Skip to content
Human Body Study

Adaptive Immunity

The body’s slower, targeted defense — it learns each specific threat and remembers it.

The lymphatic and immune system A stylised body with the lymphatic organs placed at their anatomical positions, plus two concept panels for the functional arms — innate immunity (phagocytes eating pathogens) and adaptive immunity (lymphocytes and antibodies). Each label links to the article for that part. Innate immunity fast frontline: phagocytes ingest pathogens Adaptive immunity specific and remembered: lymphocytes and antibodies Tonsils Thymus Lymph nodes Spleen Lymphatic vessels Bone marrow Lymphatic organs and lymph vessels, plus the two arms of the immune response — schematic.

Key cells

Section titled “Key cells”
  • T lymphocytes (T cells) — attack infected cells directly and coordinate the response.
  • B lymphocytes (B cells) — produce antibodies that lock onto specific targets.

What it does

Section titled “What it does”
  • Mounts a precise response tailored to a particular microbe.
  • Forms memory cells, so a second encounter is met faster and harder — the basis of lasting immunity and of vaccination.

Key idea

Section titled “Key idea”

Adaptive immunity is slow on first exposure but never forgets; that memory is what makes a disease survived once, or a vaccine given once, protective for years.