EHST 2110 exam 1

population dynamics, people food predicament, food quality

population

individuals of the same species living together within a given area

community

different organisms are not scattered, but live together in a mannerly order; changes of #s of one species can have major consequences

ecosystem

functional units of nature in which living organisms interact with each other and nonliving components of their environment to process energy and cycle nutrients

population dynamics

study of ecological principles that govern the ways in which populations change in size

biotic potential

maximum achievable growth rate with unlimited space in the absence of limiting factors

environments resistance

measured different between biotic potential of a population and the actual observed rate of growth

population growth

visualized graphically as S curves (sigmoidal) and J curves (exponential and often lead to crashes)

doubling time

phenomenon that describes that amount of time it takes for a population to double in size

death rate factors

development of culture, agriculture revolution, and industrial, medical, and scientific revolution

total fertility rate

average number of children per mother during reproductive lifetime

growth rate

rate of natural increase (birth rate - death rate/10)

demographic transition

phenomenon of falling both birth and death rate

typically following industrialization

less labor is needed

megacity

city with 10 million+ people living in it

food chains

transfer of food energy from a given source through a series of organisms

producers

foundational, green plants that convert sunlight energy into food energy (autotrophs)

consumers

animals including herbivores and secondary carnivores

decomposers

primarily fungi and bacteria (some insects)

recycle detritus back to soil to be available for use by primary producers

laws of thermodynamics

1. energy cannot be created or destroyed but may change from one form to another

2. with every successive transformation of anergy, there is a loss of usable energy

   1. all energy is moving toward an ever less available and more dispersed space

entropy

all energy is moving towards an ever less available and dispersed space

biomass

dry weight per unit area (greatest at the producer level)

decreases with increased trophic levels

basal metabolic rate

minimum amount of energy to power human body maintenances, not including energy for activity

undernourished

<1.2BMR food intake/day

malnutrition

inadequate food intake

kwashiorkor

protein deficiency affecting millions of kids in tropical areas like Africa

develops in babies who only eat/drink starchy, low protein foods

discoloration of hair, white skin patches, retardation of growth, protruding abdomen, and loss of appetite

marasmus

overall calorie/protein deprivation

starvation in kids <1 years old who are no longer breastfed causing diarrhea, thin wasted, loose wrinkles, and large eyes

vitamin A deficiency

major cause of childhood blindness

no eggs/dairy products and leafy greens

can’t fight infectious diseases and changes the mucous membrane lining of the respiratory, GI and UT tracts

scurvy

lack of vitamin C causing appetite loss, diarrhea, tenderness and discomfort in the legs, hemorrhaging, feeling paralyzed, ulceration of gums and loss of teeth, and death

was common in pirates

anemia

lack of iron

most common nutrient deficiency (most commonly found with vegetarians)

adulteration

deliberate addition of inferior/cheaper materials into a supposedly pure food product to stretch out supplies and increase profit

1906 Pure Food and Drug Act

protect consumers against adulteration, mislabeling of foods, and harmful ingredients in food

trade-off

to ensure of no insect/rodent parts in food must use more pesticide which can be more detrimental

food defect action levels

maximum limit of contamination or above which the agency will take legal action to remove the product from the market

recombinant bovine growth hormone/bovine somatotropin

injected into dairy cattle every two weeks to increase the milk production by 10-20%

tolerance levels

maximum amount of pesticide residue allowable on raw agricultural commodities

set by EPA based on results from field trials preformed by pesticide manufacturers when applied properly

1996 food quality protection act

required EPA to consider consumption habits and unique vulnerability of children when setting tolerance levels

national academy of sciences

negligible threat to public health from pesticide residue on food for the general population

organic

chemical free production, no antibiotics for animals, no genetically modified foods, or irradiation of foods, and can’t be grown in soil amended with sewage sludge

food additives

substances that are intentionally added to modify taste, texture, nutritive value, appearance, and resistance to deterioration

natual additives

salt, sugar, and other spices

synthetic additives

factory made chemicals that are identical to natural ones, often used to fortify foods in vitamins

1958 food additives amendment

1. amount of additive that is likely to be consumed along with the food

   1. cumulative affects of ingesting small amounts of additive over a long period of time

delaney clause

prohibits use in food of any ingredient shown to cause cancer in animals/humans

death angel (amanita)

commonly grows in fairy wings in woods and lawns in Western America

1-2 bites can kill an adult

water hemlock

commonly misidentified as edible and eaten; sweet but highly toxic; cicutoxin is neurotoxin that is deadly

castor bean

shrub like plant grown ornamental and its oil is toxic; leaves are highly toxic and seeds contain ricin; 1-3 seeds can kill a child, 4-8 seeds can kill an adult

jimsonweed

common weed contains toxic alkaloids in all parts of the plant (leaves and seeds are most dangerous)

alfatoxin

mycotoxin produced by asperilligus flavus mold that grows on nuts, grains, and peanuts; can cause serious liver damage and is carcigenic

ergot

fungus affecting cereal grains; produces a toxic alkaloid, ergotamine, that causes ergotism (st. anthony’s fire) after ingesting

ciguateria poisoning

caused by eating large reef-dwelling fish containing potent algal toxin; common in HI and FL

scombroid poisoning

ingestion of a toxin produced by bacteria on flesh of fish that haven’t been refrigerated/handled properly after catching; cannot be broken down by cooking, canning, freexing, or smoking

paralytic shellfish poisoning

eating shellfish contaminated by saxitoxin which is a nerve poison produced by dinoflagelletes

infection

caused by a large number of live organisms

intoxication

ingesting preformed bacterial toxins

salmonellosis

associated with eating poultry, meat, or eggs, with large numbers of rod shaped bacteria; symptoms develop 12-24 hours; may be a carrier for months; could develop chronic arthritis

campylobacter jenuni

most common food borne illness (1.3million cases/year); undercooked chicken and turkey are major causes because the bacteria is always on poultry carcasses; experience symptoms within a week

E. coli (0157:H7) poisoning

multiplies in the digestive tract and produces a toxin that damages the cells of intestines; very low ineffective dose (<50) that is secreted from cattle (utters and fecal matter) and gets on to food that isn’t handled properly

listeriosis

caused by listeria monocytogenes and is associated with mammals, birds, fish, ticks, crustacean hosts, and food processing environments; symptoms develop in 30-90 days; found in cold cuts and dairy which can be very dangerous for pregnant women

vibrio fulnificus

free-living marine bacterium living in warm waters and contaminates oysters and other shellfish

clostridium

most common bacterial pathogen associated with poultry related illnesses because it develops when meat is unrefrigerated for hours

staphylococcus aureus

common bacterium found in pimples, boils, hangnails, and sneeze air droplets; humans are main source; often misidentified as the 24 hour flu

botulism

most serious and deadly food borne illness caused by clostridium botulinum that produces a deadly neurotoxin due to home canning (must boil for 15-20 mins); never feed babies honey

norovirus

most common viral infection (~20 million gastroestinitis); fecal contamination of food and water; serious issue on cruise ships

Hepatitis A

associated with consumption of raw/undercooked clams/oysters harvested from sewage polluted waters; GI problems and jaundice; virus is shed in urine and feces

parasitic protozoans

amoebic dysentery and giardiases associated with ingestion of sewage contaminated drinking water/transmission of food handlers not washing hands

helminths

worm foodborne ailments from consuming raw/undercooked fish

trichinosis

foodborne illness caused by parasitic round worm primarily found in undercooked pork

danger zone

temperatures between 41 degrees and 140 degrees Fahrenheit.