{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Biology 6 Chapter 14

Biology 6 Chapter 14 - Biology 6 Chapter 14 Environmental...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Biology 6 Chapter 14 Environmental Hazards and Human Health o Acquired immune deficiency syndrome caused by infection with human immunodeficiency virus is a serious and rapidly growing health threat o Virus itself is not deadly, but it cripples the immune system and leaves the body susceptible to infections such as tuberculosis and rare forms of cancer such as Kaposi’s sarcoma o Virus is transmitted from one person to another through unsafe sex, sharing of needles by drug users, infected mothers who pass the virus on to their offspring before or during birth, and exposure to infected blood. o Each year about 16,000 people died of AIDS-related diseases in United States. 3 million worldwide o Risk: probability of suffering harm from a hazard that can cause injury, disease, death, economic loss, or environmental damage o 4 types of Hazards: 1. Biological Hazards : more than 1,400 pathogens (bacteria, viruses, parasites, protozoa, and fungi) that can infect humans 2. Chemical Hazards : harmful chemicals in air, water, soil, and food 3. Physical Hazards : fire, earthquakes, volcanic eruptions, floods, and storms 4. Cultural Hazards : unsafe working conditions, unsafe highways, criminal assault, and poverty o Nontransmissible disease : caused by something other than living organisms and does not spread from one person to another; tend to develop slowly and have multiple causes ex. Most cancers, most cardiovascular disorders, asthma, emphysema, and malnutrition o Transmissible disease : an infectious disease caused by a pathogen and can be spread among people o Epidemic: large- scale outbreak of an infectious disease in an area or country o Pandemic: global epidemic o Problems with antibiotics : many disease carrying bacteria have developed genetic immunity to widely used antibiotics ; many disease transmitting species of insects such as mosquitoes have become immune to widely used pesticides that once helped control their populations; bacteria’s high reproductive rate allows organisms to become genetically resistant to an increasing number of antibiotics through natural selection; other factors that contribute to genetic resistance are human travel around globe, international trade; overuse of antibiotics by doctors; at least half of all antibiotics are prescribed unnecessarily; every major disease-causing bacterium now has strains that resist at least one
Background image of page 1

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

View Full Document Right Arrow Icon
o 3 most widespread and dangerous viruses: influenza(flu), human immunodeficiency virus (HIV), and hepatitis B virus (HBV) 1.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 4

Biology 6 Chapter 14 - Biology 6 Chapter 14 Environmental...

This preview shows document pages 1 - 3. Sign up to view the full document.

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