Ecology Flashcards
What is meant by the term ‘zoonotic disease’? How many of the emergent diseases listed in the article excerpt might be considered zoonoses? (2)
Zoonotic diseases are illnesses that humans can contract from animals. Lassa fever, SARS Coronavirus, Ebola, MERS, Nipah, Rift Valley Fever, Marburg, and Crimean Congo Haemorrhagic Fever are a few examples of these illnesses in the article.
The Ebola virus, the phlebovirus which causes Rift Valley fever and the coronavirus responsible for SARS are all believed to have originated through the handling or consumption of infected animal tissues, typically through bushmeat trade markets. What is another major human viral disease thought to have originated in this manner?
Other major human viral diseases thought to have originated through the handling or consumption of infected animal tissues include chicken pox, smallpox, measles and rabies.
Some major bacterial pathogens have also been zoonotic in origin. Name two major diseases caused by such pathogens. (2)
Bubonic plague and leptospirosis.
Pollution of natural environments can also lead to increased disease prevalence. Suggest two major avenues through which pollution can trigger disease. (2 )
If dangerous compounds are inhaled, they can contaminate the air and cause cancer, cardiovascular problems, and asthma. Water contamination can result in contaminants in the water that, if taken by people, can lead to cancer, diarrhea, and liver damage. Typhoid may also be caused by water contamination.
What is the beneficial impact of access to natural environments on psychological health? (3)
The increased exercise brought on by exposure to natural environments can lead to the release of endorphins, which can enhance mood and mental health. Through photosynthesis, more oxygen is released into the atmosphere in natural settings, people’s breathing is improved, and the beauty of nature can have a beneficial, long-lasting impact on people.
How are dead birds indicators of the West Nile virus?
The presence of dead birds is a sign of the virus because the virus is likely to have caused them to die, and testing the dead birds can reveal whether the virus is present. Birds infected with the West Nile virus tend to become ill and die after infection.
What is a type 1 survivorship curve?
In a type I survivorship curve, mortality is low in the early and middle years and occurs mostly in older individuals. Organisms exhibiting a type I survivorship typically produce few offspring and provide good care to the offspring increasing the likelihood of their survival.
What is a type 2 survivorship curve?
Type II. Many bird species have a Type II survivorship curve. In a Type II curve, organisms die more or less equally at each age interval. Organisms with this type of survivorship curve may also have relatively few offspring and provide significant parental care.
What is a type 3 survivorship curve?
Type III or concave curves have the greatest mortality (lowest age-specific survival) early in life, with relatively low rates of death (high probability of survival) for those surviving this bottleneck. This type of curve is characteristic of species that produce a large number of offspring (see r/K selection theory).
Mathematical Model :
Exponential growth model:
Logistic growth model:
Equations for exponential vs logistic growth models:
