Environmental Biology Test 2
what represents the "living" portion of the ecosystem?
communities
Ecosystems
complex assemblages of many interacting living and non living components
Nitrogen, the most abundant element in Earths atmosphere,
is need to make proteins and nucleic acids
abiotic
nonliving
Consumers
organism that gets energy and nutrients by eating on another organism
Producers
organisms that convert solar energy to chemical energy. aka photosynthesis
Population Density is the number of individuals ____
per unit area
What is the LOCATION and SPACING of individuals within their range?
population distribution
The critical resource whose supply determines the _________ of a given species in a given ecosystem is _______
population size = Limiting Factor
Cellular respiration
process in which all organisms break down sugar to release its energy , using oxygen and giving off CO2 as a waste product
Uniform distribution
rare in nature-- individuals that are spaced evenly , perhaps due to territorial behavior or mechanisms for suppressing growth of nearby individuals ex. seen in some plants
population growth is dependent on the presence of GROWTH FACTORS
resources individuals need to survive and reproduce that allow a population to grow in number
Phosphorus is found only in ___ or ___form on earth
solid liquid
factors that affect distribution:
species characteristics topography habitat makeup
The size and distribution of populations in an ecosystem is influenced by a variety of factors..
such as the availability of resources and the presence of other species, like predators distribution, genetic diversity, initial population size, and density prey availability and habitat structure
Which of these is an example of a population's range of tolerance?
the hottest and coldest temperatures it can survive
Range of Tolerance
the range, within upper and lower limits, of a limiting factor that allows a species to survive and reproduce. highest and lowest temperatures*
minimum viable population
the smallest number of individuals that would still allow a population to be able to persist or grow, ensuring long term survival.
Resistance Factors
things that directly (predators, disease) or indirectly (competitors) reduce population size.
Phosphorus depends on the ________ of rock to release new supplies of phosphate into bodies of water or the soil, where it dissolves in water and can be taken up by organisms.
weathering
Optimum range
where most organisms live because they are comfortable and more successful to breed
All plant and Animal life depend on microbes (bacteria) to convert atmospheric nitrogen into usable forms
which is a part of the Nitrogen Cycle
The word niche refers to an organism's ________, while its habitat refers to its ________.
"address" "job description"
the carbon cycle becomes unbalanced due to ______ that increase the amount of atmospheric _____.
--Human actions ---carbon dioxide
Phosphorus Cycle
A series of natural processes by which the nutrient phosphorus moves from rock to soil or water, to living organisms, and back to soil
Extra carbon dioxide causes problems such as
-global climate change -acidification of oceans -alterations of communities world wide
Nitrogen cycle is dependent on many types of soil bacteria
-its important for plant growth and ecosystem depend on a variety of organism and bacteria to process the cycle
3 types of distributions:
1) Clumped 2) Random 3) Uniform
NUTRIENT CYCLES are biogeochemical cycles that refer specifically to the ________ of life's essential ______ or ______ through an ecosystem.
1) Movement 2) chemicals 3) nutrients
What two fundamental processes(Ecosystem processes) does the ecosystem function through?
1) Nutrient Cycling 2) Energy Flow
Biomes have 3 categories:
1)terrestrial 2)marine 3)freshwater
Species
A group of plants or animals that have a high degree or similarity and can generally only interbreed among themselves.
Population dynamics
changes over time in population size and composition *can predict size of populations
What is a single member of a population?
An Individual
The total area on earth(air,land, or water) where living things are found--
Biosphere
Organization of life:
Biosphere Biome Ecosystem Community Population Individual
all have resulted in the release of more carbon, nitrogen, and phosphorus into the environment in forms that can be taken up by living things. Extra nutrients can upset the natural matter cycles as they may accelerate the growth of some organisms beyond what would be seen naturally.
Consider the ways in which human impact is affecting the carbon, nitrogen, and phosphorus cycles.
Movement of carbon through biotic and abiotic parts of an ecosystem
Carbon cycle
What does it mean for the Earth to be energetically open but a closed system with regard to matter?
