Exam 2
What is food security?
Ability to obtain sufficient, healthy food on a daily basis.
Teratogens
Agents such as chemicals or other factors that specifically cause abnormalities during embryonic growth eg. Alcohol
What are ways toxins move through the environment?
Air, water, soil
The Endangered Species Act provides?
All of the above: A. Assistance to private landowners to find compromise to protect species and meet landowners economic needs, B. Directions for making a species' recovery plan, C. Enforcement, D. Criteria to indentify species at risk
Why are fires damaging more land each year?
All of the above: A. Fire suppression was the U.S. forest management policy for many years, leaving a lot of dead debris in forests, B. Climate change is making dry climates even drier, C. More winter precipitation is falling as rain rather than snow making soils dry out sooner
Water erosion of farmland has increased because farmers
All of the above: A. Leave soil exposed between rows of crops, B. Irrigate excessively, C. Overgraze lands causing soils to be exposed
The main concern over concentrated animal feeding operations is
All of the above: A. That overcrowding of the animals leads to diseases, B. That a lot of antibiotics are fed to the animals to keep them healthy, C. That they generate significant air and water pollution
Diseases such as the recent outbreak of Cholera and Ebola are
All of these are characteristics of diseases such as Cholera and Ebola A. Caused by pathogenic organisms, B. Called communicable diseases, C. Called emergent diseases, D. Happening more often in the past 20 years
Tundra
An extremely cold, dry biome, treeless, found at high altitudes
What is the difference between bioaccumulation and biomagnification?
Bioaccumulation happens in the individual while biomagnification happens in the food chain
What is bioaccumulation?
Bioaccumulation happens when organisms absorb and store toxins or chemicals in their bodies
Define biodiversity and give three types of biodiversity essential in preserving ecological systems and functions
Biodiversity is the number and variety of a species. Three types of biodiversity essential in preserving ecological systems and functions are: Species diversity: number of different species genetic diversity: variety of genes within a species Ecological diversity: complexity of a community
How do humans benefit from biodiversity?
Biodiversity provides food and medicine. Genetic material from wild plants is used to improve domestic crops and pharma products are derived from wild animals, plants and microbes.
What is biomagnification? Give an example
Biomagnification occurs when toxins from lower tropic levels are accumulated in an individual and concentrated at higher trophic levels. An example of biomagnification was DDT which almost led to the extinction of bald eagles in the 1960's. DDT was accumulated in individuals in lower trophic levels and concentrated in bald eagles.
To reduce the climate impact of what you eat, should you eat less, tuna, chicken, cheese or eggs?
Cheese
What are ways soil loss can be reduced?
Contour plowing (plowing across hill vs. up), strip farming (planting different crops in alternating strips), and terracing (creating shelves of earth to hold soil)
What crop do farmers in the U.S. grow the most?
Corn
What is environmental health?
Environmental health focuses on environmental factors that cause disease (natural, social, cultural and technological factors)
Why are invasive species a threat to biodiversity?
Invasive species compete with native species and overpopulate because they are free of predators, diseases and resource limitations.
What is true about the relationship between the percent converted land and the percent protected land?
Inversely related, the biomes with they highest percent of converted land are the areas where the majority of humans live
Explain the concept of land ethic
Land ethic is having an understanding of our relationship to the land and conserving land for more than just its economic value Examples of land ethic include: knowing how your home is heated, knowing where your food comes from
Wind erosion is most likely to cause problems in
Open, arid regions
What threatens grasslands and how can they be protected?
Overgrazing threatens grasslands, methods of protection: Rotational grazing Raising wild species (s/a bison= more efficient foragers)
High population density is one of the problems with disease control in human population. Name other problems
People are mobile: the accessibility of travel by plane, train, etc. makes it harder to control diseases Climate change and degradation of ecosystems: allows pathogens to expand into new territories Pesticide resistance: Eg. Mosquitos developing resistance to pesticides allowing them to expand into other areas bringing with them malaria Antibiotic resistance
The World Health Organization regards health as primarily a matter of
Physical, mental and social well-being
What are the agricultural inputs?
