test 2 Flashcards
In the real world, many factors determine the number of organisms in any one population. Yet a superfly with unlimited food and no mortality would show what type of growth?
j-shaped growth curve
The demographic transition refers to a country’s change from…
high birth and death rates to low birth and death rates
Tundra biomes occur…
at high latitudes and altitudes, where the growing season is short
A population growing at 2.5% per year should double in about ___ years.
28
Widespread starvation is an example of ____ population control
density-dependent
Which of the following sequences is an example of exponential growth rate?
4,8,16,32
Carrying capacity is the population…
that an environment can support on a long-term basis
In a population whose mortality and natality are balanced, there are…
about the same number of old and young
Crude birth rates are measured in terms of children born…
per 1000 people each year
An “r-adapted” strategy of population growth includes a tendency for…
little parental care and protection, production of many small offspring that mature early, and organisms to have short lives and grow rapidly
Life expectancy is the…
number of years an individual of a certain age will probably live
Location of specific biomes can be predicted based on…
precipitation and temperature
The zero population growth rate in the more highly developed countries is ___ children.
2.1
Endocrine disruptors…
disrupt normal hormone functions
Teratogens cause abnormal growth specifically in…
embryos
If solubility is an important characteristic in toxic material movement in the environment and body, which of the following statements is true?
oil-soluble compounds accumulate in the body
Hazardous substances ___ while toxins are ____.
are dangerous substances; poisonous substances
Biomagnification is a concentration of toxins…
as predators consume and store toxins stored in the bodies of their prey
The difference between “total growth rate: and “natural increase” is that total growth rates…
include immigration and emigration as well as births and deaths
Highly persistent toxic chemicals…
retain their toxicity as they cycle through the food chain and environment
Historically, up until the middle ages, populations were mostly limited by…
disease, famine and war
Deciduous forests…
have trees that shed their leaves seasonally
In evaluating the interaction of two chemicals that have an adverse impact on a specific organism, the most serious detrimental chemical interaction would be described as…
synergistic
A dependency ratio is a comparison between the numbers of…
working and nonworking people
Genetic diversity is lost in a small population when…
only a few individuals survive a catastrophe
A demographic transition is expected to accompany…
economic development and stabilization
The histogram on the left represents a population whose birth rates…
have recently decreased
The population represented by the age class histogram on the right wil…
grow substantially in the future
Boreal forests are generally…
slow-growing because of the cold temperatures
Which of the following is an abiotic population control mechanism?
water shortages
Island biogeography explains the phenomenon of ___ terrestrial species on islands small and far from the mainland when compared to larger islands that are closer to the mainland and have ___ terrestrial species.
fewer; more
The graph above indicates that more children die…
when their mothers are illiterate
Wetlands are biomes that…
are wet at least some of the year
Predation is considered to be a(n) ____ factor.
extrinsic and biotic
Fetal alcohol syndrome is caused by exposure to a(n)…
teratogen
Allergens are substances that…
activate the immune system
Tropical seasonal forests are specially adapted to tolerate…
annual cycles of severe drought and heavy rain
The saying “the dose makes the poison” means that…
nearly anything can be toxic at some level
What environmental factor does not change between “b” and “e” in the diagram?
light penetration, temperature, nutrient availability, and oxygen content
What aquatic ecosystem phenomenon is illustrated in the diagram?
vertical stratification
The biome type that has a short growing season and is summer feeding and breeding grounds for caribou and muck-ox is the…
arctic tundra
The term “fecundity” refers to an organism’s ___ while fertility is ____.
physical ability to reproduce; actual number of offspring produced
Malthus argued that ___ is the ultimate cause of social and environmental problems and Marx argued that population growth ____ social and environmental problems.
excess population growth; results from
Which of the following types of population curves would best represent a group of elephants that enter a new, open habitat and become a stable part of that ecosystem?
s-shaped curve
Mangrove trees are found along ___ shorelines
tropical saltwater
The World Health Organization regards health as primarily a matter of ___ well-being.
physical, mental, and social
Logistic growth rates are those in which a population…
grows rapidly when conditions are good, then slows as it approaches carrying capacity
Historically, the greatest threats to human health came from…
pathogenic organisms
Density-independent population control factors cause mortality…
regardless of population size
Health organizations now use the ____, a tool to _____.
DALY; judge the total impact of the disease rather than only measuring how many people die
