Question 1

Which of the following represents the linkage connecting amino acids in proteins?

Accepted Answer

A

Question 2

Which of the following concerning protein structure is not correct?

Accepted Answer

Helices and sheets are examples of secondary structures in proteins, not tertiary structures. Tertiary structure refers to the overall 3D shape of a single protein molecule, including the arrangement of secondary structures and the position of amino acid side chains.

Question 3

Which of the following statements concerning carbohydrates is $\underline{\text{  not }}$  correct?

Accepted Answer

The acyclic (linear) form of monosaccharides does not predominate in aqueous solutions; rather, the cyclic (ring) forms are more common due to their stability in such environments.

Question 4

Which of the following functional groups is not found in carbohydrates (sugars)?

Accepted Answer

Carboxylic acid is not found in carbohydrates, which typically contain aldehyde or ketone functional groups and multiple alcohol (hydroxyl) groups. Carboxylic acids are found in other biomolecules such as fatty acids and amino acids.

Question 5

How many unique tripeptides can be made from two molecules of the amino acid valine (val)and one molecule of the amino acid alanine (ala)?

Accepted Answer

A tripeptide is made up of three amino acids. In this case, we have two molecules of valine (val) and one molecule of alanine (ala). To find the number of unique tripeptides we can make, we need to use a combination of these amino acids. 
The possible combinations are: 
- val-val-ala 
- val-ala-val 
- ala-val-val 
So there are three possible unique tripeptides that can be made.

Question 6

What is the most prevalent form of the amino acid glycine (R = H)in an aqueous environment at a physiological pH.

Accepted Answer

The answer of What is the most prevalent form of...

Question 7

Which of the following amino-acids is $\underline{\text{  not }}$ chiral?

Accepted Answer

The answer of Which of the following amino-acids is \(\underline{\text{...

Question 8

The glycosidic bonds that form the link between sugars in disaccharides are formed by

Accepted Answer

Glycosidic bonds in disaccharides are formed by a condensation reaction, where two sugar molecules lose water to form a covalent bond between their anomeric carbons. This reaction results in the formation of a new bond with the elimination of a molecule of water.

Question 9

Which of the following functional groups is not found in naturally occurring proteins or their amino acid building blocks?

Accepted Answer

Ketone groups are not found in naturally occurring proteins or their amino acid building blocks. Amino acids have an amine group (-NH2) and a carboxylic acid group (-COOH), which are joined together to form an amide bond (-CONH-) between them. There may also be alcohol groups (-OH) in some amino acids, but ketone groups are not present.

Question 10

The sequence of the amino acids in a protein is termed the ____ structure.

Accepted Answer

The sequence of the amino acids in a protein is called the primary structure. This is the first level of the protein's structure, and it determines the higher levels of organization. The secondary, tertiary, and quaternary structures refer to the arrangement of the polypeptide chain into regular structures such as alpha helices and beta sheets, the overall 3D shape of the protein, and the association of multiple polypeptide chains, respectively.

Question 11

A polypeptide is

Accepted Answer

A polypeptide is formed through a condensation reaction between amino acids, where a water molecule is released. It is not an addition polymer where monomers are added without loss of any molecule like water. Polypeptides are not made up of sugar molecules or nucleic acids.

Question 12

What carbohydrate is the form in which plants store glucose for future use as cellular fuel?

Accepted Answer

Plants store glucose in the form of starch, which serves as a long-term energy storage molecule for the plant. Cellulose is a structural carbohydrate found in the cell walls of plants, glycogen is a similar carbohydrate found in animals, sucrose is a disaccharide made up of glucose and fructose, and fructose is a monosaccharide commonly found in fruit. However, none of these is the primary carbohydrate used for glucose storage in plants.

Question 13

Which of the following statements concerning enzyme chemistry is/are correct?
1)Enzymes are biological catalysts.
2)A reaction occurs when substrate binds the enzyme active site.
3)Enzymes catalyze multiple types of reactions.

Accepted Answer

Statement 1 is correct as enzymes are biological catalysts.
Statement 2 is correct as a reaction occurs when substrate binds the enzyme active site.
Statement 3 is incorrect as enzymes are specific for the type of reaction they can catalyze. Therefore, the correct choice is D, which includes statements 1 and 2 only.

Question 14

Nonpolar amino acid side chains contain substituents made mostly of what atoms?

Accepted Answer

Nonpolar amino acids, such as alanine and valine, have side chains consisting mostly of carbon and hydrogen atoms. This makes them hydrophobic and capable of being buried in the interior of a protein.

Question 15

Which of the following statements concerning polysaccharides is/are correct?
1)Humans do not have enzymes that will break down cellulose.
2)Amylopectin and glycogen are both branched chains of glucose.
3)Amylose starch is a linear polysaccharide.

Accepted Answer

Humans lack the enzyme cellulase to break down cellulose (1). Both amylopectin and glycogen are branched polysaccharides (2). Amylose is a linear polysaccharide (3).

Question 16

Which of the following is not a polysaccharide?

Accepted Answer

Polysaccharides are long chains of monosaccharides, which are simple sugars. Glycogen, cellulose, amylose starch, and amylopectin starch are all examples of polysaccharides. Lactose, on the other hand, is a disaccharide composed of glucose and galactose, not a polysaccharide.

Question 17

Which of the following statements concerning proteins is $\underline{\text{ not  }}$ correct?

Accepted Answer

The last statement is not correct. While nucleic acids (DNA and RNA) contain the instructions for protein synthesis, they are not the building blocks of protein. The building blocks of protein are amino acids.

