PHLT 304 Exam 1 Questions & Answers Solved 100%

Public Health Triad - Answer -the triad consists of an external agent, a susceptible host, and an environment that brings the host and agent together. -disease results from the interaction between the agent and the susceptible host in an environment that supports transmission of the agent from a source to that host. What is one health and how is it important to public health? - Answer -One Health is a collaborative, trans-disciplinary approach to achieving optimal health for people and other organisms in the environment -The health of people is connected to the health of animals, plants and the shared environment - 6 out of 10 infectious diseases in human are spread from animals What are ecosystem services? - Answer - Functions of natural systems that give humans value for free -Vultures eat dead animals, reducing food sources for scavengers that could carry zoonotic disease What is eutrophication and why is it a problem? - Answer - water body receives excessive nutrients (esp. N,P) -overgrowth of algae -algae die and decompose, depleting oxygen in the water - lack of oxygen kills aquatic animals How can animal borne diseases affect humans? - Answer Lyme disease caused by ticks What are the problems caused by climate change? - Answer -Food and water scarcity -Changes in geographic distribution or prevalence of disease (dengue, tick-borne disease, etc.) Why are deforestation and extinctions problematic for the human population? What factors are affecting animal populations? - Answer -Deforestation, animals loose their habitat -Animal overexploitation See video about the reintroduction of wolves in yellow stone park and be able to explain why factors that affect one species in an ecosystem may indirectly affect other species in that ecosystem - Answer Wolves are a keystone species, once they left, elks affected other animals such as sea otters, bees, and even birds. Describe the trends in loss of insects species and the leading factors causing the decline of insect populations - Answer -Habitat change, e.g., monocultures in agriculture, draining wetlands, soil loss - Pollution, e.g., pesticides, fertilizers - Biological factors, e.g., invasive species - Climate change - Insects play important roles in the functioning & stability of ecosystems -Estimated current proportion of insect species in decline is 41% What are examples of ways you can be exposed to chemicals in the environment - Answer -Inhalation -Ingestion -Dermal contact What are the routes of exposures to environmental chemicals; which is most likely to result in the transfer of chemicals to the blood? - Answer -Absorption: movement into systemic circulation -Distribution: movement to body tissues/organs -Metabolism: how enzymes/ processes in body change the original molecule -Excretion: elimination from body Why is the dose of an exposures an important factor - Answer -Depending on how much of the toxin you ingested, it can affect the body negatively Why are animal studies important and why do we need epidemiological studies as well? - Answer -Help us see some effects of toxins but epidemiological studies study the effects of toxins on human which is more important What is aflatoxin B1 and how might an American college student be exposed to it? - Answer -Can be found in food such as peanut butter -Is a carcinogen Environmental risk assessment and what components of the risk equation - Answer -A tool to quantify the likelihood and magnitude of a risk that might result from human activities -Concentration x exposure x toxicity = risk Dietary supplements: are natural products always safe, are they regulated? - Answer - Natural product are not always safe -Can cause severe liver injury -Are not regulated and are not made to treat, diagnose, or prevent diseases Why was it hard to find a correlation between cigarettes and cancer? - Answer The reason its hard to see the causes is that there is many things in cigarettes and the effects are seen years later so its hard to find the causation. Explain the concept of environmental health and the importance of environmental exposures to global health - Answer -Environmental health addresses all the physical, chemical, and biological factors external to a person and all the related factors impacting behavior -Air pollution Explain the top 10 causes of death from the environment and their causes. Know the risks from air pollution and what pollutants are key contributors to indoor and outdoor air pollution - Answer -10 causes of death Stroke, Ischaemic heart disease, Unintentional injuries, Cancer, Chronic respiratory diseases, Diarrhoeal diseases, Respiratory infections, Neonatal conditions, malaria, intentional injuries -Air pollution is a major risk to health an impacts diseases from stroke, heart disease, lung cancer, and chronic acute respiratory diseases - cooking and smoking Clean air act; know detail about each of the 6 criteria air pollutants - Answer The clean air act requires EPA to set standards for six common air pollutants Particulate matter Ground-level ozone Carbon monoxide Lead Sulfur dioxide Nitrogen dioxide Be able to explain the types of environmental exposures discussed on slide 3o, how these exposures can be framed in terms of the epidemiological triad - Answer -Host: poor people -Agent: air pollution -Environment: air pollution Who is disproportionately affected by environmental exposures and why? What action can help improve environmental health - Answer -Children under five and adults between 50 and 75 are most affected by the environment; mostly affect the poor -Pass smoking bans - Always use health in all policies -Change consumption patters -Increase access to safe water -Reduce occupational exposures -Apply low carbon strategies