anatomy and physiology 1: chapter 2

If an element is composed of atoms with an atomic number of 6 and a mass number of 14, then the nucleus of a neutral atom of this element contains - 6 protons and 8 neutrons. - 6 protons and 8 electrons. - 8 neutrons. - 6 protons. - 8 electrons.

6 protons and 8 neutrons

By weight, which element is the second most abundant in the human body? - calcium - oxygen - nitrogen - hydrogen - carbon

carbon

The molecule CO2 is known as - carbonized oxygen. - carbon dioxide. - carbon monoxide. - carbon oxide. - carbonated oxygen.

carbon dioxide.

Which of the following are large polysaccharides and major dietary source of energy? - lactose - sucrose - fructose - maltose - starch

starch

Which of the following is a structural component of hormones? - steroids - phospholipids - prostaglandins - monoglycerides - lauric acid

steroids

Hydrophilic molecules readily associate with - both lipid molecules and hydrophobic molecules. - water molecules. - cholesterol. - hydrophobic molecules. - lipid molecules.

water molecules.

Oppositely charged ions in solution are prevented from combining by - heat capacity of water. - water's nonpolar nature. - free radicals. - hydrogen bonding. - hydration spheres

hydration spheres

The weakest bond between two atoms is the ________ bond. - covalent - ionic - hydrogen - polar - nonpolar

hydrogen

Which element commonly has only a proton as its nucleus? - neon - argon - helium - hydrogen - None of the answers is correct.

hydrogen

Nonpolar organic molecules are good examples of - molecules that will dissociate when placed into water. - hydrophilic compounds. electrolytes. - solutes. - hydrophobic compounds.

hydrophobic compounds.

Molecules that do not readily dissolve in water are called - isophobic. - hydrophobic. - electrolytes. - isophilic. - hydrophilic.

hydrophobic.

Atoms of the same element whose nuclei contain the same number of protons, but different numbers of neutrons, are called - trace elements. - isotopes. - ions. - isomers. - principal elements.

isotopes.

All of the following are correct regarding RNA except - the nitrogenous base is made of adenine, guanine, cytosine, and uracil. - it contains a double helix. - molecular shape varies with hydrogen bonding along the length of the strand. - it makes protein as directed by DNA. - it contains ribose sugar.

it contains a double helix.

A solution containing equal numbers of hydrogen ions and hydroxide ions is - acidic. - basic. - alkaline. - neutral. - in equilibrium.

neutral

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

nucleic acids.

What is the individual subunit of nucleic acid called? - purine - nucleotide - ribonucleic acid - pyrimidine - deoxyribonucleic acid

nucleotide

The center of an atom is called the - nucleus. - element. - electron cloud. - proton. - molecule.

nucleus

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

organic molecules.

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

outermost electron shell.

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

oxygen

The molecule O2 is known as - oxygen and organic. - oxide. - oxyous. - organic. - oxygen

oxygen

Which pH is closest to normal blood pH? - pH 2 - pH 8 - pH 7 - pH 3 - pH 4

pH 7

A sequence of amino acids bonded together in a linear chain is called a - secondary structure. - tripeptide. - tertiary structure. - primary structure. - quaternary structure.

primary structure.

Each of the following is an example of an inorganic compound except - salts. - bases. - acids. - proteins. - water.

proteins

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

protons

The nucleus of an atom consists of - neutrons. - protons + neutrons. - electrons. - protons + electrons. - protons.

protons + neutrons.

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

12.0

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

18

What is the relationship between an atom and matter? (Module 2.1A) - An atom is a particle with a negative electrical charge, and matter is mass within a gravitational field. - An atom is the smallest stable unit of matter, and matter is a pure substance consisting only of atoms with the same atomic number. - An atom is the smallest stable unit of matter, and matter is anything that takes up space and has mass. - An atom is a chemical substance made up of two or more different elements in a fixed proportion, and matter is a pure substance consisting only of atoms with the same atomic number. - An atom is the largest stable unit of matter, and matter is anything that takes up space and has mass.

An atom is the smallest stable unit of matter, and matter is anything that takes up space and has mass.

________ are soluble inorganic compounds whose solutions will conduct an electric current. - Enzymes - Proteins - Electrolytes - Lipids - Ions

Electrolytes

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

What is an important characteristic of amino acid uracil? - It is found both in DNA and RNA. - It is found only in RNA. - It is an essential part of quaternary proteins. - It is not found in DNA or RNA. - It is found only in DNA.

It is found only in RNA.

________ molecules are compounds that contain carbon as the primary structural atom. - Complex - Exergonic - Organic - Endergonic - Inorganic

Organic

Which of the following is correct regarding enzymes? - They are made of lipids. - They slow down cellular reactions. - They are organic catalysts and are made of proteins. - They bind to the active site of substrates. - They are released during cellular injury.

They are organic catalysts and are made of proteins.

Substrate molecules bind to enzymes at the ________ sites. - reactant - carboxyl - amino - neutral - active

active

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

adenosine triphosphate.

If a substance has a pH that is greater than 7, it is - a salt. - neutral. - acidic. - a buffer. - alkaline.

alkaline.

In an aqueous solution, cations are attracted toward - anions. - buffers. - hydrogen ions. - water. - salt.

anions.

Ions with a negative charge are called - cations. - positrons. - anions. - protons. - polar molecules.

anions.

All of the following are true concerning enzymes except that they - affect only the rate of a chemical reaction. - function as biological catalysts. - are consumed during the reaction. - lower the activation energy required for a reaction. - are proteins.

are consumed during the reaction.

Carbohydrate molecules - contain the genetic information found in cells. - are the body's most readily available source of energy. - are the building blocks of cellular membranes. - form the regulatory molecules known as enzymes. - are composed of C, H, O, and N atoms.

are the body's most readily available source of energy.

The actual mass of an atom is known as its - atomic mass unit. - atomic number. - element number. - mass number. - atomic weight.

atomic weight.

The smallest stable units of matter are - atoms. - molecules. - protons. - neutrons. - electrons.

atoms.

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

base; acid

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

cations

Which of the following is a structural component of cell membranes? - diglycerides - cholesterol - prostaglandins - glycogen - lauric acid

cholesterol

When atoms complete their outer electron shell by sharing electrons, they form - anions. - hydrogen bonds. - covalent bonds. - ionic bonds. - cations.

covalent bonds.

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

glycogen

In a molecule of oxygen gas, two pairs of electrons are shared equally by two oxygen atoms. The type of bond that is formed is an example of a - triple nonpolar covalent bond. - double polar covalent bond. - hydrogen bond. - double nonpolar covalent bond. - single trivalent bond.

double nonpolar covalent bond.

Ionic bonds are formed when - a pair of electrons is shared unequally by two atoms. - hydrogen forms bonds with negatively charged atoms. - electrons are completely transferred from one atom to another. - atoms share electrons. - two or more atoms lose electrons at the same time

electrons are completely transferred from one atom to another.

A(n) ________ is a pure substance composed of atoms. - electron - compound - element - molecule - neutron

element

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

glucose

Which of the following substances would be most acidic? - stomach secretions, pH = 1 - tomato juice, pH = 4 - urine, pH = 6 - white wine, pH = 3 - lemon juice, pH = 2

stomach secretions, pH = 1

Which of the following is a result of convoluted coiling and folding that grants protein its final three- dimensional shape? - pentagonal - secondary structure - quaternary structure - primary structure - tertiary structure

tertiary structure

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

the backbone of RNA contains ribose.