Name: 1) Which molecules are composed of units known as nucleotides? A) messenger RNA molecules, only B) transfer RNA molecules, only 2) The individuality of an organism is determined by the organism's A) DNA nucleotide sequence B) transfer RNA molecules 3) Examples of polymers which contain repeating units known as nucleotides are A) DNA and RNA B) hemoglobin and maltase C) DNA molecules, only D) both DNA and RNA molecules C) nitrogenous bases D) amino acids C) starch and glycogen D) fats and oils 7726-1 - Page 1 4) If the diagram represents a part of the process of protein synthesis, strand A would A) serve as a template for the synthesis of messenger RNA B) carry a code determined by the original DNA molecule from the nucleus to the cytoplasm C) pick up and transfer specific amino acids to the cytoplasm D) pick up and transfer nucleic acids to the nucleus Questions 5 and 6 refer to the following: The diagrams below represent nucleotides. 5) Which pair of nucleotides can be held together by weak hydrogen bonds? A) 2 and 3 B) 3 and 4 C) 4 and 2 D) 1 and 3 6) Which structure pairs with the adenine nucleotide during the formation of messenger RNA? A) 1 B) 2 C) 3 D) 4 7) Which substances are components of a DNA nucleotide? A) ribose, phosphate, and uracil B) thymine, deoxyribose, and phosphate C) phosphate, deoxyribose, and uracil D) phosphate, ribose, and adenine 8) Which nitrogenous bases tend to pair with each other in a double-stranded molecule of DNA? A) thymine-adenine B) cytosine-thymine C) guanine-adenine D) adenine-uracil
9) The molecule represented by the lettered symbols below is a 7726-1 - Page 2 A) base pair B) codon C) nucleotide D) triplet code 10) Which is the sugar component of a DNA nucleotide? A) deoxyribose B) adenine C) glucose D) phosphate 11) Which is the correct identification of the parts of the DNA nucleotide in the diagram below? A) A = phosphate, B = deoxyribose, C = thymine B) A = phosphate, B = ribose, C = uracil C) A = thymine, B = ribose, C = uracil D) A = uracil, B = deoxyribose, C = thymine 12) For the given phrase, choose the type of nucleic acid which is best described by the phrase. contains thymine instead of uracil A) DNA B) transfer RNA C) messenger RNA 13) For the given phrase, choose the type of molecule that is most closely associated with the phrase. contains the hereditary information passed on from generation to generation in humans A) transfer RNA, only B) messenger RNA, only Questions 14 through 17 refer to the following: The diagram below represents parts of two nucleic acid molecules. C) DNA, only D) messenger and transfer RNA, only 14) What is the normal nitrogenous base sequence in the segment of strand Y shown in the diagram? A) U-G-A-C B) T-G-U-C C) T-G-A-C D) T-A-A-C 15) At which location does the DNA molecule "unzip" during replication? A) 1 B) 2 C) 3 D) 4 16) If strand X serves as a template for the synthesis of strand Z, the base sequence of that fragment of strand Z shown is A) T-G-A-C B) A-C-T-G C) U-G-A-C D) A-C-U-G 17) Molecules represented by strand Z move from the nucleus of a cell to the cytoplasmic organelles known as A) mitochondria B) vacuoles C) centrioles D) ribosomes
18) The diagram below represents part of an organic molecule. 7726-1 - Page 3 The diagram represents a molecule of A) ATP B) DNA C) RNA D) FSH 19) The presence of DNA is important for cellular metabolic activities because DNA A) directly increases the solubility of nutrients B) directs the production of enzymes C) is the major component of cytoplasm D) is a structural component of cell walls 20) The replication of a double-stranded DNA molecule begins when the strands separate at the A) deoxyribose molecules B) hydrogen bonds C) ribose molecules D) phosphate bonds 21) During the replication of a DNA molecule, separation or "unzipping" of the DNA molecule will normally occur when hydrogen bonds are broken between A) thymine and thymine B) guanine and uracil C) adenine and cytosine D) cytosine and guanine 22) Which series is arranged in correct order according to decreasing size of structures? A) chromosome, nucleus, nitrogenous base, nucleotide, DNA B) nucleus, chromosome, DNA, nucleotide, nitrogenous base C) nucleotide, chromosome, nitrogenous base, nucleus, DNA D) DNA, nucleus, chromosome, nucleotide, nitrogenous base
23) The diagram below represents a part of a double-stranded DNA molecule. 7726-1 - Page 4 Which event must occur if a nucleus containing this molecule is to undergo normal mitosis? A) Weak hydrogen bonds at 5 break and the molecule replicates. B) Bonds at 2, 4, and 5 break and new nucleotides are synthesized. C) Bonds at 4 and 6 break and bases relocate. D) Weak hydrogen bonds at 7 break and new sequences of bases are formed. 24) Which two principal actions of genes insure homeostatic control of life processes and continuity of hereditary material? A) oxygen transport and cyclosis B) enzyme synthesis and replication 25) Which two bases are present in equal amounts in a double-stranded DNA molecule? A) adenine and thymine B) cytosine and thymine 26) DNA and RNA molecules are similar in that they both contain A) thymine B) nucleotides C) oxidation and hydrolysis D) pinocytosis and dehydration synthesis C) cytosine and uracil D) adenine and uracil C) deoxyribose sugars D) a double helix 27) For the given phrase, choose the type of nucleic acid which is best described by the phrase. genetic material responsible for the individuality of an organism, that is passed from parent to offspring A) transfer RNA B) DNA C) messenger RNA
7726-1 - Page 5 28) Which DNA strand below represents the complementary base sequence of a DNA strand represented in the diagram above? A) B) C) D) 29) The building blocks of both DNA and RNA molecules are known as A) polysaccharides B) hydrocarbons C) nucleotides D) amino acids