Question 18

What is the functional group corresponding to a peptide bond?

Accepted Answer

A peptide bond is formed between the carboxyl group (-COOH) of one amino acid and the amino group (-NH2) of another amino acid through a dehydration synthesis reaction to form an amide bond (-CONH-). Therefore, the functional group corresponding to a peptide bond is an amide group.

Question 19

A disaccharide is formed when two monosaccharides are linked by the elimination of a molecule of water and the formation of an ether bond.The newly formed C-O bond linking the monosaccharides is called the ____ bond.

Accepted Answer

The new bond formed between two monosaccharides resulting in the formation of a disaccharide is called a glycosidic bond. Therefore, option E is the correct choice. Aldose and ketose refer to the type of monosaccharide structure, while glycogen is a polysaccharide. Cyclic refers to the ring structure of a monosaccharide.

Question 20

Which statement concerning the twenty different $\alpha$-amino acids widely found in nature is true?

Accepted Answer

The statement that is true is that these F1F1F1S1F1F1F10-amino acids differ in the R groups attached to the F1F1F1S1F1F1F10-carbon. The other options are not accurate: A) This statement is incorrect, as all amino acids have the same basic backbone of carbons. B) This statement is only partially correct, as all amino acids have one amino group, but they also have a carboxylic acid group. C) This statement is only partially correct, as all amino acids have one carboxylic acid group, but they also have an amino group. E) This statement is incorrect, as some of these amino acids, such as phenylalanine, are aromatic compounds.

Quiz 25: Biochemistry

Which of the following represents the linkage connecting amino acids in proteins?

Which of the following concerning protein structure is not correct?

Which of the following statements concerning carbohydrates is $\underline{\text{ not }}$ correct?

Which of the following functional groups is not found in carbohydrates (sugars) ?

How many unique tripeptides can be made from two molecules of the amino acid valine (val) and one molecule of the amino acid alanine (ala) ?

What is the most prevalent form of the amino acid glycine (R = H) in an aqueous environment at a physiological pH.

Which of the following amino-acids is $\underline{\text{ not }}$ chiral?

The glycosidic bonds that form the link between sugars in disaccharides are formed by

Which of the following functional groups is not found in naturally occurring proteins or their amino acid building blocks?

The sequence of the amino acids in a protein is termed the ____ structure.

A polypeptide is

What carbohydrate is the form in which plants store glucose for future use as cellular fuel?

Which of the following statements concerning enzyme chemistry is/are correct? 1) Enzymes are biological catalysts. 2) A reaction occurs when substrate binds the enzyme active site. 3) Enzymes catalyze multiple types of reactions.

Nonpolar amino acid side chains contain substituents made mostly of what atoms?

Which of the following statements concerning polysaccharides is/are correct? 1) Humans do not have enzymes that will break down cellulose. 2) Amylopectin and glycogen are both branched chains of glucose. 3) Amylose starch is a linear polysaccharide.

Which of the following is not a polysaccharide?

Which of the following statements concerning proteins is $\underline{\text{ not }}$ correct?

What is the functional group corresponding to a peptide bond?

A disaccharide is formed when two monosaccharides are linked by the elimination of a molecule of water and the formation of an ether bond.The newly formed C-O bond linking the monosaccharides is called the ____ bond.

Which statement concerning the twenty different $\alpha$ -amino acids widely found in nature is true?

Quiz 25: Biochemistry

Which of the following represents the linkage connecting amino acids in proteins?

Which of the following concerning protein structure is not correct?

Which of the following statements concerning carbohydrates is not ‾\underline{\text{ not }} not ​ correct?

Which of the following functional groups is not found in carbohydrates (sugars) ?

How many unique tripeptides can be made from two molecules of the amino acid valine (val) and one molecule of the amino acid alanine (ala) ?

What is the most prevalent form of the amino acid glycine (R = H) in an aqueous environment at a physiological pH.

Which of the following amino-acids is not ‾\underline{\text{ not }} not ​ chiral?

The glycosidic bonds that form the link between sugars in disaccharides are formed by

Which of the following functional groups is not found in naturally occurring proteins or their amino acid building blocks?

The sequence of the amino acids in a protein is termed the ____ structure.

A polypeptide is

What carbohydrate is the form in which plants store glucose for future use as cellular fuel?

Which of the following statements concerning enzyme chemistry is/are correct? 1) Enzymes are biological catalysts. 2) A reaction occurs when substrate binds the enzyme active site. 3) Enzymes catalyze multiple types of reactions.

Nonpolar amino acid side chains contain substituents made mostly of what atoms?

Which of the following statements concerning polysaccharides is/are correct? 1) Humans do not have enzymes that will break down cellulose. 2) Amylopectin and glycogen are both branched chains of glucose. 3) Amylose starch is a linear polysaccharide.

Which of the following is not a polysaccharide?

Which of the following statements concerning proteins is not ‾\underline{\text{ not }} not ​ correct?

What is the functional group corresponding to a peptide bond?

A disaccharide is formed when two monosaccharides are linked by the elimination of a molecule of water and the formation of an ether bond.The newly formed C-O bond linking the monosaccharides is called the ____ bond.

Which statement concerning the twenty different α\alphaα -amino acids widely found in nature is true?

Which of the following statements concerning carbohydrates is $\underline{\text{ not }}$ correct?

Which of the following amino-acids is $\underline{\text{ not }}$ chiral?

Which of the following statements concerning proteins is $\underline{\text{ not }}$ correct?

Which statement concerning the twenty different $\alpha$ -amino acids widely found in nature is true?