Question 1

Which of the following best describes the fundamental structure of an amino acid?

Accepted Answer

A central carbon atom bonded to an amino group, a carboxyl group, a hydrogen atom, and a variable R group.

Question 2

What type of chemical reaction forms a peptide bond between two amino acids?

Accepted Answer

A dehydration reaction

Question 3

Which property of an amino acid is primarily determined by its R group?

Accepted Answer

Its chemical properties such as charge, polarity, and hydrophobicity

Question 4

A mutation causes a single amino acid change in the hemoglobin protein, resulting in sickle cell anemia. Which level of protein structure is directly affected by this mutation?

Accepted Answer

Primary structure

Question 5

Which of the following is NOT a function of proteins in biological systems?

Accepted Answer

Storing genetic information

Question 6

Which bond is responsible for stabilizing the secondary structure of proteins, such as alpha helices and beta sheets?

Accepted Answer

Hydrogen bonds

Question 7

What is the result of denaturation in a protein?

Accepted Answer

The protein loses its higher-level structures and therefore its function.

Question 8

Which of the following best explains why proteins have such a diversity of functions?

Accepted Answer

Proteins have a wide variety of sizes, shapes, and chemical properties due to different amino acid sequences.

Question 9

Which of the following correctly matches a protein function with its example?

Accepted Answer

Transport protein – hemoglobin carrying oxygen

Question 10

A protein is exposed to high heat and extreme pH. What is most likely to happen?

Accepted Answer

The protein will denature, losing its functional shape.

Question 11

Which of the following is true about the directionality of a polypeptide chain?

Accepted Answer

The N-terminus has a free amino group and the C-terminus has a free carboxyl group.

Question 12

Which of the following best describes a quaternary protein structure?

Accepted Answer

The combination of two or more separate polypeptide chains

Question 13

Which equation represents the dehydration reaction that forms a peptide bond between two amino acids?

Accepted Answer

$$\mathrm{Amino\ acid}_1 + \mathrm{Amino\ acid}_2 \rightarrow \mathrm{Dipeptide} + H_2O$$

Question 14

Which of the following amino acids is most likely to be found on the surface of a protein in an aqueous environment?

Accepted Answer

Serine (Ser)

Question 15

If a protein loses its tertiary structure but retains its primary structure, which of the following is most likely to occur?

Accepted Answer

The protein will lose its specific 3D shape and most of its function.

Question 16

Which of the following is a correct statement about peptide bonds?

Accepted Answer

Peptide bonds are formed between the carboxyl group of one amino acid and the amino group of another.

Question 17

Which of the following best explains why a single amino acid change can drastically affect protein function?

Accepted Answer

It alters the protein's primary structure, which can change folding and function.

Question 18

Which of the following is NOT a class of biological organic compounds?

Accepted Answer

Minerals

Question 19

Which of the following interactions is NOT typically involved in stabilizing a protein's tertiary structure?

Accepted Answer

Peptide bonds between R groups

Question 20

A scientist isolates a protein and finds it consists of four polypeptide chains. Which level of protein structure is being described?

Accepted Answer

Quaternary structure

Protein Structure and Function: Study Notes for General Biology

Guida di studio - Domande di pratica

Study guide - Flashcard