Question 1

Which of these is a basic amino acid?
A) Valine
B) Aspartic acid
C) Histidine
D) Tryptophan
E) Serine

Accepted Answer

Histidine is a basic amino acid because it contains an amino group and a nitrogen-containing ring structure, which allows it to act as a base and accept a proton. Valine, Aspartic acid, Tryptophan, and Serine are non-basic amino acids.

Question 2

Which of these molecules link together to form proteins?
A) Vitamins
B) Amino acids
C) Monosaccharides
D) Fatty acids
E) Triglycerides

Accepted Answer

Proteins are formed by linking amino acids together through peptide bonds. Vitamins, monosaccharides, fatty acids, and triglycerides are not involved in protein formation.

Question 3

Which of these statements about carbohydrates is correct ?
A) Carbohydrates contain both a carboxyl and an amine group.
B) Carbohydrates contain a phosphate backbone with sugar groups.
C) Carbohydrates release more energy per gram than any other biomolecule.
D) Carbohydrates are polyhydroxy aldehydes or ketones, or their derivatives.
E) Carbohydrates are formed when a carboxylic acid reacts with glycerol in an acidic environment.

Accepted Answer

Carbohydrates are polyhydroxy aldehydes or ketones, or their derivatives. They do not contain carboxyl or amine groups and do not have a phosphate backbone. While carbohydrates do release energy when metabolized, they do not release more energy per gram than lipids or fats. They are not formed by the reaction of a carboxylic acid and glycerol.

Question 4

Which of these is an acidic amino acid?
A) Isoleucine
B) Aspartic acid
C) Histidine
D) Threonine
E) Alanine

Accepted Answer

Aspartic acid is an acidic amino acid due to the presence of carboxylic acid group in its side chain.

Question 5

Which of these determines the primary structure of a protein?
A) Sequence of amino acids
B) Number of hydrogen bonds
C) Ratio of the number of acidic amino acids to the number of basic amino acids
D) Polarity of the R groups attached to the amino acids
E) Number of alpha helices and pleated sheets along the axis of the protein

Accepted Answer

The primary structure of a protein is determined by the linear sequence of amino acids that make up the protein chain. This sequence is determined by the genetic code encoded in the DNA of an organism. The specific sequence of amino acids ultimately determines the unique three-dimensional structure and resulting function of the protein.

Question 6

Which of these determines the secondary structure of a protein?
A) Sequence of amino acids
B) Ratio of the number of acidic amino acids to the number of basic amino acids
C) Number of carbon bonds in the chain of amino acids
D) Alpha helices and pleated sheets along the axis of the protein
E) Distance between amino acids

Accepted Answer

The secondary structure of a protein is determined by the arrangement of amino acids into alpha helices and pleated sheets along the axis of the protein. The sequence of amino acids determines the primary structure, while the ratio of acidic to basic amino acids and number of carbon bonds do not play a significant role in determining the secondary structure. The distance between amino acids can affect the tertiary structure of a protein, but not the secondary structure.

Question 7

Classify this structure. ​ 
A) Dipeptide
B) Fatty acid
C) Polypeptide
D) Protein
E) Triglyceride

Accepted Answer

The answer of Classify this structure. ​ 
A) Dipeptide
B) Fatty...

Question 8

Which of these is/are polysaccharide(s)?
I. Glucose
II. Cellulose
III. Fructose
IV. Starch
A) I only
B) II only
C) II and III
D) I and II
E) II and IV

Accepted Answer

Cellulose and starch are polysaccharides, which are long chains of monosaccharide units. Glucose and fructose are monosaccharides, not polysaccharides.

Question 9

Classify this structure. ​ 
A) Polysaccharide
B) Amino acid
C) Fatty acid
D) Protein
E) Triglyceride

Accepted Answer

The answer of Classify this structure. ​ 
A) Polysaccharide
B) Amino...

Question 10

Amino acids are linked together by _____ to form proteins.
A) disulfide linkages
B) hydrogen bonds
C) alpha linkages
D) hydrophobic interactions
E) peptide bonds

Accepted Answer

Amino acids are linked together by peptide bonds to form proteins. Disulfide linkages, hydrogen bonds, and hydrophobic interactions play important roles in protein structure but are not involved in the formation of peptide bonds between amino acids. Alpha linkages are not a type of bond involved in the structure of proteins.

Question 11

Which of these is /are  not a monosaccharide(s)?
I. Glucose
II. Fructose
III. Sucrose
A) I only
B) III only
C) II and III
D) I and II
E) I and III

Accepted Answer

Sucrose is not a monosaccharide; it is a disaccharide composed of glucose and fructose. Glucose and fructose are both monosaccharides.

Question 12

A long chain of more than 50 amino acids is known as _____.
A) a polysaccharide
B) a polyamide
C) a polypeptide
D) a protein
E) a  polyamine

Accepted Answer

A long chain of more than 50 amino acids is typically referred to as a protein. Polypeptides are shorter chains of amino acids, and when they fold into a functional form, they are considered proteins.

