Defense Mech

Question 1

What are antigens?

Answer 1

Molecules that can generate an immune response when detected by the body.

Question 2

What are the two forms of responses by the body?

Answer 2

• Cell mediated responses, T lymphocytes.

* Humoral responses, B lymphocytes

Question 3

What types of lymphocytes are involved in humoral?

Answer 3

B lymphocytes

Question 4

What types of lymphocytes are involved in humoral?

Answer 4

B lymphocytes

Question 5

What is a phagocyte?

Answer 5

A type of white blood cell that carries out phagocytosis, they are the first cells to respond to an immune system trigger inside the body.

Question 6

Where are phagocytes found?

Answer 6

• Blood

* Tissues

Question 7

What are the two types of white blood cell?

Answer 7

• Phagocytes

* Lymphocytes

Question 8

What do phagocytes do?

Answer 8

Ingest and destroy pathogens in a process called phagocytosis before they can cause harm.

Question 9

What is the purpose of lymphocytes?

Answer 9

Involved in immune responses.

Question 10

What is the process of phagocytosis?

Answer 10

• Chemical products of pathogens or dead, damaged and abnormal cells act as attractants, causing phagocytes to move towards the pathogen.
• Phagocytes have receptors on their cell surface membrane that act recognise and attach to chemicals on the surface of the pathogen.
• They engulf the pathogen to form a vesicle known as a phagosome.
• Lysosomes move towards the vesicle and fuse with it.
• Enzymes called lysozymes are present within the lysosomes, these lysozymes destroy ingested bacteria by hydrolysis of their cell walls.
• Soluble products from the breakdown of the pathogen are absorbed into the cytoplasm of the phagocyte.