Question 1

The genetic material found in all living things is made of building blocks called

Accepted Answer

The genetic material found in all living things is made up of nucleotides, which consist of a sugar molecule, a phosphate group, and a nitrogenous base. Monosaccharides are simple sugars, phospholipids are components of cell membranes, and steroids are a type of lipid with a different structure than nucleotides.

Question 2

Which of the following most commonly represents the shape associated with functional proteins?

Accepted Answer

Functional proteins are characterized by their unique three-dimensional folded structures that allow them to perform their specific biochemical functions. A long linear chain of amino acids (A) does not have the proper structure to form a functional protein. Similarly, individual amino acids that are not covalently joined together (B) cannot form functional proteins. While coils and sheets of joined amino acids (C) can be a part of the protein structure, they do not fully represent the shape of the functional protein. Only three-dimensional folded chains of amino acids (D) fully capture the shape of functional proteins.

Question 3

Which of the following factors explains carbon's prominence in living systems?

Accepted Answer

Carbon-based molecules can form long chains and rings, which allows for diverse structures and functions. This property allows for the vast complexity seen in living systems, including the ability to form proteins, DNA, and other important molecules.

Question 4

Macromolecules are typically formed by repetitively adding small monomers together. Which macromolecule is properly matched with the appropriate monomer?

Accepted Answer

Polypeptides are formed by linking amino acids together through peptide bonds. Nucleic acids, on the other hand, are formed by linking nucleotides together through phosphodiester bonds. Polysaccharides are formed by linking monosaccharides together through glycosidic bonds. Triglycerides are formed by linking three fatty acids to a glycerol molecule.

Question 5

Which of the following are composed of the same monomers?

Accepted Answer

Starch and cellulose are both composed of glucose monomers, while proteins and DNA are composed of amino acids and nucleotides, respectively. RNA and cellulose also have different monomers (ribonucleotides and glucose, respectively). Cholesterol and sucrose are also composed of different monomers (steroids and glucose-fructose, respectively).

Question 6

A disaccharide consists of two

Accepted Answer

A disaccharide is a molecule composed of two monosaccharides (simple sugars) joined by a glycosidic bond. Therefore, the best choice is A.

Question 7

Which of the following is the largest in size?

Accepted Answer

Proteins are typically the largest of the molecules listed, consisting of long chains of amino acids with complex three-dimensional structures. Glucose and nucleotides are much smaller, and a carbon atom is the smallest building block of these larger molecules.

Question 8

A scientist observed a chemical that changes to bright red in the presence of organic compounds containing nitrogen and phosphorus. To test this chemical, a set of test tubes each containing a purified sample of one of the following organic compounds is prepared. The chemical is then added to each tube. Which test tube will always turn bright red?

Accepted Answer

Nucleic acids contain both nitrogen and phosphorus, which react with the chemical to turn it bright red. Proteins also contain nitrogen, but not all proteins contain phosphorus. Carbohydrates and phospholipids do not contain nitrogen or phosphorus.

Question 9

Which of the following statements is true of proteins, carbohydrates, and nucleic acids?

Accepted Answer

Proteins, carbohydrates, and nucleic acids are all built from a common set of monomers. Proteins are made up of amino acids, carbohydrates are made up of monosaccharides, and nucleic acids are made up of nucleotides.

Question 10

One of the symptoms of kidney disease is the presence of proteins in a patient's urine. To quickly test for kidney disease using a urine sample, a doctor might add a chemical that causes a color change when

Accepted Answer

Proteins contain nitrogen, but not phosphorus. Therefore, adding a chemical that reacts with nitrogen would indicate the presence of proteins in the urine and suggest the possibility of kidney disease.

Question 11

Your supervisor provides you with lipids, carbohydrates, proteins, and nucleic acids and asks you to determine their chemical components. Which of the following elements would you NOT expect to find in these items?

Accepted Answer

Iron is not typically found in these macromolecules. Phosphorus is found in nucleic acids (DNA and RNA), hydrogen is found in all four macromolecules, and nitrogen is found in proteins and nucleic acids.

Question 12

Carbon atoms are bound to each other by

Accepted Answer

Carbon atoms are known to form covalent bonds, which involve the sharing of electrons between the atoms. This sharing of electrons allows each atom to fill its outermost electron shell and achieve greater stability.

Question 13

We use soap to clean ourselves better than we could with water alone. Soaps contain phospholipids that are responsible for the cleansing action. Which of the following statements is the most likely explanation for how soaps work?

Accepted Answer

The phospholipid tail attaches to the oily dirt while the phospholipid head interacts with the rinse water and carries the dirt away with it.

Question 14

Molecules with an uneven distribution of charge are described as ________.

Accepted Answer

The answer of Molecules with an uneven distribution of charge...

Question 15

Which of the following could be built solely from glucose molecules?

Accepted Answer

Starch is composed solely of glucose molecules. Fatty acids and oils are composed of carbon, hydrogen, and oxygen molecules, but not solely glucose. DNA is composed of nucleotides, which include a sugar component but also other molecules such as nitrogenous bases and phosphate groups.

Question 16

Nucleotides

Accepted Answer

Nucleotides are the building blocks of nucleic acids like DNA and RNA.

Question 17

In the laboratory you identify protein in a food item that you've tested. Which of the following must the food item also contain?

Accepted Answer

Proteins are composed of chains of amino acids, therefore if a protein is present in the food item, it must also contain amino acids. Glucose, lipids and nucleotides are not directly related to the presence of protein in the food item.

Question 18

An atom that becomes charged due to the gain or loss of an electron is called a(n) ________.

Accepted Answer

The answer of An atom that becomes charged due to...

Question 19

An instrument that identifies chemicals based upon their weights is the ________.

Accepted Answer

The answer of An instrument that identifies chemicals based upon...

Question 20

The positively charged subatomic particle is located in the ________.

Accepted Answer

The answer of The positively charged subatomic particle is located...

Quiz 2: Chemistry of Life