Question 13

Which of these structures is an amino acid?
A) 
B) 
C) 
D) 
E)

Accepted Answer

The answer of Which of these structures is an amino...

Question 14

Which of these is not a property of glucose?
A) It is easily oxidized.
B) It is soluble in water.
C) It releases more energy per gram than lipids.
D) It undergoes spontaneous intermolecular cyclization.
E) It stores energy in a form that is readily transported.

Accepted Answer

Glucose actually releases less energy per gram than lipids, making lipids a better storage molecule for long-term energy.

Question 15

Which of these property/ properties is /are true for cellulose but not for starch?
I. It consists of a long chain of glucose molecules.
II. Its monosaccharide units are connected by beta linkages.
III. The neighboring monosaccharides form hydrogen bonds.
IV. Its polysaccharides are   easily broken down by enzymes in the body.
A) II only
B) I and III
C) II and III
D) III and IV
E) II, III, and IV

Accepted Answer

Cellulose and starch both consist of a long chain of glucose molecules (property I), but cellulose differs from starch in that its monosaccharide units are connected by beta linkages (property II), whereas starch has alpha linkages. Additionally, the neighboring monosaccharides in cellulose form hydrogen bonds (property III), which provides the rigid structure important for cell walls, whereas starch does not have such a structure. Finally, cellulose is not easily broken down by enzymes in the body, whereas starch is (property IV).

Question 16

Which of these is not an amino acid?
A) Valine
B) Aspartic acid
C) Histidine
D) Oleic acid
E) Serine

Accepted Answer

Oleic acid is a fatty acid, not an amino acid. The other choices (Valine, Aspartic acid, Histidine, Serine) are all amino acids.

Question 17

Classify this structure. ​ 
A) Dipeptide
B) Fatty acid
C) Polypeptide
D) Protein
E) Triglyceride

Accepted Answer

The answer of Classify this structure. ​ 
A) Dipeptide
B) Fatty...

Question 18

Which of these property/ properties is /are true for starch but not for cellulose?
I. It consists of a long chain of glucose molecules.
II. Its monosaccharide units are connected by beta linkages.
III. The neighboring monosaccharides form hydrogen bonds.
IV. Its polysaccharides are easily broken down by enzymes in the body.
A) IV only
B) I and III
C) II and III
D) III and IV
E) II, III, and IV

Accepted Answer

Starch and cellulose both consist of long chains of glucose molecules and have neighboring monosaccharides that form hydrogen bonds. The key difference is that in starch, the glucose units are connected by alpha linkages, making it easily digestible by enzymes in the human body, whereas cellulose has beta linkages, which human enzymes cannot break down.

Question 19

All amino acids contain which functional group?
A) Carboxylic acid
B) Alcohol
C) Alkene
D) Amide
E) Alkyne

Accepted Answer

All amino acids contain a carboxylic acid functional group (-COOH) as well as an amino group (-NH2), which together form an amide bond (-CONH-) in the middle of the molecule.

Question 20

How many different amino acids are there in humans?
A) 18
B) 19
C) 20
D) 21
E) 22

Accepted Answer

There are 20 different amino acids that are commonly found in proteins in humans. These amino acids differ in their side chains, which gives each one unique properties and functions.

Quiz 16: Biochemistry and Biotechnology

Which of these is a basic amino acid?

Which of these molecules link together to form proteins?

Which of these statements about carbohydrates is correct ?

Which of these is an acidic amino acid?

Which of these determines the primary structure of a protein?

Which of these determines the secondary structure of a protein?

Classify this structure.

Which of these is/are polysaccharide(s) ? I. Glucose II. Cellulose III. Fructose IV. Starch

Classify this structure.

Amino acids are linked together by _____ to form proteins.

Which of these is /are not a monosaccharide(s) ? I. Glucose II. Fructose III. Sucrose

A long chain of more than 50 amino acids is known as _____.

Which of these structures is an amino acid?

Which of these is not a property of glucose?

Which of these is not an amino acid?

Classify this structure.

All amino acids contain which functional group?

How many different amino acids are there in humans?

Quiz 16: Biochemistry and Biotechnology

Which of these is a basic amino acid?

Which of these molecules link together to form proteins?

Which of these statements about carbohydrates is correct ?

Which of these is an acidic amino acid?

Which of these determines the primary structure of a protein?

Which of these determines the secondary structure of a protein?

Classify this structure. ​

Which of these is/are polysaccharide(s) ? I. Glucose II. Cellulose III. Fructose IV. Starch

Classify this structure. ​

Amino acids are linked together by _____ to form proteins.

Which of these is /are not a monosaccharide(s) ? I. Glucose II. Fructose III. Sucrose

A long chain of more than 50 amino acids is known as _____.

Which of these structures is an amino acid?

Which of these is not a property of glucose?

Which of these is not an amino acid?

Classify this structure. ​

All amino acids contain which functional group?

How many different amino acids are there in humans?

Classify this structure.

Classify this structure.

Classify this structure.