SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.

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1 Exam Name SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. Figure 2.1 Using Figure 2.1, match the following: 1) Lipid. 2) Functional protein. 3) Nucleotide. 4) Polysaccharide. 5) Monosaccharide. 1

2 Figure 2.2 Using Figure 2.2, match the following: 6) Deoxyribose sugar. 7) Thymine. 8) Guanine. 9) Phosphate. 10) Hydrogen bond. 2

3 MATCHING. Choose the item in column 2 that best matches each item in column 1. Match the following: 11) A bond in which electrons are shared unequally. 12) A bond in which electrons are completely lost or gained by the atoms involved. 13) A bond in which electrons are equally shared. A) Hydrogen bond B) Polar covalent bond C) Nonpolar covalent bond D) Ionic bond 14) A type of bond important in tying different parts of the same molecule together into a three-dimensional structure. Match the following: 15) Electrically charged particle due to loss of an electron. 16) Neutral subatomic particle. 17) Smallest particle of an element that retains its properties. A) Neutron B) Cation C) Atom D) Molecule 18) Smallest particle of a compound that still retains its properties. Match the following: 19) Water. 20) Carbon. Match the following: 21) Anything that occupies space and has mass. 22) Although a man who weighs 175 pounds on Earth would be lighter on the moon and heavier on Jupiter, his would not be different. A) Element B) Compound A) Weight B) Matter C) Mass 23) Is a function of, and varies with, gravity. TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. 24) A synthesis reaction always involves bond formation. 3

4 25) Chemical properties are determined primarily by neutrons. 26) A charged particle is correctly called an ion. 27) Isotopes differ from each other only in the number of electrons contained. 28) About 60 to 80% of the volume of most living cells consists of organic compounds. 29) Lipids are a poor source of stored energy. 30) Glucose is an example of a monosaccharide. 31) A molecule consisting of one carbon atom and two oxygen atoms is correctly written as CO2. 32) The lower the ph, the higher the hydrogen ion concentration. 33) Covalent bonds are generally weaker than ionic bonds. 34) Hydrogen bonds are strong bonds. 35) All organic compounds are covalently bonded. MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 36) In general, the category of lipids that we refer to as oils have: A) long fatty acid chains. B) a high degree of saturated bonds. C) a high degree of unsaturated bonds. D) a high water content. 37) The genetic information is coded in DNA by: A) the regular alteration of sugar and phosphate molecules. B) the sequence of the nucleotides. C) the structure of the histones. D) the three-dimensional structure of the double helix. 38) Which of the following is not true of proteins? A) They appear to be the molecular carriers of the coded hereditary information. B) Their function depends on the three-dimensional shape. C) Some types are called enzymes. D) They may be denatured or coagulated by heat or acidity. 39) The single most abundant protein in the body is: A) glucose. B) hemoglobin. C) collagen. D) DNA. 40) Carbohydrates are stored in the liver and muscles in the form of: A) glucose. B) triglycerides. C) cholesterol. D) glycogen. 4

5 41) The speed or rate of a chemical reaction is influenced by all of the following except: A) the presence or absence of carbon. B) the temperature. C) the concentration of the reactants. D) the presence of catalysts or enzymes. 42) Salts are always: A) hydrogen bonded. B) ionic compounds. C) double covalent compounds. D) single covalent compounds. 43) A solution that has a ph of 2 could best be described as being: A) basic. B) acidic. C) neutral. D) slightly acidic. 44) Which of the following would be regarded as an organic molecule? A) H2O B) NaOH C) CH4 D) NaCl 45) A chain of 25 amino acids would be called a: A) nucleotide. B) protein. C) starch. D) peptide. 46) A long chain of simple sugars would be a: A) protein. B) nucleic acid. C) polysaccharide. D) monosaccharide. 47) Carbohydrates and proteins are built up from their basic building blocks by the: A) addition of a water molecule between each two units. B) removal of a nitrogen atom between each two units. C) addition of a carbon atom between each two units. D) removal of a water molecule between each two units. 48) Which statement about enzymes is false? A) Enzymes are composed mostly of protein. B) Enzymes raise the activation energy needed to start a reaction. C) Enzymes may be damaged by high temperature. D) Enzymes are organic catalysts. 49) Select the statement that is most correct regarding chemical bonds. A) Ionic bonds involve the sharing of electrons between two atoms. B) Multiple bonds are not possible with covalent bonding. C) Covalent bonding involves the transfer of one or more electrons from one atom to another. D) Hydrogen bonds are very weak and often involve water. 50) Select the most correct statement regarding nucleic acids. A) RNA is a long, single-stranded molecule made up of the nucleotides A, T, G, and C. B) DNA is a long, double-stranded molecule made up of A, T, G, and C nucleotides. C) Three forms exist: DNA, RNA, and TDNA. D) TDNA is considered a molecular slave of DNA. 5

