The multicellular transport system in mammals relies on blood, which consists of various specialized components working together.
Complete the table by identifying the missing blood components and their main physiological functions.
| Component of Blood | Primary Physiological Function |
|---|---|
| Erythrocytes (red blood cells) | |
| Synthesis and secretion of antibodies | |
| Thrombocytes (platelets) | |
| Transport of dissolved carbon dioxide, urea, and hormones |
When a person is exposed to the varicella-zoster virus (the pathogen causing chickenpox) for a second time, their immune system responds much more effectively than during the first exposure.
Describe how memory cells function to protect the body upon re-infection with this same pathogen.
55 exam-style questions on Edexcel IGCSE Biology Transport. Each one has a worked solution and a mark scheme showing where the marks go.