| Date | May 2017 | Marks available | 1 | Reference code | 17M.3.SL.TZ2.20 |
| Level | Standard level | Paper | Paper 3 | Time zone | Time zone 2 |
| Command term | State | Question number | 20 | Adapted from | N/A |
Question
Rats were injected with antibodies that induced phagocytosis of red blood cells (erythrocytes) leading to their breakdown. The graph shows the percentage of intact and partially digested erythrocytes in cells of the liver as observed under the microscope.
State the name of the cells that perform the breakdown of erythrocytes in the liver.
Describe the breakdown of erythrocytes by liver cells.
Outline the fate of the iron from the erythrocytes.
Markscheme
Kupffer
a. cells phagocytose/engulf the erythrocytes
b. hemoglobin is split into heme group and globins
OR
heme is removed from hemoglobin
c. globins broken down/hydrolyzed to peptides/amino acids
d. heme group separated into iron and bilirubin
a. carried to bone marrow
b. used in the production of hemoglobin/new erythrocytes
