DP Biology (last assessment 2024)
Question 23M.3.SL.TZ2.18
Date | May 2023 | Marks available | [Maximum mark: 3] | Reference code | 23M.3.SL.TZ2.18 |
Level | SL | Paper | 3 | Time zone | TZ2 |
Command term | Describe | Question number | 18 | Adapted from | N/A |
18.
[Maximum mark: 3]
23M.3.SL.TZ2.18
The liver has a dual blood supply. The diagram shows some of the basic structures of liver tissue.
Describe the flow of blood through the liver.
[3]
Markscheme
- blood from the (hepatic) portal vein (from the intestine);
- blood (from portal vein) flows through the sinusoids;
- blood enters from hepatic artery (from heart/aorta);
- blood flows through capillaries;
- blood leaves through the hepatic vein;
Examiners report
Blood supply to liver was well known although a few mixed-up artery and vein. Weaker students simply repeated information in the question. The three main vessels were identified by most candidates. There was some discussion of sinusoids and capillaries, but they were not mentioned in many responses.