Earth receives new energy inputs but not significant new matter inputs.
Chapter 8
Ecosystems and Nutrient Cycling
Why do ecosystems need a constant input of energy? How do they deal with the fact that Earth does not receive appreciable new inputs of matter?
Ecosystems need energy and matter because there is now new resources coming in and it cant be recycled
_________ is the one-way passage ,enters an ecosystem as solar radiation and is passed along from organism to organism.
Energy Flow
Which biome description is correct?
Grasslands receive less rainfall than forests but more than deserts.
What is the purpose of photosynthesis?
It produces a form of chemical energy that the plant can use as needed
What is the NICHE of each individual?
Niche is the role a species plays in its community. How it gets energy and nutrients its habitat requirements what other species and parts of the ecosystem it interacts with.
Why is it essential that sustainable ecosystems rely on an energy source that is readily replenished, like sunlight, rather than nonrenewable sources, such as fossil fuels?
Once energy is used by an organism, it is converted to a form that is no longer useful (heat) and is therefore not considered a viable energy source for life. Any organism or ecosystem that relied on an energy source that is not readily replenished, like fossil fuels, would eventually run out.
Of the three matter cycles discussed here, the only one that does not have an atmospheric component is the __________ cycle.
Phosphorous
____needed by all organisms to make DNA and RNA and cycles very slowly
Phosphorus
A group of individuals of the same species living and interacting in the same region
Population
Chapter 9
Population Ecology
____ decompose the soils organic carbon and release it into the air as CO2
Soil microbes
Why do ecologists focus mainly on the study of populations, communities, and ecosystems?
The biosphere is too expansive to manage. SO ecologist study how ecosystems function by focusing on species interactions between individuals of the same species within a population. These relationship define the unique ecological niche of each individual species.
Plants and other producers are the only types of species that perform photosynthesis, whereas all species perform cellular respiration
True
If population is too high
can cause problems such as increased competition, fighting, and spread of disease.
Nitrogen Cycle
a continuous series of natural processes by which nitrogen passes from the air to the soil, to organisms, and then returns back to the air or soil
Biome
a portion of the biosphere(large region) characterized by a distinct climate and a certain types of plants and animals adapted to it.
Ecosystem
a specific part of the biome (earth) where living and nonliving environmental components live. (organisms and physical environment)
Reservoirs or sinks
abiotic or biotic components of the environment that serve as storage places for cycling nutrients
Community
all the populations (plants, animals, and other species) living and interacting in an area
Nitrogen fixation
bacteria convert atmospheric nitrogen into ammonia, which plants subsequently take up through their roots: consumers take in nitrogen via their diet.
living
biotic
The maximum rate at which the population can grow due to births if each member of the population survives and reproduces is
biotic potential (r)
describes population growth over time POPULATION GROWTH RATE
birth rate- death rate - the change in population size over time that takes into account the number of births and deaths as well as immigration and emigration numbers.
this is important when considering how to conserve
endangered or threatened species
Cold climates, and DRY areas
found 60 degrees North and South of the equator examples: Boreal forest, Grassland, Ice, Tundra, temperate forest, and mountains.
Hot climates, and wet areas
found on the equator and 30 degrees North and South examples: Tropical rain forest, Savannah
a population with little _________ is less able to adapt to changes and is therefore more vulnerable to environmental change.
genetic diversity
physical environment in which individuals of a particular species can be found
habitat
Temperate rain forest
has the widest range of mean precipitation and temperature range.
What does the field of ecology focus on?
how species interact with other components in their environment. (relationship)
Which of the following is the correct heirarchy of life?
individual, population, community, ecosystem, biome, biosphere
Clumped distribution
individuals are found in patches or groups within the habitat. ex. prairie dogs, elk, wolves
Random distribution
individuals are spread out in the environment irregularly, with no noticeable pattern. ex. usually species that rely on wind and water to disperse their offspring --like windblown seeds or the free-floating larvae of coral.
if population density is too low
individuals may have difficulty finding mates, the only mates may be closely related individuals which can lead to inbreeding, loss of genetic variability and ultimately extinction
