MAP Chapter 2

A fatty acid that contains two or more double covalent bonds is said to be polyunsaturated. carboxylated. hydrogenated. saturated. monounsaturated.

polyunsaturated

Cortisol is a type of lipid hormone. Which type of lipid would cortisol be classified as? triglyceride steroid phospholipid

steroid

Isotopes of an element differ in the number of electron clouds. neutrons in the nucleus. electrons in energy shells. protons in the nucleus. electrons in the nucleus.

neutrons in the nucleus

Which one of the following selections represents the pH of the WEAKEST acid? 1.3 3.2 6.7 12.0

6.7

To maintain homeostasis in the human body, the normal pH range of the blood must remain at __________. 7.35-7.45 6.80-7.80 7.0 6.80-7.20

7.35-7.45

A molecule of water (H2O) is formed by what type of bond? polar covalent bonds weak bonds nonpolar covalent bonds ionic covalent bonds

polar covalent bonds

The most abundant high-energy compound in cells is DNA. adenosine diphosphate. adenosine triphosphate. adenosine monophosphate. RNA.

adenosine triphosphate.

A side chain on an amino acid is sometimes called a polypeptide chain. an R group. an isozyme. nucleic acid. fibrous or globular.

an R group

A solute that dissociates to release hydrogen ions and causes a decrease in pH is __________. an acid water a base a salt

an acid

Which of the following is a solute that releases hydrogen ions in solution and lowers the pH of that solution? a salt a buffer a base an acid

an acid

A(n) ________ removes hydrogen ions and a(n) ________ releases hydrogen ions. base; acid molecule; acid element; compound acid; base compound; element

base; acid

The most important metabolic fuel molecule in the body is vitamins. caffeine. protein. glucose. sucrose.

glucose

A polysaccharide that is formed in liver and muscle cells to store glucose is sucrose. fructose. lactose. cellulose. glycogen.

glycogen

Carbon atoms have four valence electrons. Are they likely to react with other atoms, and why or why not? Yes, because they can become more stable by doing so. Yes, but only with other stable atoms. No, because they do not have enough valence electrons. No, because they have an even number of valence electrons so they are already stable.

Yes, because they can become more stable by doing so.

The purines found in DNA are ________ and guanine. adenine thymine uracil cytosine niacin

adenine

An atom of oxygen has an atomic number of 8 and a mass number of 18. How many of each type of subatomic particle does it contain? 8 protons, 8 neutrons, and 8 electrons 8 protons, 8 electrons, and 10 neutrons 26 total subatomic particles The atomic number and the mass number do not provide enough information to determine how many of each subatomic particle is present.

8 protons, 8 electrons, and 10 neutrons

Which subatomic particles contribute to an atom's mass number but not its atomic number? electrons protons None of them—atomic number and atomic mass number are essentially the same thing. neutrons

neutrons

Formation of hydrogen bonds requires hydrogen atoms and what else? ionic bonds oxygen polar covalent bonds water

polar covalent bonds

Fructose is found in male reproductive fluids. an isomer of glucose. a carbohydrate. a hexose. All of the answers are correct.

All of the answers are correct

In a covalent bond, An atom loses electrons to another to gain stability. Adjacent atoms share a single electron. An atom gains one or more electrons from another atom to gain stability. Atoms share one or more pairs of electrons.

Atoms share one or more pairs of electrons.

Water molecules are formed by __________. Hydrogen bonds nonpolar covalent bonds ionic bonds polar covalent bonds

polar covalent bonds

Calcium's atomic number is 20. It forms ions with 18 electrons. What is the electrical charge of a calcium ion? +1 -1 +2 -2

+2

Of the following choices, the pH of the least acidic solution is 12.0. 6.0. 4.5. 1.0. 2.3.

12.0

If an isotope of oxygen has 8 protons, 10 neutrons, and 8 electrons, its mass number is 26. 8. 18. 16. 12.

