Question

Differentiate between open and closed circulation with reference to:

1. blood pressure
2. exchange of material

Answer 1

Point of distinction	Open circulation	Closed circulation
(i) Blood pressure	Blood flows with low pressure.	Blood flows under high pressure.
(ii) Exchange of materials	The exchange of materials occurs directly between blood and cells or tissues of the body.	The exchange of materials takes place between blood and body tissues through an intermediate fluid called lymph.