Plants, soil, water, solar energy, nutrients, energy and pesticides
What are the pros and cons of genetic engineering?
Pros: has potential to increase quantity and quality of our food supply, improve yields, create crops that are resistant to certain factors, faster growth rate Cons: increase herbicide use, pesticide resistance, increase of hormones in our diets
What does sustainable farming aim to do?
Reduce or repair damages caused by destructive harming practices
What are examples of chemical deterioration of soils?
Salinization and acidification
What are ways consumers can contribute to sustainable Ag?
Shopping locally, shopping seasonally, eating low on the food chain
How do the size and design of nature preserves influence their effectiveness? What is a proposed solution to this problem?
Size and design of nature preserves influence their effectiveness because different species have different necessities (core vs. edge habitat, fragmentation) a proposed solution to this problem is the creation of corridors of natural habitat that allow movement between reserves
What are methods of sustainable farming?
Soil conservation, crop rotation and nutrient management
Why is soil fauna important?
Soil fauna are important because they are responsible for providing the nutrients plants need to grow and they can help filter and purify water
What GMO crops are grown in the U.S?
Soybeans, sugar beets, canola, cotton, potato, cotton, corn, summer squash, apple, papaya and alfalfa
Which biome has the U.S converted into farmland?
Temperate Grassland
Which biome has a hot and warm season?
Temperate forests
What two things influence terrestrial biomes?
Temperature and precipitation
What is false about trade in endangered species?
That overharvesting affects animals more than plants
What is soil?
A mixture of 6 components: sand and gravel, silts and clays, dead organic material, soil fauna and flora, water, air
What are two ways microbes acquire antibiotic resistance?
1. A mutation happens and an antibiotic resistant bacterium develops resulting in an antibiotic resistant colony 2. A harmless drug resistant bacterium conjugated with a harmful bacterium resulting in a harmful drug resistant bacterium which then leads to a resistant colony
What is a biosphere reserve and how does it differ from a wilderness area of wildlife preserve?
A biosphere reserve is a protected area that is divided into zones with different purposes. Central core region: critical ecosystem functions and endangered wildlife Buffer zone: ecotourism and research facilities Peripheral region: sustainable harvesting, permanent habitation
Boreal Forests
A forest made up primarily of coniferous evergreen trees that can tolerate cold winters and short growing seasons
What is the main reason ecological diseases are important to understand?
Because they could be transferred to humans or jump species to humans
Why is meat a good indicator of wealth?
Because it is expensive to produce in terms of the resources needed to grow an animal
What are the two types of temperate forests?
Deciduous and coniferous
Planting perennial crops
Decreases soil erosion
Temperate grasslands
Deep, nutrient-rich soils, enough rain to support abundant grass but not trees, plants adapted to drought, fire, heat and cold
What is the most efficient way to irrigate crops?
Drip irrigation
Tropical Savannas and Grasslands
Dry most of the year, grasslands with sparse tree coverage, rainy season, plants=drought heat and fire adapted
Define emergent diseases and give a recent example
Emergent diseases are communicable (contagious) pathogenic diseases that have been previously unknown or have been absent for at least 20 years. A recent example of an emergent disease could be the Ebola outbreak in 2014 or the current COVID-19 pandemic.
What are some problems with indiscriminate pesticide use?
Endangers non-target species, creates widespread pesticide resistance, leaves residues and has human health impacts
Estrogen-like compounds that can disrupt normal cellular function are called
Endocrine disruptors
Water logging results from
Excessive irrigation
Two problems encountered in human health risk assessment are
Extrapolation of data to low doses; extrapolation of data from non-human species to humans
Growing more genetically modified crops has decreased pesticide use in the U.S
False
Pathogens are no longer a problem in the United States
False
What are the benefits of biodiversity in general?
Food, medicine, ecosystem stability (helps communities withstand disturbance), aesthetic and existence values (fishing, hunting, camping, hiking) maintaining biodiversity makes economic sense
One way to reduce fertilizer use is to
Grow a cover crop and then plow it into the soil
The benefits of organic farming do NOT include
Grows the same one crop every year
Wildlife bridges aim to reduce the impact of which factor in biodiversity loss?
