Lecture 4

Question 1

What is immunity?

Answer 1

The body’s ability to protect itself by resisting or eliminating potentially harmful foreign invaders (e.g., bacteria and viruses) or abnormal cells (e.g., cancer cells) that are foreign to normal self.

This is where the immune response comes from.

Question 2

What are immune system activities?

Answer 2

Defends against invading pathogens.

Removes worn-out cells and tissue damaged by trauma.

Identifies and destroys abnormal or mutant cells that have originated in the body (Immune surveillance).

Mounts an appropriate immune response that leads either to allergies or to autoimmune disease.

Smallpox is officially eradicated.