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84 Cards in this Set
- Front
- Back
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Atoms are the smallest particles of any ________ carrying all the properties of that element.
A) molecule B) macromolecule C) element D) metal |
element
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The capability of any atom (other than inert elements) to react or to form any molecule depends on the
A) number of electrons B) number of protons C) number of neutrons D) total number of protons and electrons |
number of electrons
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An element has 7 electrons, 7 protons, and 7 neutrons, what will be the atomic weight of that element?
A) 7 B) 14 C) 21 D) 0 |
14
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Atomic number of an element is determined by the
A) number of neutrons B) position of electrons C) number of protons D) total number of electrons and protons |
number of protons
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A covalent bond is characterized by
A) sharing electrons by the atoms B) sharing electrons by one atom and gaining electrons by the other C) the attractive force between oppositely charged atoms D) involvement of too many different forces |
sharing electrons by the atoms
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In ionic bonding
A) only non-polar molecules are involved B) a "sea of electrons" is formed C) electrons are transferred from one atom to another D) two hydrogen atoms share one pair of electrons |
electrons are transferred from one atom to another
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When an atom is electrically charged (either positive or negative), it is known as a(n)
A) molecule B) radiation C) ion D) element |
ion
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Which of the following best describes a proton?
A) A proton has one positive charge, mass of one unit and found in nucleus. B) A proton has negative charge, mass of one unit and found in nucleus. C) A proton has one negative charge, no mass and found in nucleus. D) A proton can have both positive and negative charge and found in nucleus. |
A proton has one positive charge, mass of one unit and found in nucleus.
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Peptide bonds are found in all the molecules of
A) carbohydrates B) organic compounds C) lipids D) proteins |
proteins
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The hydrogen and oxygen atoms in a molecule of water are held together by a(an) __________ bond.
A) polar covalent B) ionic C) peptide D) hydrogen |
polar covalent
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Bonding is necessary for the formation of
A) molecules B) ionic radiation C) elements D) atoms |
molecules
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Which statement about hydrogen bonding is true?
A) Hydrogen bond is formed by sharing electrons between atoms. B) Hydrogen bond also requires formation of ions. C) Hydrogen bond is a weak force between atoms in a molecule but is of enormous importance in physiology. D) Hydrogen bond is nothing but a different form of hydrogen ion. |
Hydrogen bond is a weak force between atoms in a molecule but is of enormous importance in physiology.
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A molecule is said to be _______ when it gains one or more electrons.
A) a free radical B) electrified C) oxydized D) reduced |
reduced
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When two atoms are held together because their valence electrons orbit around both of them, they are united by a(n) ________ bond.
A) ionic B) hydrogen C) covalent D) electron |
covalent
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The complex and unique three-dimensional structure of a protein molecule is maintained largely by __________ bonds.
A) electrovalent B) covalent C) ionic D) hydrogen |
hydrogen
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When molecules are formed by sharing electrons equally, those molecules are called
A) salt molecules B) polar covalent C) non-polar covalent D) macromolecules |
non-polar covalent
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Which of the following statements about molecules is true?
A) When two or more atoms bond, they form a new structure called a molecule. B) Molecules have to be formed by atoms of same type of elements. C) Molecules have to be formed by atoms of different type of elements. D) All of the above statements are false. |
When two or more atoms bond, they form a new structure called a molecule.
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An example of macromolecules in our body includes
A) nucleic acids B) proteins C) carbohydrates and lipids D) all of the above |
all of the above
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Which statement about solubility of a compound is TRUE?
A) Compounds are always solid and cannot be dissolved in any solution. B) Solubility properties of compounds are completely unknown. C) Compounds are always liquid and can be dissolved in any solution. D) Compounds, depending on their structure, could be water-soluble or fat-soluble. |
Compounds, depending on their structure, could be water-soluble or fat-soluble.
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A(n) _______ reaction is one in which two or more smaller molecules with low free energy are combined into a larger molecule with greater free energy.
A) endergonic B) exergonic C) synthesis D) decomposition |
synthesis
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An oxidizing agent _______ the molecule it oxidizes.
