5.2: Phagocytosis

Question 1

What are the two different types of White Blood Cells

Answer 1

Phagocytes - Involved in Phagocytosis

Lymphocytes - (B and T) Involved in the Cell-Mediated Response and the Humoral Response

Question 2

Process of Phagocytosis

Answer 2

1. Chemical products of a pathogen or dead cell attract a Phagocyte
2. Phagocytes contain cell-surface receptors on their membrane, these recognise and attach to the chemicals on the surface of the pathogen
3. The phagocyte engulf the pathogen to form a vesicle, known as a Phagosome
4. Lysosomes move towards the Phagosome and secrete Lysozymes into the Pathogen, hydrolysing its cell wall.
5. The hydrolysed cell-contents are taken up by the cytoplasm of the Phagocyte.

Question 3

First line of defence

Answer 3

Physical or chemical barriers

Question 4

Second line of defence

Answer 4

White Blood Cells

Phagocytes & Lymphocytes