Natural Science Exam 2 Part 1

How have global trends in food production changed with industrial agriculture?

An increasing amount of the world’s food comes from large scale operations. Food production has increased dramatically therefore lowering food costs.

What source of food is consumed the most in wealthy countries and why does it

signal wealth?

What is food security?

The ability of individuals to obtain sufficient food on a day-to-day basis.

What is famine?

large-scale food shortages leading to starvation and death, often results from conflict disrupting farming and food distribution.

Why is a variety of food important to a healthy diet?

Because human health relies on essential nutrients such as carbohydrates, proteins, fats, vitamins, minerals, and water that you receive from a variety of foods.

What is malnourishment?

occurs when diets lack specific nutrients or are imbalanced with excess sugars and starches.

Why is hunger still an issue globally despite an excess of food produced?

Global food waste remains an issue. About 30% of food production is spoiled in storage, transits, used inefficiently, or thrown away.

What are primary sources of food globally?

Corn, soybeans, wheat, and rice

What are certified animal feeding operations (CAFOs) and why are they

controversial?

CAFOs are confined animal feeding operations and they are controversial because they are regarded as cruel to the animals and there are environmental issues such as waste production.

What practices of seafood production are problematic for the environment?

Over harvesting and habitat destruction through trawling and longline fishing threaten fisheries.

Why is it important to eat lower on the food chain?

Because a return to plant-based diets could improve health and reduce environmental impacts.

How is soil an interaction?

Soil can be considered a living ecosystem by itself because it contains minerals, partially decomposed organic molecules and a host of living organisms.

What are the primary components of soil?

the six components of soil include sand and gravel, silts and clays, dead organic material, soil fauna and flora, water, and air.

Why do we need to protect soil?

Because healthy soil can determine soil fertility and support biodiversity.

What are the different soil horizons?

O horizon: organic layer with leaf litter and soil fauna

A horizon: a mix of organic material and minerals, supporting plant life

E horizon: light-colored, washed out layer between A and B

B horizon: accumulates clays and minerals leached from the A horizon

C horizon: decomposed rock fragments

What are the four different types of erosion?

sheet-removes a thin layer of soil

rill-occurs when small rivulets of running water cut small channels in the soil

gully-occurs when oils expand to form bigger channels or ravines

steam bank-occurs when soil washes away from steam banks

What is the pesticide treadmill?

when heavy pesticide use drives the evolution of resistant weeds and pests that requires increasingly toxic solutions.

What is a genetically modified organism (GMO)?

organisms with entirely new genes, and even new organisms often called transgenic organism.

What was the Green Revolution?

introduces high yield wheat and rice varieties, significantly increasing food production in developing countries and helping meet the demands of a growing population.

What is environmental health?

Focuses on factors that cause disease, including elements of the natural, social, cultural, and technological worlds in which we live

What are major sources of environmental health risks?

Trauma, infectious agents, pollution, toxins, radiation

What is the difference between health and disease?

health-is a state of complete physical, mental, and social wellbeing, not merely the absence of disease or infirmity

disease-is an abnormal change in the body’s condition that impairs important physical or psychological functions

How has the global disease burden changed over time?

Epidemics like smallpox, polio, and typhoid are able to be controlled. Children’s survival rates have improved and life expectancy has increased.

What is the importance of improved healthcare and sanitation in promoting

environmental health?

Clean water is important to people’s health so this promotes better waste management and prevents pollution. (look more into it)

What are pathogens?

such as viruses, bacteria, protozoans, and parasitic worms cause many human diseases

What are emergent diseases?

newly identified illnesses or those reappearing after at least 20 years

What is conservation medicine?

attempts to understand how environmental changes threaten human health as well as that of natural communities on which we depend

Why are environmental scientists concerned about antibiotic resistance?

Because it makes disease strains more difficult to treat leading to severe health problems. (LMII)

What’s the difference between an allergen and an antigen?

allergens- substances that activate the immune system and cause an allergic reaction

antigens-substances (pollens, bacteria) recognized as foreign by white blood cells and stimulates the production of specific antibodies

What is sick building syndrome?

a condition characterized by headaches, allergies, and chronic fatigue caused by poorly vented indoor air contaminated by various contaminants

What is a neurotoxin?

specifically target nerve cells, causing rapid and devastating damage to the nervous system

What are mutagens vs. teratogens vs. carcinogens?

mutagens-agents, such as chemicals and radiation, that damage or alter genetic material (DNA) in cells

teratogens-chemicals or other factors that specifically cause abnormalities during embryonic growth and development

carcinogens-substances that cause cancer

What are endocrine hormone disruptors?

chemicals that interrupt the normal endocrine hormone functions

What are the pathways that toxins can enter the human body?

Airborne exposure, ingestion, skin contact, workplace exposure

What is the difference between biomagnification and bioaccumulation?

bioaccumulation-process by which organisms may selectively absorb and store toxins in their bodies

biomagnification-the increase in concentration of certain toxins in successively higher tropic levels of a food chain or web

What are persistent organic pollutants (POPs)?

long-lasting chemicals found worldwide in the environment and living organisms

What is the LD50 of a toxic chemical?

the dose of which 50 percent of the test population is sensitive. in other words, the lethal dose.

Why were people moving to LA in droves during the 1940s?

Because LA had a lot of appeal as a bustling city, good weather, Hollywood, and it had a reputation as being a healthy place to live.

What is the definition of smog?

a fog made heavier by the presence of smoke or other chemical fumes

What was the Air Pollution Control District and what was their job?

The Air Pollution Control District was responsible for regulating sources of sir pollution in a given county such as power plants, highway construction or housing developments

What is a Ringelmann Chart and why was it used?

It was a chart with different shades of grey used to determine how polluted a source of air pollution was. The understanding was that the darker the grey, the more polluted.

What conditions about the environment within and around LA made it susceptible to the accumulation of smog?

LA is ringed on three sides by mountains which essentially makes a bowl shape, trapping smog within. additionally, there’s a lot of hot air from the deserts which causes a temperature inversion and prevents the toxin air from escaping.

Who was Dr. Haagen-Smit and what was his role in our understanding of smog?

Dr Haagen-Smit was a plant chemists who specialized in isolating plant proteins. He was asked to take a sample of the air and deconstruct it to find out what the components were. He discovered that it was large concentration of ozone.

Who was S. Smith Griswold and what was his role in managing air pollution in California?

S Smith Griswold was chosen to be the new commissioner of APCD. He increased the staff and enforcement efforts to fix the issue. He also insisted that individual garbage incinerators be shut down.

Why was garbage incineration banned and how did people react to the ban?

They were banned because they generated ash and smoke which heightened the smog problem. People were not happy with the ban because people were against the government forcing even minor changes on their lives.

Who created the Stamp Out Smog (SOS) group and how did they inform people, including policymakers about the issue of smog?

The SOS group was created by a set of ladies in Beverly Hills. They held protests to put pressure on politicians. They did letter writing campaigns and joined forces with hundreds of organizations. they testified about the smog at state and federal level.

What was ultimately the role of cars in smog production?

The chemicals being released from the cars, specifically the hydrocarbons were primarily to blame for the smog problem.

What compound had to be removed from gasoline in order for catalytic converters to work?

Lead had to be removed.

What was the purpose of the first Earth Day in 1970?

The first earth day was the single largest protest in American History. it’s purpose was to advocate for environmental protections and demand that congress take action.

How did the smog events in LA impact the development of the Clean Air Act (CAA)?

It brought attention to a serious problem so that politicians could no longer ignore it. This led to the creation of the Environmental protection agency and then the Clean Air Act in 1970.