Question 1

Each of the following is a component of an amino acid except one. Which one is the exception? A) Carbon dioxide group (CO₂) B) Amino group (-NH₃⁺) C) Carboxyl group (-COO^-) D) Side chain (R group)

Accepted Answer

Carbon dioxide is not a component of an amino acid. It is a product from the oxidation of glucose. The amino group, the carboxyl group, and the R group form the general structure of an amino acid. Proteins can consist of as few as 50 to as many as millions of amino acid monomers.

Question 2

Biochemists organize the variety in chemical structure by classifying molecules into functional groups. A functional group is a group of atoms that gives a family of molecules its characteristic chemical and physical properties.

A) Both statements are true.
B) Both statements are false.
C) The first statement is true; the second is false.
D) The first statement is false; the second is true.

Both statements are true.

Accepted Answer

Molecules that have similar functional groups have similar properties. In addition to carbon, the combination of different atoms like hydrogen (H), oxygen (O), nitrogen (N), sulfur (S), and phosphorus (P) form biomolecules that provide great variety in chemical structure, properties and reactivity in biological systems.

Question 3

The biological function that plants use to make the carbohydrate animals can use for energy and oxygen is called:&#10;A) oxidation-reduction.&#10;B) condensation.&#10;C) hydrolysis.&#10;D) photosynthesis.

Accepted Answer

Photosynthesis is the biological function that plants use to make the carbohydrate C₆H₁₂O₆(glucose), a carbohydrate that animals can use for energy and storage. Oxidation-reduction, condensation, and hydrolysis are chemical reactions that can convert functional groups into other functional groups.

Question 4

Each of the following is a major area of biochemistry except one. Which one is the exception?&#10;A) Structure&#10;B) Function&#10;C) Metabolism&#10;D) Information

Accepted Answer

Function is not a major area of biochemistry. The three major areas of biochemistry, the study of life at the molecular level, are structure, metabolism, and information.

Question 5

During the Krebs cycle complete aerobic oxidation of glucose (C₆H₁₂O₆) produces each of the following except one. Which one is the exception? A) CO₂ B) H₂O C) ATP D) Amino acids

Accepted Answer

During the Krebs cycle, also known as the TCA cycle, complete aerobic oxidation of glucose produces carbon dioxide (CO₂), water (H₂O), and adenosine triphosphate (ATP). Glucose is a carbohydrate, whereas amino acids are broken down from proteins. Although amino acids are involved in the Krebs cycle, the production of CO₂, water, and ATP from glucose differs from the production of amino acids from protein. Note that lipids are also catabolized during the Krebs cycle. Ultimately, the end products of catabolism of all nutrients are CO₂, H₂O, and ammonia (NH₃).

Question 6

The biomolecules necessary for life are based on carbon because carbon has the ability to form glycosidic bonds to itself and many other atoms.&#10;A) Both the statement and the reason are correct and related.&#10;B) Both the statement and the reason are correct, but are not related.&#10;C) The statement is correct, but the reason is not correct.&#10;D) The statement is not correct, but the reason is correct.&#10;E) Neither the statement nor the reason is correct.

Accepted Answer

Biomolecules are based on carbon because carbon has the ability to form stable covalent bonds with itself and with many other atoms. A covalent bond forms when electrons are shared equally between two nonmetals. A glycosidic bond forms when a disaccharide is formed from two monosaccharides reacting together.

Question 7

Which function has the least priority for protein?&#10;A) Energy storage&#10;B) Providing structure&#10;C) Muscle contraction&#10;D) Catalyzing reactions&#10;E) Regulating metabolism

Accepted Answer

Energy storage is a primary function of carbohydrates and fats. Although protein can produce and store energy, this is not a primary role and takes away from other vital roles. The remaining selections are priority functions of protein. Note that catalyzing a reaction involves breaking down of components, such as when more complex molecules are catabolized into smaller molecules.

Question 8

Fatty acids are structural components that are present in more complex lips, such as triglycerides (TGs). Also referred to as triacylglycerols, TGs synthesize fatty acids.&#10;A) Both statements are true.&#10;B) Both statements are false.&#10;C) The first statement is true; the second is false.&#10;D) The first statement is false; the second is true.

Accepted Answer

Triglycerides, also referred to as triacylglycerols, do not synthesize fatty acids. TGs are the storage forms of fatty acids (Fas) and are considered the metabolic fuel for cells stored in adipose (fat) tissue.

Question 9

Each of the following exemplifies glycosidic bonding reactions except one. Which one is the exception?&#10;A) A condensation reaction can unite two glucose monomers into maltose.&#10;B) Maltose is a disaccharide that results from degradation of starch.&#10;C) Maltose is used in brewing and in alcoholic beverages.&#10;D) The disaccharide lactose is formed from the two monosaccharides: galactose and glucose.&#10;E) When fructose and sucrose combine, glucose is formed.

Accepted Answer

The monosaccharides glucose and fructose react together to form the disaccharide sucrose. Sucrose is table sugar and is one of the sweetest of the carbohydrates.

