Immune System Response Overview

Immune Response

• Pathogens invade the body, triggering lymphocytes to produce antibodies for destruction.
• Each pathogen needs a specific antibody.
• Initial infection takes time for the immune system to identify the correct lymphocyte for antibody production.
• Pathogens replicate and cause illness during this initial response time.
• Memory cells form after initial infection, recognizing the pathogen on re-exposure.
• Memory cells accelerate the immune response by immediately producing antibodies upon subsequent exposure.
• Memory cells provide active immunity.

Active vs. Passive Immunity

• Active immunity results from the body producing its own antibodies to combat pathogens.
• Passive immunity involves receiving antibodies from an external source (e.g., breast milk, injections).
• Passive immunity is temporary because the antibodies are not sustained indefinitely.

Active Immunity

• Acquired through infection or vaccination.
• Vaccinations expose individuals to weakened or inactive forms of pathogens, inducing memory cell production without causing illness.
• Vaccination results in active immunity.

Passive Immunity

• Obtained through antibody injections or breastfeeding.
• Rabies treatment often involves injecting antibodies directly into the body.
• Breast milk provides antibodies to infants.

Memory Cells

• Produced during the initial infection.
• A specific type of lymphocyte.
• Memory cells enable faster responses to subsequent encounters with the same pathogen.

Vaccination

• Weakened or inactive pathogens are introduced into the body during vaccination.
• This process stimulates the immune system to develop memory cells, fostering active immunity without causing disease.
• Vaccinations can be administered via injection or orally.

Exam Help

• Lymphocytes generate memory cells during the initial infection, offering active immunity.
• Memory cells facilitate a quicker immune response to a subsequent infection.