A) increases the size of B) adds H or H2 to C) adds electrons to D) reduces the free energy of |
reduces the free energy of
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A reduction reaction is always accompanied by
A) an oxidation reaction B) decomposition C) some energy release D) huge nuclear decay |
an oxidation reaction
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Which of the following is a synthesis reaction?
A) Two amino acids are bonded together to form a dipeptide. B) Sucrose is chemically broken down to form one molecule of glucose and one molecule of fructose. C) Sodium chloride is dissolved in water. D) Several dipeptide chains are formed from digestion of a long polypeptide chain. |
Two amino acids are bonded together to form a dipeptide.
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Physical and chemical changes occurring in the body are defined as
A) metabolism. B) a synthesis reaction. C) a decomposition reaction. D) digestion. |
metabolism.
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Catabolism is a collective term for all the body's _______ reactions.
A) endergonic B) decomposition C) reduction D) synthesis |
decomposition
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If an atom has 3 electrons in its second shell and its first shell is filled, it will tend to
A) lose 3 electrons from its second shell B) lose all of the electrons from its first shell C) lose all of the electrons from its first and second shells D) gain 2 electrons in its second shell |
lose 3 electrons from its second shell
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Electrolytes are substances that
A) form covalent bonds with water. B) ionize when dissolved in water. C) cannot conduct electricity in solution. D) are not found in the human body in any appreciable amounts. |
ionize when dissolved in water.
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Synthesis reactions are particularly important in the body for
A) release of energy B) digestion of food products C) growth of body parts D) neutralization of acids by buffers |
growth of body parts
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A chemical reaction in which pairs of two different molecules trade positions with one another is called __________.
A) decomposition B) exchange C) reversible D) synthesis |
exchange
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Which of the following pairs is mismatched?
A) synthesis reaction - two reactants combine to form a larger product B) decomposition reaction - large reactant broken into smaller products C) oxidation - gain of electrons D) dehydration reaction - water is a product of the reaction |
oxidation - gain of electrons
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Which of the following factors will influence the rate of chemical reactions?
A) temperature B) concentration of reactants C) presence of catalysts D) all of these will influence the rate of chemical reactions |
all of these will influence the rate of chemical reactions
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A base is defined as a chemical that
A) accepts H+ B) releases H+ C) releases H2O D) accepts OH– |
accepts H+
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A solution that resists changes in pH when H+ or OH–ions are added to it, is called a(n)
A) buffer B) base C) alkali D) neutral solution |
base
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When hydrogen ion concentration increases, pH
A) increases B) decreases C) doesn't change D) changes to neutral |
decreases
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The pH is a scale that measures the
A) concentration of hydrogen ions in solution B) amounts of salts dissolved in water C) number of hydroxyl ions in water D) strength of an electrical current carried by a solution |
concentration of hydrogen ions in solution
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A(n) _____________ solution contains equal numbers of hydrogen and hydroxyl ions.
A) acidic B) basic C) alkaline D) neutral |
neutral
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Substances formed by the reaction between an acid and a base are known as
A) buffers B) salts C) compounds D) macromolecules |
salts
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Which one among the following is an example of a salt?
A) calcium carbonate B) sodium chloride C) magnesium sulfate D) all of the above are examples of salt |
all of the above are examples of salt
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Inorganic substances dissolve in water or react with water to release ions. Thus they are known as
A) salts B) electrolytes C) bases D) inorganic compounds |
electrolytes
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To maintain homeostasis which of the following conditions are necessary?
A) Electrolytic imbalance is necessary. B) Water volume has to be very low. C) Electrolyte balance is key for maintaining homeostasis. D) There should not be any formation of ions. |
Electrolyte balance is key for maintaining homeostasis.
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Which statement regarding the role of water in the body is true?
A) Water can absorb and transport heat. B) Water is the most abundant compound in the body. C) Water carries nutrients as well as waste materials. D) All of the above statements are true regarding the role of water in the body. |
All of the above statements are true regarding the role of water in the body.
