Help! Final Exam for Alters and Alters

Question 12 of 60   1.667 Points
Which of the following best describes a closed circulatory system?

 

   A. Oxygen is delivered through hemolymph.   
 

   B. oxygen is carried via a tracheal system.    
 

   C. It is a system prevalent in arthropods.   
 

   D. Blood is confined within blood vessels.   
 

   E. Circulation is highly dependent upon animal body movements   
Question 13 of 60   1.667 Points
Ailis has varicose veins in her legs. What is the cause?

 

   A. Failed valves.   
 

   B. Failed capillary beds.   
 

   C. Failing heart.   
 

   D. Failed arterioles.