1
									2
												3
						4
															5
					6
				7
																				8
												9
													10									11
								12
			13																					14
																										15		16
		17
18
							19
20
														21
			22
																				23

Across 3. interpretation of the genetic code and its role in protein synthesis 4. discovery of the citric acid cycle (Krebs cycle) 5. discovery that x-rays produce mutations 7. discoveries concerning genetic control of enzyme and virus synthesis 9. developerment of computed axial tomography (CAT scans) 10. discovery of penicillin 13. discovery of prions, a type of infectious protein such as the one that cause mad cow 17. discoveries on the cellular mechanisms of action of hormones 18. discovery of the functional specialization of the cerebral hemispheres (right brain, left brain) 19. discovery of role of chromosomes in heredity 20. discoveries about structure of the nervous system 21. discovery of the ultrastructure of the cell, and discovery of the function of many of the newly-discovered organelles that they revealed 22. important discoveries and investigations on tuberculosis 23. discoveries concerning yellow fever (malaria) and how to combat it

Down 1. discovery of mobile genetic elements, sometimes referred to as "jumping genes" 2. discovery of organizer effect in embryological development 6. discoverery of Helicobacter pylori, and the role of this bacterium in peptic ulcer disease 8. development of in vitro fertilization treatment for infertile couples 11. discovery of insulin 12. discovery of nitric oxide as a signalling molecule in the cardiovascular system 14. discovery of human papilloma viruses that cause cervical cancer 15. discovery of the human immunodeficiency virus (along with others) 16. discovery that genes act by regulating definite chemical events (along with Edward Tatum)