5.4 Host-Microbe Interactions

Question 1

Bening

Answer 1

Most organisms are benign, meaning they pose no harm

Question 2

Microorganisms

Answer 2

• > few contribute to health - fewer pose direct threat to health
• > Usuallys found associated with human tissue - commensal microbes (microbial flora)
• > humans are colonised by specific microorganisms at birth (from mother)

Question 3

Microbial flora

Answer 3

found on skin and in gut (person-specific composition) - Microbiome

Question 4

General Process of Pathogenesis

Answer 4

Pathogens use various strategies to cause disease but often the general process of pathogenesis is similar

Exposure to pathogen

• > Adherence for skin or mucosa
• > Invasion through epithelium
• > colonization and growth production of virulence factors

=> further exposure at local sites -> exposure to pathogen

1. -> Toxicity : toxins effects are local or systemic
2. -> Invasiveness : further growth at original and distant sidts

=> Further exposure -> exposure to pathogens

-> Tissue damage, disease