18

Oxygen (atomic number 8) requires how many additional electrons to fill its outer electron shell? 6 1 4 2 8

2

The innermost electron shell in an atom holds up to ________ electrons. 4 2 6 1 8

2

Baby Sean has cystic fibrosis, which causes thick mucus secretions that can block ducts like the pancreatic duct, leading to insufficient enzymes in the small intestine. Why are these enzymes important? There are no consequences because there are other enzymes available to catalyze the decomposition reactions. Digestive enzymes catalyze decomposition reactions of complex food molecules into absorbable fragments; without its enzyme, a substrate cannot be degraded. Digestive enzymes are protein molecules that are required to transport food molecules across the intestinal walls for efficient absorption of nutrients. Digestive enzymes catalyze dehydration synthesis reactions that generate important macromolecules like polysaccharides.

Digestive enzymes catalyze decomposition reactions of complex food molecules into absorbable fragments; without its enzyme, a substrate cannot be degraded.

Which of the following statements concerning enzymes is FALSE? Enzymes function as biological catalysts. Enzymes are proteins. Enzymes are consumed during a reaction. Enzymes lower the activation energy of a reaction.

Enzymes are consumed during a reaction.

Which of the following statements about hydrogen bonds is false? Hydrogen bonds can form between neighboring molecules. Hydrogen bonds can occur within a single molecule. Hydrogen bonds are responsible for many of the properties of water. Hydrogen bonds are important for holding large molecules together. Hydrogen bonds are strong attractive forces between hydrogen atoms and negatively charged atoms.

Hydrogen bonds are strong attractive forces between hydrogen atoms and negatively charged atoms.

How do ions form ionic bonds? Two atoms come together to share their electrons. Ions of opposite electrical charges are attracted to each other to balance the charges. Ions of the same type are drawn together because they are attracted to their own kind. One atom swaps all of its negative electrons for all of the other atom's positive protons.

Ions of opposite electrical charges are attracted to each other to balance the charges.

Which of the following statements about water is false? It is responsible for much of the mass of the human body. It has a relatively low heat capacity. It contains hydrogen bonds. It can dissolve many substances. It is composed of polar molecules.

It has a relatively low heat capacity

An important buffer in body fluids is NaHCO3. NaCl. NaOH. HCl. H2O.

NaHCO3.

Atoms of oxygen have a total of 8 electrons. Are these atoms stable, and why or why not? Yes, because the Octet Rule says stable atoms have 8 electrons. No, because the atoms have only 6 valence electrons, but need 8 for stability. Yes, because oxygen is in the air we breathe and it doesn't hurt us. No, because only atoms with 2 valence electrons are stable.

No, because the atoms have only 6 valence electrons, but need 8 for stability.

Which of the following distinguishes hydrogen bonds from covalent bonds? Only covalent bonds can form between molecules. Only hydrogen bonds can form between molecules. Only hydrogen bonds can form within molecules. Only ionic bonds can form within molecules.

Only hydrogen bonds can form between molecules.

Which of the following is true of polar covalent bonds? The same number of electrons are gained by one atom as are lost by another. They are rather weak bonds. Electrons are shared equally. The electrons are shared unequally.

The electrons are shared unequally.

Nucleotides are the building blocks of DNA and RNA. One nucleotide is also used in the high-energy molecule __________. cytosine triphosphate adenosine diphosphate adenosine triphosphate (ATP) guanosine diphosphate (GDP)

adenosine triphosphate (ATP)

In sickle cell anemia, there is a replacement in the amino acid sequence of hemoglobin of glutamic acid by valine. What is the difference between glutamic acid and valine? The R groups between the amino acids are different. The protein resulting from this substitution binds more oxygen. Glutamic acid has a lower pH than valine, so the resulting protein is more acidic. Valine does not form a correct peptide bond.

The R groups between the amino acids are different.

Adenosine triphosphate is considered a high-energy compound. But how is that energy transferred to the cellular machinery? Decay of ATP allows the release of pent-up energy. ATPase is used to combine phosphate molecules. This in turn provides energy for metabolism. ATP is generated from anabolic reactions. Therefore, it builds up electrons to transfer. The covalent bond between phosphates is broken down, releasing energy.

