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Stress and Immune System Animation

By: Administrator, Views: 10923

How stress and the immune system are linked. Immune response declines with age, limiting body's ability to identify and fight foreign substances. Loss of thymus cortex leads to reduced production of T lymphocytes, including T cells, NK cells, B lymphocytes. Frequency and severity of infectio...

Role of complement proteins

By: HWC, Views: 7473

• Non-specific and specific defense mechanisms work through the functions of complement proteins. • As soon as pathogens penetrate the physical barrier of the skin, other resistance mechanisms begin. • Cells, such as macrophages, phagocytize pathogens. • These cells increase exposu...

Cortisol (protein catabolism, gluconeogenesis, vasoconstriction & anti-inflammation)

By: HWC, Views: 7300

• Stressors stimulate production of hypothalamic releasing hormones, corticotropin releasing hormone, hormone (CRH) and adrenocorticotropic hormone (ACTH) stimulate. • These hormones promote increased production of 1 cortisol from the zona fasciculata cells of the adrenal cortex. • Cort...

Barriers - eye structures, digestive mucosa, respiratory mucosa & genitourinary mucosa

By: HWC, Views: 8015

• Eyebrows, eyelids, eyelashes and conjunctiva serve to trap microbes preventing their invasion. • Tearing (lacrimation) is a protective mechanism that washes away microbes that attempt to enter the eyes. • Salts, mucus, and lysozymes in tears neutralize substances and bacteria. â€...

Types of antimicrobial substances (interferons & complement protein)

By: HWC, Views: 7746

• Found in blood and interstitial fluids. • Discourage microbial growth. • Include interferon and complement proteins. • Produced and released by virus-infected lymphocytes. • Enter new cells and inhibit viral replication. • Act against a large variety of viruses (non-speci...

Primary and secondary response to infection

By: HWC, Views: 7470

• Pathogens enter the body by penetrating the non-specific barriers in the skin and mucus membranes. • Pathogens first encounter macrophages and natural killer cells that carry out phagocytosis and cytolysis respectively. • A pathogen's first encounter with the immune system can promo...

Cellular defenses (natural killer cells, phagocyte types & process of phagocytosis)

By: HWC, Views: 7458

• Lymphocytes that rapidly defend against abnormal (cancer) or virus-infected cells. • Found in blood, spleen, lymph nodes, and red bone marrow. • Lack receptors for binding with specific antigens. • Act upon cells displaying abnormal MHC antigens. • NK cells destroy cells in ...