Biology A-Level
Open versus closed systems
What Open versus closed systems means in Biology A-Level, as defined for OCR.
Definition of Open versus closed systems
Check what you remember
Read the wording for your board, then hide it and explain Open versus closed systems in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: OCR
In a closed system blood is confined to vessels, whereas in an open system blood leaves vessels and bathes the tissues in a haemocoel.
Topics that use Open versus closed systems
- Transport in animals (OCR A-Level)
Related terms
- Association and dissociation of oxygen
- Carbon dioxide transport forms
- Control of blood distribution by arterioles
- cooperative binding
- double circulation
- Exchange at capillaries and return of blood in veins
- Heart anatomy
- Heart rate and rhythm interpretation
Using Open versus closed systems in the exam
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