The covalent bond between phosphates is broken down, releasing energy.

Which of the following is not a result of hydrogen bonds? An enzyme has a unique shape that allows it to bond only with specific molecules. Two strands of DNA are linked together taking a shape similar to a ladder. Two hydrogen atoms join together to form a molecule of hydrogen gas. Some hair is straight, some wavy, and some very curly.

Two hydrogen atoms join together to form a molecule of hydrogen gas.

Water acts to dissolve molecules in the body. How does water dissolve the salt (NaCl) in your mouth from a salty pretzel? When water is added to the NaCl, NaCl is broken down by adding OH- to one element and H+ to the other. This is known as hydrolysis. Water acts as a solvent because the partial negative charge on the oxygen in water attracts sodium, while the partial positive charge on hydrogen attracts chloride. This results in the separation of sodium from chloride, thus breaking the ionic bond. Water acts as a cofactor for enzymes that dissolve the salt.

Water acts as a solvent because the partial negative charge on the oxygen in water attracts sodium, while the partial positive charge on hydrogen attracts chloride. This results in the separation of sodium from chloride, thus breaking the ionic bond.

Which of the following statements about water is true? Water is composed of nonpolar covalent molecules. Water is a poor solvent. Water molecules form hydration spheres around ions. Water composes the smallest portion of total body weight.

Water molecules form hydration spheres around ions.

As part of his diagnostic testing, baby Sean underwent a sweat chloride test that measures the levels of NaCl in the sweat from the skin on the forearm. How does the bond between NaCl form? Na atoms have a single electron in their valence, while Cl atoms have seven valence electrons. By sharing a pair of atoms and forming a covalent bond, both Cl and Na satisfy their valence shell requirements. Cl atoms only need one electron to complete their valence shells, while Na atoms have a single electron in their valence shells. Na and Cl atoms form a covalent bond by sharing a pair of electrons. But since the Cl atom has a greater electronegativity than the Na atom, the electrons are shared unequally; thus, they form a polar covalent bond. The positive Na cation forms a hydrogen bond with the negative Cl anion. When Na donates an electron to Cl, the Na atom becomes a cation and the Cl atom an anion. Since (+) and (-) charges attract each other, the Na+ and the Cl-; ions associate together, forming an ionic bond.

When Na donates an electron to Cl, the Na atom becomes a cation and the Cl atom an anion. Since (+) and (-) charges attract each other, the Na+ and the Cl-; ions associate together, forming an ionic bond.

A solute that removes hydrogen ions from a solution is __________. water a base a salt an acid

a base

When two monosaccharides undergo a dehydration synthesis, a polysaccharide is formed. two new monosaccharides are formed. a starch is formed. a disaccharide is formed. hydrolysis occurs.

a disaccharide is formed

In plasma, a typical body fluid, protein floating around would be considered to be which of the following? a solute, specifically both a colloid and an electrolyte a solute, specifically both a colloid and a nonelectrolyte a solvent

a solute, specifically both a colloid and an electrolyte

A solution containing more hydrogen ions than hydroxide ions is __________. basic neutral in equilibrium acidic

acidic

What is an ion? an atom that has lost one or more neutrons an atom that is sharing electrons with another atom an atom that loses all of its protons an atom that has either gained or lost electron(s)

an atom that has either gained or lost electron(s)

