Select your answer:
Topics:
Respiratory System Biomedical Cell Theory and Cell Organelles Pathophysiology of Injuries and Diseases Respiration, Immune System, Blood Cells Functional Anatomy in Track & Field Teeths Communicable Diseases and Immune Response (OCR) Central Nervous System Virus Circulation and Excretion Joints in our Body Skeletal System Therapeutic Services Roots VirusesOther quiz:
Health and Diseases › ViewInfectious diseases are diseases caused by an organism such as a virus or a bacterium, which is called a:
A. pathogen
B. toxicant
C. pandemic
D. carcinogen
Human Eye and Colorful World › View
The air layer of atmosphere whose temperature is less then the hot layer behave as optically
A. denser medium
B. rarer medium
C. inactive medium
D. either denser or rarer medium