Which of the following is true of valves in veins?

A) They are associated with venous sinuses

B) They are most abundant in limbs

C) They contract to propel blood forward

D) They prevent blood pressure in veins from dipping below that of arteries

Name the enlarged swelling at the end of a that is a sensory structure

How is observant used by scientists

What types of gametes will a woman with type ab blood produce?

Which set of data most likely represents a tornado? A 300 mph wind speed; 3 minute duration; 2 miles wide; 12 mile path on the ground B 30 mph wind speed; 3 minute duration; 2 miles wide; 12 mile path on the ground C 80F ground air temperature;

What are genes and their role.

The steps in which solar wind is formed

What extends from earth core to earths crust

Which enzyme works on fats? amylase lipase peptidase trypsin

What body systems are used to type on a computer?

Small organisms have smaller cells than large organisms true or false