6 51) Select the correct statement about isotopes. A) All the isotopes of an element have the same number of neutrons. B) Isotopes are rare and occur only in the heavier elements. C) All the isotopes of an element are radioactive. D) Isotopes of the same element have the same atomic number but differ in their atomic weights. 52) The four elements that make up about 96% of body matter are: A) carbon, oxygen, phosphorus, calcium. B) nitrogen, hydrogen, calcium, sodium. C) sodium, potassium, hydrogen, oxygen. D) carbon, oxygen, hydrogen, nitrogen. 53) Atom X has seventeen protons. How many electrons are in its valence shell? A) 3 B) 10 C) 5 D) 7 54) If atom X has an atomic number of 74 it would have. A) 37 protons and 37 neutrons B) 74 protons and roughly the same number of neutrons C) 37 electrons D) 74 protons and no neutrons 55) The formula C6H12O6 means: A) there are 6 calcium, 12 hydrogen and 6 oxygen atoms. B) the substance is a colloid. C) the molecular weight is 24. D) there are 12 hydrogen, 6 carbon and 6 oxygen atoms. 56) The chemical symbol O = O means: A) the atoms are double bonded. B) zero equals zero C) both atoms are bonded and have zero electrons in the outer orbit. D) this is an ionic bond with two shared electrons. 57) Dipole is: A) a type of reaction. B) an organic molecule. C) a type of bond. D) a polar molecule. 58) CH4 means: A) there are four carbon and four hydrogen atoms. B) this is an inorganic molecule. C) there is one carbon and four hydrogen atoms. D) this was involved in a redox reaction. 59) Amino acids joining together to make a peptide is a good example of a reaction. A) reversible B) exchange C) synthesis D) decomposition 60) The following is not an electrolyte. A) NaOH B) H2O C) HCl D) Ca2CO3 6

7 61) Grapefruit juice (ph 3) has times the concentration of coffee (ph 5). A) 20 B) 100 C) 10 D) ) Sucrose is a. A) polysaccharide B) monosaccharide C) triglyceride D) disaccharide 63) Neutral fats have a ratio of fatty acids to glycerol. A) 2:1 B) 3:1 C) 1:1 D) 4:1 SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 64) The atomic number is equal to the number of. 65) Molecules such as methane that share electrons have bonds. 66) Polysaccharides with long chains of similar units are called. 67) In a DNA molecule guanine would connect to. 68) The molecule directly provides energy for cellular work. 69) Starch is the stored carbohydrate in plants while is the stored carbohydrate in animals. 70) Explain the difference between potential and kinetic energy. 71) What advantages does ATP have in being the energy currency molecule? 72) Describe the factors that affect chemical reaction rates. 73) Protons and electrons exist in every atom nucleus except hydrogen. Is this statement true or false and why? 74) Name four things you know about enzymes. ESSAY. Write your answer in the space provided or on a separate sheet of paper. 75) How can DNA be used to "fingerprint" a suspect in a crime? 7

8 Answer Key Testname: 2-CHEMISTRY.TST SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 1) D 2) B 3) E 4) C 5) A 6) B 7) D 8) E 9) C 10) A MATCHING. Choose the item in column 2 that best matches each item in column 1. 11) B 12) D 13) C 14) A 15) B 16) A 17) C 18) D 19) B 20) A 21) B 22) C 23) A TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. 24) TRUE 25) FALSE 26) TRUE 27) FALSE 28) FALSE 29) FALSE 30) TRUE 31) TRUE 32) TRUE 33) FALSE 34) FALSE 35) TRUE MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 36) C 37) B 38) A 39) C 40) D 1

9 Answer Key Testname: 2-CHEMISTRY.TST 41) A 42) B 43) B 44) C 45) D 46) C 47) D 48) B 49) D 50) B 51) D 52) D 53) D 54) B 55) D 56) A 57) D 58) C 59) C 60) B 61) B 62) D 63) B SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question. 64) protons 65) covalent 66) polymers 67) cytosine 68) ATP 69) glycogen 70) Potential energy is the energy an object has relative to position. Kinetic energy is energy associated with a moving object. 71) It is easy to store; it releases just the right amount of energy for the cell's needs so it is protected from excessive energy release. A universal energy currency is efficient because a single system can be used by all the cells in the body. 72) Temperature increases kinetic energy and therefore the force of molecular collisions. Particle size: smaller particles move faster at the same temperature and therefore collide more frequently; also, smaller particles have more surface area given the same concentration of reactants. Concentration: the higher the concentration, the greater the chance of particles colliding. Catalysts increase the rate of the reaction at a given temperature. Enzymes are biological catalysts. 73) False - Hydrogen has one proton and one electron. It is the neutron that hydrogen does not have. 74) 1. They are proteins. 2. They have specific binding sites for specific substrates. 3. They lower the activation barrier for a specific reaction. 4. The names end in ase. 5. They can be denatured. 6. They can be used again and again. ESSAY. Write your answer in the space provided or on a separate sheet of paper. 75) The DNA of a person is unique to that individual. By obtaining the DNA from nucleated cells from the crime scene (e.g., tissue, sperm), heating it gently to separate the strands, combining it with the suspect's DNA, and allowing it to reanneal, the relatedness can be determined by the amount of base pairing. 2