1. James Watson and Francis Crick discovered the double helix structure of DNA in 1953. 2. Gregor Mendel was the first to study heredity through his experiments breeding pea plants in the mid-19th century. He used the method of crossbreeding. 3. The discovery of the structure of DNA provided an explanation for how traits are inherited and passed down from generation to generation.

1. UnderstandingDNA Name:______________________________
1. Whichtwo scientistsdiscoveredthe structure of DNA?
2. Whenhumansbreedplantsandanimalsfora trait, itis called
a. Selectiveinheritance
b. Selectivegenetics
c. Selectivebreeding
3. Before the discoveryof DNA,peopleknew thatsome _____________________________ can be
passeddowninfamilies.
4. Who wasthe firstpersontostudyheredity?
5. Whichmethoddidhe use to studyheredityinplants?
a. Pollination
b. Crossbreeding
c. Bioengineering
6. The two differentfactorsstudieswerenamed________________________________, or always
expressed,and______________________ or sometimesexpressed.
7. What methodwasusedto firstsee DNA?
8. Whichtechniciantookthe firstimagesthatrevealedthe structure of DNA?
9. Why didFranklinnotreceive the NobelPrize?

2. 10. Medical technologydevelopedtotestforwhichhereditarydisease?
a. Crohn’sdisease
b. Muscular dystrophy
c. Alzheimer’sdisease
11. Whichis a methodof replacingfaultygenes?
a. Hereditaryconditioning
b. Prenatal imaging
c. Geneticengineering
12. What was the purpose of the humangenome project?
13. Movingskinfromone area of the bodyto anotheriscalled
a. Rhinoplasty
b. Grafting
c. Lasik
14. Introducinghealthygenesintocellsaffectedbydisease is
a. Gene therapy
b. Bioengineering
c. Cysticfibrosis
15. What isthe purpose of geneticallyengineeringfood?