Science Exam #3

What is the difference between the caloric and nutritional value of food?

Amount of calories does not equal the amount of nutrition it can provide - a cow provides fewer calories than the amount of calories in wheat it consumes, but provides much more nutrition than wheat can provide.

List features of traditional and industrial agriculture.

Traditional: Lower production, often polycultures, topsoil is often covered, fewer chemicals, sometimes organic

Industrialized: Higher production, usually monocultures, topsoil is uncovered for part of the year, more chemicals, rarely organic

What are some issues with topsoil erosion and irrigation systems?

• Makes everything very dusty, soil gets dried out

• Leaving field bare makes loss of nutrients easier

• Loss of fertility

• Soil salination caused by traces of salt in irrigation waters

• Water logging can occur when irrigation area has poor drainage

What is agrobiodiversity?

The diversity of food plants in the human diet, lost due to cheap, easy to grow and easy to ship monoculture crop hybrids

What are the benefits and downsides of chemical pesticides?

• Benefits: Protects crops and defends from predators

• Downsides: Can be toxic to skin, eyes and even entire body; can seep into soil, plants, water and air

What is the “pesticide treadmill”?

When pests or weeds develop genetic resistance to chemical pesticides, requiring farmers to use higher concentrations or more toxic, newer chemicals to manage them

What are the benefits of genetically modified crops?

They can harm insects to protect plants, but not harm humans

What is integrated pest management?

Combining a variety of techniques, can manage pests for lower costs and reduced risks to people and the environment

What are some types of aquifers?

Confined: Surrounded by earth on all sides

Unconfined: Aquifer touches air

What is “virtual water” and “water conflict”?

Virtual Water: Water required to produce goods and services

Water Conflict: Access to water is spread out among urban growth interests, irrigation interests, recreation interests and wildlife interests

What is subsidence?

When the ground collapses when water is removed, sinkholes can also be caused in extreme cases

What are the primary functions of the Clean Water Act?

• Grants for water quality and pollution research

• Grants for construction of treatment works

• Sets standard and penalties for discharge

• Permitting for various forms of discharge

• Citizen suits and whistleblower protection

• Funds for wastewater treatment and pollution control

What is the difference between minerals and rocks?

Minerals: Naturally occurring element or inorganic compound that exists as a crystalline solid

Rocks: Solid combinations of one or more minerals

What are the three basic types of rocks?

Sedimentary: Deposited layers of pre-existing rocks

Igneous: Produced from volcanic activity

Metamorphic: Formed when other rocks are subjected to intense heat and pressure

What are strategic metal resources and rare earth metals?

Strategic: Present in very low quantities and are highly valuable and sought after (Manganese, Cobalt, Lithium)

Rare Earth: Present in extremely low quantities but are vital for many industries

List the types of mining.

• Surface mining

• Open pit mining

• Strip mines

• Mountaintop removal

• Subsurface mines

What is net energy production?

Outputs - inputs

What is “peak production” for oil reserves?

The maximum production rate of an oil reserve - much of the world’s reserves are at or over the peak

What is the difference between light and heavy oil?

Light: requires little processing due to fewer contaminants

Heavy: more processing, but can be used to produce heavier oil products like asphalt

How do electrical generators work?

Converting motion into energy

What are some examples of energy inefficiencies?

Data centers, cars, homes and anything mechanical

What are some examples of renewable energy sources?

Wind turbine, lighter hybrid or electric cars, grass and gardens on roof, solar panels and solar cells

List the types of environmental hazards.

• Biological: infectious diseases, nontransmissible diseases, TB, HIV, Hep. B

• Chemical: Carcinogens, mutagens, teratogens, hormone/endocrine disruptors

• Natural

• Cultural

• Lifestyle

What is the difference between an epidemic and a pandemic?

An epidemic is a sudden spike in disease cases within a specific, localized community or region.

A pandemic is an epidemic that has spread over multiple countries or continents, affecting a large number of people worldwide.

What are the three types of toxic chemicals?

• Carcinogens

• Mutagens

• Teratogens

What factors contribute to chemical toxicity?

• Genetic predisposition

• Solubility

• Acute vs. Chronic

• Persistence

What is the “Four R” approach to recycling?

Variable: Refuse/Recover/Repurpose/Rot, reduce, reuse, recycle

What is the “cradle-to-cradle” design?

Recovering and recycling old products, organic nutrient cycling and environmental stewardship

What are the types of primary and secondary recycling?

Primary: recycling

Secondary: Downcycling and upcycling

What are the basic tenants of the three major pieces of hazardous waste legislation?

• RCRA - set standard for the management of several types of waste, issued permits allowing companies to produce and dispose of certain amounts

• TSCA - requires companies to notify EPA before introducing a new chemical

• CERCLA - “Superfund Act” identifies sites where hazardous waste has damaged the environment and cleans them up, gives citizens right to know what chemicals are being stored and released