The table shows blood leaving and returning to the heart.
Table
| Vessel | Direction relative to heart | Oxygen concentration |
|---|---|---|
| X | away | low |
| Y | towards | high |
Which comparison of the vessels is correct?
X is a vein with a thicker wall than artery Y.
X is an artery with a thinner wall than vein Y.
X is a vein with a thinner wall than artery Y.
X is an artery with a thicker wall than vein Y.
42 exam-style questions on Edexcel GCSE Biology 8.2 Blood and circulation, covering 8.2.1 Structure and function of the blood, 8.2.2 Structure of blood vessels, 8.2.3 Structure of the heart and circulatory system, and 8.2.4 Cardiac output. Each one has a worked solution and a mark scheme showing where the marks go.