Ch 20 Mini-Review

1. Ch 20 Mini-Review

2. Vocabulary terms Gene expression refers to the transcription and translation of a gene or set of genes. Gene regulation refers to the control of gene expression.

3. Hybridization is the process by which two complementary strands of nucleic acid base pair to one another to form a duplex. If two strands of nucleic acid are not complementary, they will not hybridize to form a duplex. Gene knockouts are experiments in which a gene is deleted from the genome of an organism. Knockouts are used to gain information about the function of a gene.

4. 1) Why is this a restriction enzyme site? • Restriction enzymes bind to special hydrogen bond sites • Restriction enzymes cut at GAATTC • Restriction enzymes cut at CTTAAG • Restriction enzymes recognize specific reverse order sequences

5. 2) What are “sticky ends?” • Pieces of DNA that are run through a gel in order to give a unique banding pattern • Single-stranded DNA ends that are available to hydrogen bond to a complimentary single strand • DNA bases that are added to a PCR machine so that multiple exact copies of a DNA sequence can be produced • Segments of DNA that act as a probe in order to diagnose a genetic condition

6. 3) What is this called? plasmid • RFLP (restriction length polymorphism) • PCR (polymerase chain reaction) • Clone • Recombinant DNA Human gene

7. 4) What is the purpose of PCR? • To make billions of identical copies of a specific DNA segment • To separate out DNA segments by size • To help make medical products such as insulin • To help cure diseases such as Cystic Fibrosis

8. 5) Why does PCR lead to a specific DNA segment? • PCR always leads to the same DNA sequence • DNA replication makes identical copies of itself • The primers are made to bracket a certain nucleotide sequence • All of the above are true

9. 6) In order to run a PCR’d sample of DNA through a gel, what must be done to the DNA first? • It must be heat-treated. • It must be cut with restriction enzymes (endonucleases) • It must be stained. • Both 1 & 2

10. 7) What is the basis for DNA movement in gel electrophoresis? • DNA has a (+) charge so it moves towards a (-) electrical terminal • DNA has a (+) charge so it moves towards a (+) electrical terminal • DNA has a (-) charge so it moves towards a (+) electrical terminal • DNA has a (-) charge so it moves towards a (-) electrical terminal

11. 8) Which fragment of DNA is the smallest in this gel picture? A B • A • B • C • D C D

12. 9) What is the first step in making single-stranded cDNA? • Use Reverse transcriptase • Use DNA polymerase • Wash over microarray • Isolate mRNA

13. 10) Cells extracted from a man with prostate cancer were made with yellow fluorescing nucleotides & cells extracted from a man without prostate cancer were made with blue fluorescing nucleotides. Green indicates both yellow & blue. Which gene(s) exhibit no gene expression? • 1, 3 • 2, 5, 9, 10 • 4, 7 • 6, 8 1 2 3 4 5 6 7 8 9 10

14. 11) Yellow: from cancer cell; Blue: cell w/o cancer Which gene(s) exhibit a mutation? 1 2 3 4 5 • 1, 3 • 6, 8 • 1, 3, 6, 8 • 4, 7 6 7 8 9 10

15. 12) Which gene has a higher level of expression, 1 or 3? 1 2 3 4 5 • 1 • 3 • Both are the same 6 7 8 9 10

16. 13) Which of the following is NOT an application of biotechnology? • Agricultural products such as transgenic rice making beta-carotene • Pharmaceutical products such as insulin • Environmental uses; cleaning up oil spills • Medical uses; to help parents have children with specific traits • Medical uses; to help diagnose some diseases

17. 14) Which of the following can be a biotechnology vector? • Plasmid • Virus • E. coli • A and B • A, B, & C

18. 15) What is a DNA fingerprint? • All of a person’s DNA cut in to different size fragments & run through a gel • Many (6-8) segments of a person’s DNA cut in to different size fragments & run through a gel • 1 segment of a person’s DNA cut in to different size fragments & run through a gel • 1 entire chromosome cut in to different size fragments & run through a gel

19. 16) Is either of these men the father of the child? (Focus on just mother, child, & alleged father) • A is the father • B is the father • Neither is the father

20. 17) List steps of PCR 1)Heat to separate DNA strands (95ºC); 2) Cool to allow primers to bind (55ºC); 3) Heat slightly so that DNA polymerase extends the 3’ end of each primer (72ºC) 4) Repeat steps #1-3 many times!!!

21. 18) What does reverse transcriptase do? • Takes mRNA to cDNA Reverse transcription)

22. 19) List 3 protein products produced by pharmaceutical companies today. • human insulin (diabetes med.) • Human growth hormone (used for certain types of dwarfism) • TPA - tissue plasminogen activator (dissolves blood clots) • Working on drug to block HIV infection (virus binds to drug instead of WBC) • Produce vaccines

23. 20) List 3 ways agriculture is using modern day biotechnology.  Agricultural uses (“Pharm” Animals and Plants) 1)livestock -bGH (bovine growth hormone) to enhance milk production -sheep that carry a gene for human blood protein -genes that cause devp’t of larger muscles in cattle -salmon that grow larger due to a modified growth hormone 2) genetically engineered plants - insecticide/herbicide resistance - delaying of ripening/resistance to spoiling - transgenic rice that contain beta-carotene to solve the vitamin A deficiency in poorer countries