequence of amino acids), secondary (local folding patterns like alpha-helices and beta-sheets), tertiary (overall 3D shape), and quaternary (assembly of multiple polypeptide chains). Understanding these levels is crucial for grasping how proteins function in biological systems.

Amino Acids and Peptides

Amino acids are the building blocks of proteins, linked together by peptide bonds to form peptides and proteins. Peptides are shorter chains of amino acids, while proteins are typically longer and more complex. The distinction between peptides and proteins is important, as it relates to their size, structure, and function in biological processes.

Protein Folding and Function

The function of a protein is heavily dependent on its structure, which is determined by the sequence of amino acids. Changes in the primary structure can lead to alterations in the secondary and tertiary structures, potentially affecting the protein's functionality. This relationship underscores the importance of proper folding and the impact of mutations or modifications on protein activity.