30Heart CirculationHard1 mark
The diagram shows an experiment that took place in 1940 to revive an animal.
Air is bubbled through the reservoir to oxygenate the blood. The tubes enter and leave the neck of the animal.
Which characteristics of mammalian circulation does the diagram represent?
| closed system | heart | double circulation | |
|---|---|---|---|
| A | ✗ | ✗ | ✗ |
| B | ✗ | ✓ | ✗ |
| C | ✓ | ✓ | ✗ |
| D | ✓ | ✓ | ✓ |
Key: a tick (✓) shows the diagram represents this characteristic; a cross (✗) shows it does not.