1 Multiple choice questions (numbers in brackets indicate the number of correct answers) February 1, 2013 1. Ribose is found in Nucleic acids Proteins Lipids RNA DNA (2) 2. Most RNA in cells is transfer RNA messenger RNA ribosomal RNA micro RNA small nuclear RNA (1 3. Optical mapping Uses restriction enzymes Is normally done with metaphase chromosomes Determines the position of restriction sites in a DNA molecule Uses a fluorescent dye Is a technique used in genetic mapping (3) 4. Radiation hybrids Are human cell lines Can hold large pieces of chromosomal DNA Are rodent cell lines Are produced by irradiation with UV light Have been used in mapping the yeast genome (2) 5. Physical mapping Requires large numbers of organisms Utilizes genomic libraries Is less accurate than genetic mapping Detects polymorphic DNA sequences Uses restriction fragment polymorphisms (RFLPs) (1) 6. Hydrogen bonds are covalent bonds stabilize the DNA double helix stabilize protein structures form between two electronegative atoms form between adenin and guanine have a bond energy of 20-30 kcal mol -1 (2)
2 7. An EST (Expressed Sequence Tag) Is a protein sequence Is an RNA sequence Is a DNA sequence Is used to delineate regulatory sequence elements Is used in genetic mapping Consists only of exon sequences Can often be detected by histochemical assays (2) 8. An STS (Sequence Tagged Site) Is a protein sequence Is an RNA sequence Is a DNA sequence Is used in genetic mapping (1) 9. Proteomes Occur in all living cells Consist of protein-coding genes Are characterized by Southern analysis Differ in different cell types Are analyzed by agarose gel electrophoresis (2) 10. cdna Is made from ribosomal RNA Is made from trna Is made from mrna Contains only introns Contains only exons Is single-stranded (2) 11. The genetic code is a triplet code consists of 62 codons has three stop codons is used in the process of transcription specifies 25 amino acids is degenerate (3) 12. Restriction fragment length polymorphisms (RFLPs) Are used to determine the position of restriction sites in a genome Are used in physical mapping Are used in genetic mapping Usually occur as multiple (more than 2) alleles in a genome (1)
3 13. PCR is used for reverse transcribing RNA into DNA digesting proteins digesting DNA copying plasmids amplifying DNA amplifying proteins (1) 14. β-sheets are stabilized by hydrophobic bonds ionic bonds hydrogen bonds covalent bonds all of the above none of the above (1) 15. Transformation converts DNA into RNA converts RNA into proteins joins two DNA fragments cuts DNA into fragments introduces DNA into cells removes genomes from cells is used in cloning of DNA (2) 16. Nucleic acids were first isolated in the 17th century 18th century 19th century 20th century (1) 17. The following are not components of DNA Pyridines Purines Sulfate Phosphate Deoxyribose (2) 18. The secondary structure of proteins is stabilized by Hydrophobic interactions Ionic bonds Hydrogen bonds Disulfide bonds (1) 19. The major form of DNA in cells is A-DNA B-DNA C-DNA Z-DNA (1)
4 20. The shotgun method is used in analyzing transcriptomes is used in bacterial genome sequencing projects is more accurate than the clone contig method is normally used with large genomes takes more time than other genome sequencing approaches (1) 21. Restriction endonucleases are located in the nucleus of cells degrade DNA completely bind to DNA are enzymes are proteins were discovered in the 1980s (3) 22. Cloning vectors are always plasmids contain an origin of replication have an average size of 20 kilobase pairs (kb) are always circular molecules contain always an antibiotics resistance gene (1) 23. Z-DNA Winds to the left Has a wider diameter than A and B-DNA Does not naturally occur in cells Has been studied extensively by Watson and Crick (1) 24. DNA polymerases join DNA fragments replicate RNA replicate DNA synthesize DNA in 5 ->3 direction synthesize DNA in 3 ->5 direction require a primer to function require nucleotides to function require ATP (4) 25. DNA is a positively charged molecule at neutral ph contains phosphate is always double-stranded has a width of around 2 µm is stabilized by base stacking (2)
5 26. Simple sequence length polymorphisms can occur in minisatellites can occur in microsatellites can occur in satellite DNA are used in genetic and physical mapping can be typed by oligonucleotide hybridization (3) 27. Bacteriophage lambda is a virus infects several species of bacteria has a genome of about 20,000 bp has three types of infection cycles has a head-and-tail shape (2) 28. The human nuclear genome Is about 2 billion bp in size Is split into 24 chromosomes Contains about 50,000 genes Is the largest genome known to date (1) 29. DNA ligases Catalyze the formation of ß-glycosidic bonds Catalyze the formation of phosphodiester bonds Play a role in the process of transcription in cells Play a role in the process of translation in cells Require energy to function Are found in all living cells (3) 30. Reverse transcriptases Are DNA polymerases Are RNA polymerases Use DNA as template Use RNA as template Are viral enzymes Are essential enzymes in all eukaryotic cells (3) Total number of correct answers: 55