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Organic compounds are those that always contain
A) carbon and oxygen B) carbon and hydrogen C) hydrogen and oxygen D) sulfur and phosphorus |
carbon and hydrogen
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Carbohydrates are also known as
A) harmful chemicals B) primary source of energy C) necessary components for protein formation D) unsaturated compounds |
primary source of energy
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A simple carbohydrate is characterized by
A) having a molecular formula of C6H12O6 B) being a building block of nucleic acids C) having several polypeptide chains joined together D) having too many double bonds |
having a molecular formula of C6H12O6
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A major function of Deoxyribo Nucleic Acids (DNA) is that DNA
A) helps in the synthesis of varieties of nucleic acids B) is important in building muscles C) stores genetic information D) is important in building carbohydrates |
stores genetic information
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Which of the following statements about lipids is true?
A) Lipids are insoluble in water. B) Cholesterol and fats are different varieties of lipids. C) Fat molecules contain C, H, and O, but the proportion of oxygen is much smaller than in carbohydrates. D) All of the above statements are true about lipids. |
All of the above statements are true about lipids.
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A general characteristic of nucleic acids is that they are
A) very small, simple molecules B) a combination of inorganic and organic compound C) all composed of building blocks called nucleotides D) a type of inorganic compound |
all composed of building blocks called nucleotides
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A protein can become denatured when
A) bonds between C-O are broken B) weak hydrogen bonds are broken C) peptide bonds are broken D) none of the above |
A protein can become denatured when
A) bonds between C-O are broken B) weak hydrogen bonds are broken C) peptide bonds are broken D) none of the above |
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Which of the following statements about proteins is true?
A) Proteins are necessary for body structure and they serve as energy sources, and chemical messengers. B) Proteins are made up with C, H, O, and N, and sometimes S. C) They can act as enzymes. D) All of the above statements are about proteins. |
All of the above statements are about proteins.
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Which of the following is an organic compound?
A) hydrochloric acid (HCl) B) salt (NaCl) C) glucose (C6H12O6) D) water (H2O) |
glucose (C6H12O6)
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The molecule used most frequently by cells as a fuel belongs to which of the following groups?
A) prostaglandins B) carbohydrates C) nucleic acids D) steroids |
carbohydrates
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Proteins are composed of building blocks called
A) triacylglycerols B) phospholipids C) amino acids D) monosaccharides |
amino acids
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The primary structure of a protein is determined by the
A) number of polypeptide chains in the molecule B) sequence of amino acids in the polypeptide chain C) folded, helical nature of the molecule D) the number of polypeptide and hydrogen bonds |
sequence of amino acids in the polypeptide chain
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Which of the following is a source of nitrogen for the body?
A) carbohydrates B) water C) proteins D) glucose |
proteins
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Which of the following would be classified as a lipid?
A) cholesterol—a steroid B) alanine—an amino acid C) starch—a polysaccharide D) catalase—an enzyme |
cholesterol—a steroid
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Adjacent amino acids in a polypeptide chain are held together by _________ bonds.
A) hydrogen B) ionic C) Van der Waals D) peptide |
peptide
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A(n) _______ is any chemical that easily donates electrons to other chemicals.
A) oxidizing agent B) reducing agent C) catalyst D) reactant |
reducing agent
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Neutrons are subatomic particles that are located
A) in the nucleus and have a positive charge. B) in the nucleus and have no charge. C) in the nucleus and have a negative charge. D) around the nucleus and have a positive charge. E) around the nucleus and have a negative charge. |
in the nucleus and have no charge.
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Most of the volume of an atom is occupied by the
A) electrons. B) neutrons. C) protons. D) protons and neutrons. |
electrons.
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The simplest type of matter with unique chemical properties is
A) an electron. B) an element. C) a neutron. D) a proton. E) an isotope. |
an element.
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The atomic number of an element is equal to the number of
A) electrons in each atom. B) neutrons in each atom. C) protons in each atom. D) protons plus electrons in each atom. E) neutrons plus electrons in each atom. |
protons in each atom.
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Which of the pairs below are equal to each other in an atom?
A) neutrons and protons B) protons and electrons C) neutrons and electrons D) atomic number and mass number E) mass number and electrons |
protons and electrons
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14N and 15N are
A) different elements. B) atoms with different atomic numbers. C) isotopes of the same element. D) identical except for different numbers of electrons. E) identical except for different numbers of protons. |
isotopes of the same element.
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In the human body, which element makes up the largest percentage of atoms by number?
