Proteins and Amino Acids

Which of the following best describes the role of mRNA in protein synthesis?

Lipids, primarily present as triglycerides, directly facilitate the rapid transport of ions across cellular membranes.

Describe how the structural properties of phospholipids contribute to the selective permeability of the cell membrane.

Enzymes, which are a class of ______, catalyze biochemical reactions within cells, increasing the rate at which these reactions occur without being consumed in the process.

Match each type of RNA with its primary function in protein synthesis:

If a cell's ability to synthesize proteins is severely compromised, which of the following cellular processes would be most directly affected?

How do transport proteins facilitate the movement of molecules across cell membranes?

Explain how the dual nature of phospholipids enables them to form and maintain the structure of cell membranes.

How does an acidic environment affect the charge of amino acids?

What characterizes the isoelectric point (pI) of an amino acid or protein?

Enzymes are consumed during the chemical reactions they catalyze.

Name the protein that provides strength to connective tissues, tendons, and bones.

__________ are specialized proteins produced by the immune system to neutralize foreign invaders.

Match each type of protein with its primary function:

What is the primary role of receptor proteins?

Which type of protein is embedded in the cell's lipid bilayer and involved in transport and signal reception?

Ferritin, a storage protein, is primarily involved in storing glucose in the liver.

Name the transport protein that carries oxygen in red blood cells.

__________ are proteins that regulate the expression of specific genes, influencing when and where these genes are activated or repressed.

Match each motor protein with its primary function:

Insulin is an example of which type of protein?

Which of the following is a function of gene regulatory proteins?

Motor proteins facilitate movement by converting mechanical energy into chemical energy.

How does the relatively low percentage of DNA in a cell relate to its function and location?

Proteins are uniform in structure and function across all cell types due to their shared amino acid building blocks.

Describe how the unique 'R group' of an amino acid contributes to the overall structure and function of a protein.

Enzymes catalyze biochemical reactions by lowering the energy ______ required for the reactions to occur.

Match the class of protein with its biological role:

Which of the following is a critical function of proteins in the immune system?

Which of the following statements accurately describes the behavior of a carboxylic acid group (-COOH) in an aqueous solution as the pH increases from acidic to basic?

An amino acid with a non-ionizable side chain will be most soluble in water at its isoelectric point (pI).

The sequence of amino acids in a protein does not impact its three-dimensional structure or function.

Explain how the presence of an ionizable side chain on an amino acid affects the shape of its titration curve, compared to an amino acid with a non-ionizable side chain.

Explain how proteins facilitate metabolic control within the body.

The pH at which the molecule carries no electrical charge is called the ______.

The bond formed between the carboxyl group of one amino acid and the amine group of another is known as a ______ bond.

What distinguishes the 20 different amino acids from one another?

Match the following descriptions to the correct form of amino acid at the given pH:

DNA constitutes a larger percentage of cellular mass than proteins.

For an amino acid with an ionizable side chain, what is the correct method to calculate the isoelectric point (pI)?

Describe the role of active sites in enzyme function and how they relate to amino acid interactions.

Amino acids are effective buffers at pH values far from their pKa values.

Explain why an amino acid does not migrate in an electric field at its isoelectric point (pI).

The process by which amino acids are linked together to form a long chain is called ______.

What is the primary reason fats serve as a long-term energy source compared to carbohydrates?

Amino acids with uncharged side chains, such as glycine, have two pKa values because of the presence of the α-______ group and the α-______ group.

Which statement accurately describes the relationship between pKa and the tendency of a group to be protonated?

What are the four main macromolecules?

Which characteristic of amino acid side chains is most directly responsible for the diversity in protein structure and function?

All proteins within a cell are synthesized using different sets of amino acids, depending on the protein’s specific function.

Describe how the amphiprotic nature of amino acids contributes to their biological function.

The formation of a disulfide bridge between two ______ residues in a polypeptide chain contributes to protein stability.

Match the amino acid with its classification based on its R substituent.

Given that pH = -log[H3O+], what happens to the pKa value as the acidity constant (Ka) increases?

Mutations that alter the amino acid sequence of a protein always lead to a loss of function.

Describe the roles proteins play in maintaining cellular homeostasis and responding to environmental changes.

In an acidic environment with a pH much lower than its pKa, an amino acid will be predominantly in its ______ form.

Two proteins, protein A and protein B, have similar molecular weights but very different functions within the cell. What is the most likely reason for their functional divergence?

The sequence of amino acids in a protein is determined solely by environmental factors present during protein translation.

Explain why glycine is unique among the 20 common amino acids.

Based on the approximate composition of a cell, if a cell has a dry weight of 100g, the weight of the proteins would be approximately ______g.

Considering protein folding and function, what is the primary significance of the hydrophobic effect?

Match the protein with its primary function in living tissues: