Chapter 16 Nonspecific Defenses of the Host
Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings B.E Pruitt & Jane J. Stein Chapter 16 Nonspecific Defenses of the Host
Nonspecific Defenses of the Host 。 Susceptibility Lack of resistance to a disease 。Resistance Ability to ward off disease Nonspecific resistance Defenses against any pathogen 。Specific resistance Immunity,resistance to a specific pathogen
Nonspecific Defenses of the Host • Susceptibility Lack of resistance to a disease • Resistance Ability to ward off disease • Nonspecific resistance Defenses against any pathogen • Specific resistance Immunity, resistance to a specific pathogen
Host Defenses Nonspecific Resistance Specific Resistance (Responses of the Immune System, Chapter 17) First line of defense Second line of defense Third line of defense 。Intact skin ·Phagocytic white Specialized lymphocytes: 。Mucous membranes blood cells B cells and T cells and their secretions 。Inflammation ·Antibodies Normal microbiota ·Fever Antimicrobial substances Figure 16.1
Host Defenses Figure 16.1
Mechanical Factors 。Skin Epidermis consists of tightly packed cells with Keratin,a protective protein
• Skin • Epidermis consists of tightly packed cells with • Keratin, a protective protein Mechanical Factors
Mechanical Factors 。Mucous membranes Ciliary escalator:Microbes trapped in mucus are transported away from the lungs Lacrimal apparatus:Washes eye Saliva:Washes microbes off 。Urine:Flows out Vaginal secretions:Flow out
• Mucous membranes • Ciliary escalator: Microbes trapped in mucus are transported away from the lungs • Lacrimal apparatus: Washes eye • Saliva: Washes microbes off • Urine: Flows out • Vaginal secretions: Flow out Mechanical Factors