A) carbon B) fluorine C) hydrogen D) nitrogen E) oxygen |
hydrogen
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The chemical behavior of an atom is determined largely by
A) its number of protons. B) its outermost electrons. C) the size of the electron cloud. D) its mass. E) its weight. |
its outermost electrons.
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Chemical bonding occurs when the __________ are transferred or shared between atoms.
A) outer protons B) largest neutrons C) outermost electrons D) innermost electrons E) outermost protons |
outermost electrons
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Ionic bonding occurs when
A) a cation and an anion are attracted to each other. B) two cations are attracted to each other. C) two anions are attracted to each other. D) two atoms lose protons. E) two atoms lose neutrons. |
two anions are attracted to each other.
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An atom that gains an electron
A) becomes a cation. B) becomes a different isotope of the same element. C) has a different atomic number. D) becomes an anion. E) explodes. |
becomes an anion
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When two hydrogen atoms each share an electron with an oxygen atom (H2O),
A) polar covalent bonding occurs. B) nonpolar covalent bonding occurs. C) ionic bonding occurs. D) metallic bonding occurs. E) it is called a james bond. |
polar covalent bonding occurs.
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When a positively charged hydrogen atom of one water molecule is attracted to a negatively charged oxygen atom of another water molecule,
A) covalent bonding occurs. B) hydrogen bonding occurs. C) ionic bonding occurs. D) metallic bonding occurs. |
hydrogen bonding occurs.
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Potassium chloride is formed when a potassium ion (K+) is attracted to a chloride ion (Cl-). Therefore, potassium chloride is
A) an atom. B) a molecule. C) a compound. D) a metal. E) all of these |
a compound.
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If potassium chloride is placed in water, it will
A) form strong covalent bonds with the water molecules. B) dissociate into separate ions. C) not mix with the water. D) become nonpolar. E) form covalent potassium chloride molecules. |
dissociate into separate ions.
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Which of these substances is an electrolyte?
A) canola oil B) glucose C) fructose D) sodium chloride E) sucrose |
sodium chloride
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A synthesis reaction
A) may be a dehydration reaction. B) results in catabolism. C) may be a hydrolysis reaction. D) breaks down a larger reactant into two or more smaller products. E) all of these |
may be a dehydration reaction.
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All of the synthesis and decomposition reactions that take place in the body are collectively referred to as
A) anabolism. B) catabolism. C) dissociation. D) electrolytes. E) metabolism. |
metabolism.
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The gain of an electron by an atom is called
A) anabolism. B) catabolism. C) oxidation. D) reduction. E) synthesis. |
reduction.
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In which of these types of reactions does an equilibrium occur?
A) decomposition reaction B) synthesis reaction C) exchange reaction D) reversible reaction |
reversible reaction
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Chemical events in cells are regulated primarily by mechanisms that control either the concentration or the activity of
A) acids. B) bases. C) enzymes. D) lipids. E) sugars. |
enzymes
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In which of these reactions is energy released?
A) hydrolysis of ATP to ADP B) production of ATP from ADP C) photosynthesis D) production of glucose from CO2 and H2O E) all of these |
hydrolysis of ATP to ADP
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Osmolality
A) reflects the number of atoms in a solution. B) of normal body fluid is about 300 osmoles. C) influences the movement of water into and out of cells. D) indicates the percent of solute by weight per volume of solution. E) reflects the percent of solvent in a solution. |
influences the movement of water into and out of cells.
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If the number of hydrogen ions in a solution is increased, the
A) solution becomes more acidic. B) solution becomes more alkaline (basic). C) pH of the solution will be increased. D) solution is a buffer. E) pH of the solution remains unchanged. |
solution becomes more acidic.
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Potassium hydroxide (KOH) dissociates in solution to produce K+ and OH-; therefore it is classified as
A) an acid. B) a base. C) a buffer. D) a neutral substance. |
a base
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Which of these is a monosaccharide?
A) sucrose B) starch C) glycogen D) glucose E) cellulose |
glucose
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Enzymes
A) are always composed of monosaccharides. B) function by raising the activation energy required for a reaction. C) can control many different reactions. D) generally decrease the rate of chemical reactions. E) sometimes require cofactors to be functional. |
sometimes require cofactors to be functional.
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