The Biotic Environment - Effects on Health

HideShow resource information

BIOTIC ENVIRONMENT - EFFECTS ON HEALTH

  • physical activity
  • nutrition
  • stress management
  • mental stimulation
  • strong imune system
  • disease=disturbances homeostasis
    • exogenous
    • endogenous
    • chronic, acute

Immunity=ability of body - fight infection/foreign invaders by producing antibodies/killing infected cells

Immune system=maintaining homeostasis - recognising harmful from non-harmful organisms - appropriate response

Pathology=study essential nature - diseases+structural+functional changes produced by them

Antigens=substance, foreign to body - evokes immune response. alone/after forming complex - large molecule - capable binding with product, immune system.

  • identification structures+toxins, pathogens exhibit - cause harm
  • organs - immune system
    • tonsils+adenoids
    • lymphatic vessels+lymph nodes
    • thymus
    • spleen
    • peyer's patches
    • appendix
    • bone marrow
  • leukocytes=white blood cells
    • polymorphonuclear granulocytes - neutrophils, eosinophils, basophils
    • monocytes
    • lymphocytes
  • lymphatic system=lymph glands/nodes+lymphatic vessels
  • defense
    • skin
    • nonspecific immune response
    • specific immune response
  • skin
    • physical barrier=hard penetrate - indidestible keratin
    • chemical barrier=tears, sweat, saliva, mucous
  • nonspecific immune response=no matter what invader is
    • phagocytosis - macrophages
    • natural cell killers - kill invading+damaged cells
    • inflammation - release histamine by leukocytes
      • histamine released - increases blood flow
      • causes capillaries, leak. releases phagocytes+clotting factors - wound
      • phagocytes engulf bacteria, dead cells+cellular debris
      • platelets move out capillaries - seal wounded area
  • specific immune response
    • response - specific pathogen/antigen
    • creation, specific antibodies
  • antibodies
    • y shaped protein molecule
    • variable+constant regions
    • variable recognises antigens
    • heavy+light chains
    • produced - B lymphocytes
    • recognise antigens - bind to+ deactivate
  • immune response
    • antigen infects cells
    • macrophage ingests antigen+displays portion - surface
    • helper T cell recognises antigen - surface macrophage - become active
    • active helper T cell activates cytotoxic T cells+B cells
    • cytotoxic T cells divide - active cytotoxic T cells+memory T cells
    • active cytotoxic T cells kill infected cells
    • B cells divide - plasma cells+memory B cells
    • plasma cells produce antibodies - deactivate pathogen
    • memory T+memory B cells remain - speed up response, same antigen reappears
    • suppressor T cells stop immune response…

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all resources »