module 2 enviro

what is biotic potential?

the maximum number of offspring that could be produced if there were no constraints

what is carrying capacity?

the maximum population that can be maintained with the resources that are available

what are some factors that can affect the carrying capacity?

predation, disease, competition, limited resources, and random events

What are some key population parameters in population models?

N = numbers

r = rate

t = time

what are the main 4 factors that influence r?

births, immigration, deaths and emigration

Which factors increase r?

births and immigration

what factors decrease r?

deaths and emigration

How do exponential and logistic growth differ?

exponential growth assumes unlimited resources and continuous growth, while logistic growth accounts for resource and environment limits

what is the difference between density dependent and density independent factors of population growth?

density dependence slows as population increases while independence impacts growth regardless of density

what is MSY?

MSY represents the maximum harvest from a population that leaves enough to maintain stable reproducing

what does it stand for and what does that actually mean?

maximum sustainable yield

How do r and K selected species differ?

r selected species have rapid reproduction with little to no parental care while the K species have slower reproduction within the bounds of the carrying capacity

what is the difference between an intrinsic and extrinsic factor?

intrinsic operate within an organism or between individuals of the same organism, while extrinsic operate from outside of the

how does the island size relation to potential for population extinction?

larger islands generally experience fewer extinctions because that can support larger populations

what is genetic drift?

the random shifting of predominant genetics during to random events

what is the founder effect?

when a small groups starts a new population

what is the bottleneck effect?

results from disturbance events, funneling genetics into a reduced gene pool that contains less fit genetic characteristics

what are the two main viewpoints on the relationship of poverty and human population size?

overpopulation which leads to poverty due to excessive resource use and poverty leads to overpopulation due to instability

what do the terms in the equation I = PAT stand for/represent?

I = environment impacts

P = the product of the population size

A = times affluence

T = technology used to produce goods and services

are fertility rates generally increasing or decreasing globally for humans?

decreasing

where are they generally still the highest (generically not specific locations)

developing countries

what are the 4 stages of the model that generally relates birth/death rates to technology/development

stage 1 : pre modern society → high death rates + high birth rates

stage 2 : industrializing → decline in death rates + raised birth rates

stage 3 : mature industrial economy → birth rates falling/stabilizing

stage 4 : post industrial → low birth and death rates

what are some factors that encourage a high fertility rate, what are some that promote low fertility rates

high rate

• desire for children

• care for parents

• lack of contraceptive

• religious/cultural views

• desire to produce son

• male pride in fathering

low rate

• female education/independence

• family planning

what are some of the main factors driving human migration in modern times?

what are some of the main reasons that diseases and childhood mortality have been reduced?

improved and increased access to clean water, food, sanitation and health care has reduced risks

what are some of the contributing factors to continued disease spread?

diet, nutrition, pathogens, toxins, stress, genetics, trauma

what are “super bugs”?

bacteria/viruses that have developed resistance to the medications used to treat them

what is the 10/90 gap?

90% of the disease burden occurs in developing countries, 10% of all health care dollars are spent in developing countries

what are some of the main reasons that chronic conditions have increased?

increase life span (conditions couldn’t become chronic bc life span was short), poor diet, environmental exposures

what is the difference between a toxin and a toxicant?

toxins are produced naturally, toxicants are produced by human activity

can all substances be toxic at the correct dose?

yes

what is the difference between acute and chronic exposure?

acute is short term/ single event, chronic is repetitive/long term exposure

what is acute exposure?

short term often single event exposure

what is chronic exposure?

repeated, long term exposure

what is the difference between acute and chronic responses?

acute is sudden often severe damage, chronic is long-lasting, possibly permanent damage

allergens

antigens or combine to make antigens that are foreign objects and trigger an immune response

immune system depressants

suppress immune response, increasing susceptibility to disease

endocrine disrupters

disrupt hormone functions, which signal molecules that regulate many key functions; can harm health and reproduction

neurotoxins

metabolic poisons that attack nerve cells

what are some things that influence exposure to toxic substances?

mutagens, teratogens, carcinogens

what is the difference between a hydrophobic and hydrophilic substance?

hydrophobic are water fearing while hydrophilic are water loving

are hydrophilic substances soluble in water or lipids?

hydrophilic substances are dissolvable in water not lipids

are hydrophobic substances soluble in water or lipids?

hydrophobic substances dissolve in lipids not water

what are bioaccumulate?

the storing of substances in living tissue, both essential and toxic

what is biomagnification?

the increasing concentration of bioaccumulated substances at each increase in trophic level

what is LD50?

stands for lethal dose 50%, a standard measurement sure to describe the acute toxicity of a substance

what are some of the issues with assessing toxicity with lab animals?

moral/ethical issues and may not have the same response in humans

what are some major contributors to to chronic hunger/famine?

war/conflict, oppression/corrupt government, climate change,

how are famine and malnourishment different?

famine lacks food all together while malnourishment is the lack of nutritious food

what are the major macronutrients?

carbohydrates, lipids and proteins

what are carbohydrates used for?

a source of energy

what are proteins used for?

building muscle mass, provides amino acids that our bodies cannot make

what are proteins used for?

building muscle mass, provides amino acids that our bodies cannot make

what are the major micronutrients?

vitamins and minerals

what are some issues with monocultures of livestock/crops and factory farming?

monocultures are susceptible to novel pathogens, excessive antibiotic used can lead to a great increase to antibiotic resistant bacteria

what is a GMO or GM plant?

genetically modified plants

what has been the main focus in creating GM plants?

centered around pest resistance or herbicide resistance

are ecological or health risks of GM plants greater now?

health impacts are low, making the food generally safe