A salt may best be described as __________. an organic molecule created when an acid or base is chemically altered an inorganic molecule consisting of a cation and an anion an organic molecule used to flavor food an inorganic molecule that buffers solutions

an inorganic molecule consisting of a cation and an anion

Ionic bonds, such as in sodium chloride, __________. are bonds created by the gaining of electrons are formed by the association of ions with opposite charges share electrons are formed by the association of ions with the same charge

are formed by the association of ions with opposite charges

Which of the following is not produced through chemical bonding? the heart cells adipose (fat) tissue atoms

atoms

Which of the following are included in the four major classes of inorganic compounds? nucleic acids, salts, bases, and water water, acids, protein, and salts carbon dioxide, water, oxygen, and inorganic salts carbohydrates, fats, proteins, and water

carbon dioxide, water, oxygen, and inorganic salts

Juan had his broken arm in a cast for six weeks. When it was removed, he noticed that he had lost a lot of muscle mass. The loss of the muscle protein is considered what type of reaction? anabolic catabolic irreversible synthesis

catabolic

Ions with a + charge are called cations. anions. radicals. positrons. isotopes.

cations

Electrolytes are charged particles called ions that are dissolved in body fluids. Which of the following ions would be considered a major anion in the body? potassium calcium sodium chloride

chloride

Cholesterol is an important lipid derivative in our bodies. Which of the following is not a function associated with cholesterol? coordinate and direct local cellular activities important for cell growth and division serve as a precursor for testosterone maintain plasma membrane integrity

coordinate and direct local cellular activities

Which of the following correctly ranks the types of chemical bonds, in order, from strongest to weakest? hydrogen, covalent, ionic ionic, hydrogen, covalent hydrogen, ionic, covalent covalent, ionic, hydrogen

covalent, ionic, hydrogen

The formation of a complex carbohydrate is what type of reaction? dehydration synthesis decarboxylation hydrolysis phosphorylation

dehydration synthesis

Chemical reactions that absorb energy are said to be __________. endergonic exergonic exothermic thermal

endergonic

Electrons in an atom occupy an orderly series of electron shells or energy levels. energy fields. energy circles. electron clouds. electron lanes.

energy levels

In the formation of nonpolar covalent bonds, there is __________. unequal sharing of electrons equal sharing of protons and electrons donation of electrons equal sharing of electrons

equal sharing of electrons

Triglycerides are composed of glycerol and three __________. nucleotides fatty acids amino acids monosaccharides

fatty acids

Helium (He) has an atomic number of 2. It is chemically stable because it lacks electrons, thus the He atom is stable. readily ionizes to react with other atoms. has a full outer electron shell. will form a covalent bond with another He atom. is neutral in electrical charge.

has a full outer electron shell.

The ability of water to maintain a relatively constant temperature and then prevent rapid changes in body temperature is due to its __________. molecular structure high heat capacity boiling and freezing points solvent capacities

high heat capacity

Covalent bonds: involve the sharing of one to three pairs of electrons. always result in slight electrical charges at different atoms. involve the sharing of 8 pairs of electrons. always result in equal distribution of electrons between the atoms.

involve the sharing of one to three pairs of electrons.

Atoms of the same element whose nuclei contain the same number of protons, but different numbers of neutrons, are called heterotonics. isotopes. heterotopes. isotonics. homotopes.

isotopes

From the description of baby Sean's stool, what macromolecules do you suspect are NOT being digested? lipids and carbohydrates nucleic acids only carbohydrates and nucleic acids proteins only

lipids and carbohydrates

Enzymes __________ the activation energy required for a reaction to proceed to completion. increase lower equalize stabilize

lower

Radioactive atoms have unstable __________. nuclei neutrons protons electron clouds

nuclei

__________ molecules store and process genetic information. Ionic Nucleic acid Protein Lipid

nucleic acid

Molecules that store and process genetic information are the lipids. nucleic acids. carbohydrates. proteins. steroids.

nucleic acids

A __________ is to a nucleic acid as an amino acid is to a polypeptide. pyrimidine nucleotide purine base

nucleotide

An amino acid is to a protein as a ________ is to a nucleic acid. protein nucleotide purine neutron proton

nucleotide

The chemical properties of an atom are determined by the __________. number of electrons in the outermost electron shell mass of the nucleus number of neutrons in the nucleus number of protons in the nucleus

number of electrons in the outermost electron shell

Carbohydrates, lipids, and proteins are classified as inorganic molecules. organic molecules. bases. salts. acids.

