Defence Mechanisms

Section 1: Understanding Defence Mechanisms

  • Defence mechanisms are the strategies employed by the body to fight against threats such as pathogens or toxins.
  • These mechanisms are complex and multi-layered, including both physical barriers and specialised cells.
  • They can be divided into two categories: innate (nonspecific) and adaptive (specific) immunity.

Section 2: Innate Immune Responses

  • Physical barriers, like the skin and mucous membranes, block pathogens from entering the body.
  • Chemical barriers, such as stomach acid or enzymes in saliva and tears, destroy pathogens before they can cause harm.
  • Cellular defences, like phagocytes, destroy pathogens through processes like phagocytosis where the pathogen is engulfed and digested.

Section 3: Adaptive Immune Responses

  • The adaptive immune system becomes activated upon exposure to pathogens and typically takes longer to respond than the innate system.
  • Lymphocytes, including B-cells and T-cells, play pivotal roles in adaptive immunity.
  • B-cells produce antibodies that bind to specific pathogens, while T-cells destroy infected body cells.

Section 4: Understanding the Role of Vaccines

  • Vaccines introduce a harmless form of a pathogen into the body to stimulate an immune response without causing disease.
  • This enables the adaptive immune system to respond faster and more effectively if it encounters the same pathogen again.
  • Vaccines provide crucial herd immunity, protecting even those who can’t be vaccinated by reducing the general presence of the disease.

Section 5: Maintaining a Healthy Immune System

  • A balanced diet rich in fruits, vegetables, and lean proteins can provide vitamins and minerals needed for a healthy immune system.
  • Regular exercise and a healthy lifestyle can also play a role in maintaining an optimally functioning immune system.
  • Avoiding toxins such as tobacco, alcohol or excessive stress, can also enhance your immune health.

Remember, having a comprehensive underpinning of these concepts will be important to successfully address questions on this topic. These bullet points serve as a starting point for deeper study.