---

---

Select your answer:
         

Next Quiz >

Topics:

Teeth & Microbes Human Circulatory System Ecology Skeletal System Tissues Tenses Healthcare Careers Nephrology (Hemodialysis) Meiosis and intro to Genetics Protein Synthesis Enzymes Liveability Human Genome and Bioethics Review Public Health and Genetic Disease The Ear Who am Eye?

Other quiz:

Medical Careers › View

What does “ST” stand for?

A. Normal vision

B. Health care worker who examines and tests eyes

C. Health care worker who assists surgeons

D. Health care worker who often helps doctors in the office

---

Circulation and Excretion › View

Water across the gills of fish and the blood in the gills does in opposite direction enhancing the diffusion of oxygen from the water into the blood. What is this flow in the opposite direction called?

A. undirectional flow

B. countercurrent exchange

C. atriventricular exchange

---