Question 10

Enzymes perform all the chemical reactions of metabolism involving degradation and biosynthesis of biomolecules required for life. Proteases, amylases, and lipases are coenzymes.&#10;A) Both statements are true.&#10;B) Both statements are false.&#10;C) The first statement is true; the second is false.&#10;D) The first statement is false; the second is true.

Accepted Answer

Proteases, amylases, and lipases are enzymes that begin the process of digesting dietary proteins, carbohydrates, and lipids, respectively.

Question 11

Each of the following is true of proteins except one. Which one is the exception?&#10;A) Proteins are composed of building blocks called amino acids.&#10;B) The classification of the 20 common amino acids is based on the structure of their amino group.&#10;C) The general structure of an amino acid varies considerably.&#10;D) Amino acids polymerize to form long chains called polypeptides.&#10;E) Amino acids contain strong covalent peptide bonds.

Accepted Answer

The answer of Each of the following is true of...

Question 12

Antioxidants like vitamins C and E are added to unsaturated fats because antioxidants prevent rancidity associated with the oxidation during preparation of vegetable oils and margarines.&#10;A) Both the statement and the reason are correct and related.&#10;B) Both the statement and the reason are correct but are not related.&#10;C) The statement is correct, but the reason is not correct.&#10;D) The statement is not correct, but the reason is correct.&#10;E) Neither the statement nor the reason is correct.

Accepted Answer

The answer of Antioxidants like vitamins C and E are...

Question 13

In metabolism, energy is extracted from glucose (C₆H₁₂O₆) and converted to carbon dioxide (CO₂) by which chemical reaction? A) Oxidation B) Reduction C) Hydrolysis D) Condensation

Accepted Answer

The answer of In metabolism, energy is extracted from glucose...

Question 14

Carbohydrates are classified as each of the following except one. Which one is the exception?&#10;A) Monosaccharides&#10;B) Disaccharides&#10;C) Polysaccharides&#10;D) Triglycerides

Accepted Answer

The answer of Carbohydrates are classified as each of the...

Question 15

In general, a condensation reaction creates a new molecule by:&#10;A) breaking a larger molecule into two smaller molecules.&#10;B) forming an ionic bond between a metal and a nonmetal ion.&#10;C) forming a bond between two smaller molecules.&#10;D) sharing two electrons between two nonmetals.

Accepted Answer

The answer of In general, a condensation reaction creates a...

Question 16

Coenzymes are protein organic substances that assist enzymes in converting the substrate into a carbohydrate. Many vitamins are converted into biologically active coenzymes.&#10;A) Both statements are true.&#10;B) Both statements are false.&#10;C) The first statement is true; the second is false.&#10;D) The first statement is false; the second is true.

Accepted Answer

The answer of Coenzymes are protein organic substances that assist...

Question 17

Saturated fatty acids are alkenes that contain one or more C=C (double) bond. Unsaturated fatty acids, contain only one C=C bond.&#10;A) Both statements are true.&#10;B) Both statements are false.&#10;C) The first statement is true; the second is false.&#10;D) The first statement is false; the second is true.

Accepted Answer

The answer of Saturated fatty acids are alkenes that contain...

Question 18

A biomolecule is a substance required by the body that must be supplied by an outside source. During metabolism, energy can be extracted from dietary carbohydrates, proteins, lipids and can be used to create biomolecules required for life.

A) Both statements are true.
B) Both statements are false.
C) The first statement is true; the second is false.
D) The first statement is false; the second is true.

Accepted Answer

The answer of A biomolecule is a substance required by...

Question 19

Cholesterol is the most abundant lipoprotein and is important to biological membranes. Cholesterol is also the precursor of steroid hormones, bile acids, and the lipid-soluble vitamin D.&#10;A) Both statements are true.&#10;B) Both statements are false.&#10;C) The first statement is true; the second is false.&#10;D) The first statement is false; the second is true.

Accepted Answer

The answer of Cholesterol is the most abundant lipoprotein and...

Question 20

Each of the following is a characteristic or function of lipids except one. Which one is the exception?&#10;A) Lipids are involved in energy metabolism and storage.&#10;B) Lipids provide insulation and protection.&#10;C) Lipids acts as hormones that regulate the body.&#10;D) Lipids are hydrophilic.

Accepted Answer

The answer of Each of the following is a characteristic...

Question 21

When the body's stores of energy are depleted, the pancreas becomes involved because gluconeogenesis can convert pyruvate into glucose for energy.&#10;A) Both the statement and the reason are correct and related.&#10;B) Both the statement and the reason are correct but are not related.&#10;C) The statement is correct, but the reason is not correct.&#10;D) The statement is not correct, but the reason is correct.&#10;E) Neither the statement nor the reason is correct.

Accepted Answer

The answer of When the body's stores of energy are...

Question 22

Each of the following is true of lipids except one. Which one is the exception?&#10;A) The catabolism of lipids is a major source of energy for the body.&#10;B) Lipids can by oxidized to produce more energy than carbohydrates or proteins.&#10;C) The hydrous nature of lipids make them retain water.&#10;D) Lipids can be stored in adipose tissue in unlimited amounts.

Accepted Answer

The answer of Each of the following is true of...

Deck 2: Concepts in Biochemistry