organic molecules

The chemical behavior of an atom is determined by the size of the atom. mass of the nucleus. number of protons. number of neutrons. outermost electron shell.

outermost electron shell

By weight, which element is the most plentiful in the human body? potassium carbon oxygen sodium sulfur

oxygen

Which pH is more acidic, a pH of 3, a pH of 7, or a pH of 9? pH of 3 pH of 7 pH of 9

pH of 3

Which of the following molecules is a structural component of the plasma membrane? lipoprotein proteoglycan glycoprotein phospholipid

phospholipid

Molecules with two fatty acid chains and a phosphate group that form biological membranes are called phospholipids. disaccharides. prostaglandins. diglycerides. dipeptides.

phospholipids

If an atom loses an electron, it becomes a __________. positively charged cation negatively charged cation negatively charged anion positively charged anion

positively charged cation

The "atomic number" of an atom is determined by the number of ________ it has. protons + electrons electrons protons + neutrons neutrons protons

protons

The mass number represents the number of electrons in an ion. protons + neutrons. protons in an atom. neutrons + electrons. neutrons in an atom.

protons + neutrons.

Which type(s) of subatomic particles can be located within the nucleus of an atom? protons and electrons neutrons only protons and neutrons electrons only

protons and neutrons

The alpha-helix is an example of the __________ level of protein structure. primary quaternary tertiary secondary

secondary

A shortage of steroids in the body would result in a shortage of plasma membranes. glycogen. sex hormones. proteins. sex hormones and plasma membranes.

sex hormones and plasma membranes.

Which of these lists contains only trace elements? cobalt, calcium, sodium sulfur, chlorine, oxygen silicon, fluorine, tin selenium, hydrogen, calcium boron, oxygen, carbon

silicon, fluorine, tin

If solution A contains a weak acid, and solution B contains a strong acid, in which solution will you observe a one-way reaction? solution A solution B Neither: both solutions will react equally. Both: once in solution, the acid dissociates and cannot reform.

solution B

When placed in water, an inorganic compound dissociates 99 percent, forming hydrogen ions and anions. This compound would be a weak acid. weak base. strong base. salt. strong acid.

strong acid

Cholesterol, phospholipids, and glycolipids are examples of lipid drugs. prostaglandins. steroids. dietary fats. structural lipids.

structural lipids

Before an enzyme can work, a __________ molecule must bind at the __________ site. product; neutral substrate; active carboxyl; anionic calcium; regulatory

substrate; active

An example of an organic substance is sucrose. oxygen. carbonic acid. nitric oxide. sodium chloride.

sucrose

A dust particle floating on a water surface illustrates static electricity. surface tension. hydrophilic attraction. chemical tension. heat capacity.

surface tension

The structure of RNA differs from DNA in that DNA contains pyrimidines but not purines. RNA contains purines but not pyrimidines. the backbone of RNA contains ribose. DNA contains purines but not pyrimidines. RNA contains pyrimidines but not purines.

the backbone of RNA contains ribose.

When an ionic bond forms, which part(s) of the atoms are directly involved? the outermost electrons the protons the neutrons both the protons and the electrons

the outermost electrons

The pyrimidine bases found in DNA are ________ and cytosine. thymine cytosine niacin adenine uracil

thymine

Most of the fat found in the human body is in the form of monoglycerides. prostaglandins. triglycerides. phospholipids. cholesterol.

triglycerides

The average time between synthesis and breakdown is known as the ________ time. turnover metabolism catabolism specificity anabolism

turnover

Which parts of atoms can interact (react) to form chemical bonds? the orbitals valence electrons protons the nucleus of each atom

valence electrons

Foods are broken down into their building blocks by adding water. This would be an example of which characteristic of water? Water acts as a cushion. Water acts as a reactant. Water has a high heat of vaporization. Water acts as a lubricant.

water acts as a reactant

An example of an inorganic substance is water and carbon dioxide. glycerol. fructose. carbon dioxide. water.

water and carbon dioxide.