Habitat Loss
The main reason for the current high rate of animal extinction is?
Habitat destruction worldwide
What are the human impacts on biodiversity? HIPPO
Habitat destruction, invasive species, population of humans, pollution and over-harvesting
Examples of overharvesting do NOT include
Having a permit and killing only the amount listed on the permit.
Temperate Scrublands
Heavily populated by people, biologically rich, cool, moist winters and hot, dry summers
Deserts
Hot or cold but always dry, vulnerable to disturbance because they have slow recovery times, plants and animals adapted to environment
What has been the human impact on extinction?
Humans have been causing extinction thousands of years ago, but our impact has recently increased
Which of the following statements is true about a toxic substance?
If a substance is toxic, its toxicity is highly dependent on its form and where it is present in the environment
Heavy use of pesticides
Increases soil erosion
Leaving fields bare during the winter
Increases soil erosion
flood irrigation
Increases soil erosion
What are ways to protect forests?
Instead of clear cutting alternatives to protect forests are: Shelterwood harvesting-mature trees are removed in 2 or more cuts Strip-cutting: narrow corridors harvested Selective cutting- small % of mature trees harvested every 10-20 years
Endocrine hormone disruptors
Interrupt normal hormone functions eg. DDT
Which cause of biodiversity loss best explains the following example: zebra mussels being introduced into the Great Lakes
Invasive Species
The pesticide treadmill can be best explained as
The need to use more complex and potentially toxic mixtures of pesticides to combat pests that are developing pesticide resistance
Explain how soybeans grown in Illinois are improving diets in China
There has been an increase in meat consumption in China due to the affordable soybeans grown in the Midwest that is imported to feed livestock
Mutagens
agents, such as chemicals and radiation, that damage or alter genetic material (DNA) in cells
Old-growth forests are notable for containing species that:
are highly adapted to their special environment.
Chemicals can be divided into two major groups, what are these groups? Describe them and their differences.
These two groups are water-solubles and oil- or fat-solubles: Water-solubles are compounds that move rapidly and widely through the environment because water is ubiquitous. Oil- or fat-solubles need a carrier to move through the environment and into or within the body. Once inside the body they are likely to accumulate.
Which biome best matches the following description: contains the most remaining old-growth forests?
Tropical Rainforest and Boreal Forest
Which biome is characterized by abundant rainfall, warm to hot year-round temps and high biological diversity?
Tropical Rainforests
What are the nine major biomes?
Tropical Rainforests Tropical Seasonal Forests Tropical Savannas and Grasslands Temperate Grasslands Temperate Scrublands Temperate Forests Tundra Deserts Boreal Forests
A factor responsible for the fast spread of emergent diseases is high population density
True
Genetically modified organisms (GMOs) are made by taking bits of DNA from different sources to create desired characteristics in an organism
True
Some global diseases have been eradicated and others are nearing eradication
True
The three crops that humans rely on most for the majority of nutrients and calories are?
Wheat, rice and maize
tropical seasonal forest
a biome marked by warm temperatures and distinct wet and dry seasons, often cleared for agriculture and human habitation
What was the Green Revolution?
a large increase in crop production in developing countries achieved by the use of fertilizers, pesticides, and high-yield crop varieties.
Humid tropical forests have extraordinary biological diversity
despite the poor, weathered soils.
Monetary inputs to local economies due to the presence of parks and reserves is
ecotourism
World deserts are
increasing because of logging and grazing
Sustainable farming
is cheaper and safer than conventional farming.
An LD50 is a dose of a toxic chemical that
kills half of the population
As a society, we usually focus money and attention on health risks that are
most well publicized and frightening
Historically, the greatest threats to human health came from
pathogenic organisms
Most people do their own personal risk assessments based upon
personal biases and preferences as well as logic
Highly persistent toxic chemicals
retain their toxicity as they cycle through the food chain and environment
Carcinogens
substances that cause cancer eg. Cigarette smoke
the rise in antibiotic resistance diseases can be linked to
the natural evolution of bacteria when exposed to insufficient doses of antibiotics to kill all the bacteria
Neurotoxins
toxic substances, such as lead or mercury, that specifically poison nerve cells