Exam 1 Study Guide - Plagues

Exam 1 Study Guide - Plagues - Plagues: Increasing life...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Plagues: Increasing life expectancies , Major causes of death in the U.S. 1900 - TB, pneumonia, diarrhea 30%, Diphtheria, bronchitis 5% Heart disease, cancer, stroke 16%, Injuries 5%. 2000 - flu, Pneumonia 4% Diphtheria, bronchitis n.s. Heart disease, cancer, stroke 62%, Injuries 4%. Globally, 1/3 die of infectious disease, Difference between infectious and non-infectious disease? Infectious disease moves from person to person, or animal to animal; or plant to plant, more formally: transmitted from host to host, Non-infectious disease does not move from host to host. Germs: Germs are microbes, but most microbes aren’t germs, more than 99.9% of the microbes we encounter don’t cause disease - some are even beneficial, they’re everywhere - air, water, food, in the body, on the body, plants, animals, meteorites, most genetic material in us is microbial. Microbes in and on US: Many transient: they can’t grow and reproduce there, a few are resident: they grow and reproduce, most resident microbes are commensal, some mutualistic: help protect from disease-causing microbes. Salmonella: Disease typhoid, caused by bacterium (Salmonella typhi), Smeared on skin and on a glass slide, within 20 min., S. typhi was destroyed on skin, it grew on glass. Acne: Some resident microbes go from commensals to parasites, at puberty, hormone androgen stimulates sebaceous glands on face and back and they get blocked, Bacteria, like Proponibacterium acnes, grow and irritate the follicle area. Apocrine Glands: Other bacteria grow around secretions of the apocrine glands concentrated in underarms and genital region, don’t function until puberty, apocrine secretions are odorless until bacteria grow in them, purpose appears to be sexual attraction, Bacteria commensal or mutualistic? Bacteria in the Gut: “B. theta,” common inhabitant of human gut, Breaks down non-digestible plant material, Guides development of intestines, Signals for fat production, when food is gone, bacteria eats from host cells, effects mouse intestine. M. smithii, It scarfs up extra nutrients, Controls how much gets absorbed, May be a key to controlling weight, the gut is a community of bacteria. Disease: A harmful deviation from the normal structural or functional state of an organism, Signs or symptoms, Normal vs. diseased, May be infectious - transmitted and caused by an agent that reproduces in the host. 1967: Surgeon General announced “time to close the books on infectious disease and shift all national efforts to chronic diseases”. The Columbian Exchange: Periodontal disease – Bacteria, Form plaque, Biofilm, Bacteria produce toxins, kill soft tissue and bone. Exploration and settlement of the Americas began with Columbus in 1492, first recorded smallpox -Santo Domingo 1519, Spaniards arrived with smallpox, No Spaniards died, 1/3 to 1/2 of natives on Hispanola (Haiti & Dominican Rep.) died. Aztec fall: Original visit to Montezuma, Cortez left, Months later returned, Aztecs were suffering from smallpox, Attacked Mexico City in Aug. 1521, and was near defeat until death struck.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 4

Exam 1 Study Guide - Plagues - Plagues: Increasing life...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online