Biology Questions and Answers



PART TWO:
Instructions: Read the question and choose the best answer for it. At the end of each question, there is a correct answer that best answers the question.
 
Students in a classroom
 (1) Which type of molecule is composed of (CH2O) units?
(A). Carbohydrate
(B). Nucleic acid
(C). Lipid
(D). Protein
Correct Answer:  A.
(2) Which of the following statements regarding protein structure is FALSE?
(A). The primary structure is formed by covalent bonding between amino acid subunits.
(B). Secondary structures are formed only from hydrogen bonds.
(C). Quaternary structures involved multiple polypeptides.
(D). Tertiary structures are formed only from covalent bonds.
Correct Answer:  D.
(3) Using the following information, C=12, H=1, and O=16 calculate molecular weight of ethanol (C2H5OH).
(A). 34
(B). 46
(C). 96
(D). 33
(E) The answer cannot be determined.
Correct Answer:  B.
(4)Structurally, ATP is most like which type of molecule?
(A). Carbohydrate
(B). Lipid
(C). Protein
(D). Nucleic acid
Correct Answer:  D.
(5)Which of the following is true of functional groups?
(A). Functional groups typically bind to inorganic molecules.
(B). Functional groups confer different properties, such as hydrophobia, on organic molecules.
(C). Functional groups usually have little effect on the physical properties of a molecule they are bound to.
(D). Functional groups are not typically present in amino acids.
Correct Answer:  B.
(6) Which of the following term does NOT belong with others?
(A). Amino group
(B). Glycerol
(C). Fatty acid
(D). Saturated
Correct Answer:  D.
(7) Which of the following term does NOT belong with others?
(A). Nitrogenous base
(B). Phosphate group
(C). Deoxyribose
(D). Glycerol
Correct Answer:  D.
(8) Consider an atom of sodium with atomic number of 11 and an atomic weight 23. How many neutrons are in this atom?
(A). The number of neutrons in this atom cannot be determined from the given information.
(B). 12
(C). 23
(D). 11
Correct Answer:  B.
(9) Small organic molecules are joined to form macronucleus through_______ reactions.
 (A). condensation
(B). exothermic
(C). hydrolysis
(D). exchange
Correct Answer:  A.
(10) When an atom’s outer electron shell is only partially filled, the atom is considered_______.
(A). chemically stable
(B). charged
(C). chemically unstable
(D). uncharged
Correct Answer:  C.
(11) Organic molecules always contain ________.
(A). carbon, hydrogen, and oxygen
(B). carbon, hydrogen, and nitrogen
(C). carbon and oxygen
(D). carbon and hydrogen
Correct Answer:  D.
(12) Which characteristics of water accounts for its excellent solvent properties?
(A). Water can split into a hydrogen ion and a hydroxide ion.
(B). Water can form 8 hydrogen bonds with nearby water molecules.
(C). Water has a negatively charged portion and a positively charged portion.
(D). Water is made up of hydrogen and oxygen, which are covalently bonded together.
Correct Answer:  C.
(13) Which of the following chemical bond is the strongest?
(A). Covalent bonds
(B). Hydrophobic bonds
(C). Ionic bonds
(D). Hydrogen bonds
Correct Answer:  A.
(14) The pH of a solution reflects the hydrogen ion concentration. A change from pH 7 to pH 8 reflects ___________ change in hydrogen concentration.
(A). 10-fold
(B). 20-fold
(C). 100-fold
(D). 200-fold
Correct Answer:  A.
(15) Choose the mismatched pair.
(A). Ribonucleic acid; steroid
(B). Lipid; fatty acid
(C). Nucleic acid; nucleotide
(D). Polysaccharide, sugar
Correct Answer:  A.
(16) When placed in water, phospholipids will orient themselves________.
(A). with phosphates associated with water and lipids clustered away from the water
(B). with lipids associated with water and phosphates clustered away from the water
(C). into covalently bound polymers
(D). randomly
Correct Answer:  A.
(17) The ______ structure of proteins in the unique sequence of amino acids linked together.
(A). primary
(B). secondary
(C). tertiary
(D). quaternary
Correct Answer:  A.
(18)Which of the following is NOT a characteristic of RNA?
(A). RNA contains the pentose ribose.
(B). RNA is most often arranged in a double helix.
(C). RNA is usually single-stranded.
(D). RNA contains four nucleotide bases: A, U, C, and G.
Correct Answer:  C.
(19) You would expect a fluid with a pH of 10 to be called_______.
(A). an acid
(B). a base
(C). a buffer
(D). buffered water
Correct Answer:  B.
(20) Which of the following statements is true regarding carbohydrates?
(A). Carbohydrates are composed of carbon, hydrogen, oxygen, and nitrogen and are made up of peptide bonds linking amino acids.
(B). Carbohydrates are composed of a sugar, phosphate, and nucleotide base and are important in cell structure.
(C). Carbohydrates, such as glycogen and starch, are composed of carbon, hydrogen, and oxygen and function as important energy sources.
(D). Carbohydrates are made up of subunits called fatty acids and glycerol, which are made up of carbon, hydrogen, and oxygen and are important energy storage.
Correct Answer:  C.







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