It develops in the bone marrow and matures from a monocyte. It has numerous lysosomes containing hydrolytic enzymes.
It forms and matures in the bone marrow. It has a lobed nucleus and can ingest microorganisms by endocytosis.
After activation, it differentiates into a cell that releases a chemical, which makes other cells lyse (burst). It has a large, spherical nucleus.
It is produced as part of a primary immune response and remains in the body. When activated, it can produce antibodies in a secondary immune response.
Define what is meant by the term disease.
State exactly which type of white blood cell matches each of the descriptions given in (i) to (iv).
In 1980, it was declared that the highly infectious viral disease smallpox had been eradicated. This was largely the result of a worldwide vaccination programme organised by the World Health Organization (WHO). Attempts have been made to control other diseases, including measles, sickle cell anaemia and cholera, but with none of the same success achieved for smallpox.
Describe two characteristics of the vaccine that contributed to the success of the smallpox eradication programme.
Discuss why vaccination has not succeeded in eradicating cholera and sickle cell anaemia.