Biology Ch 3

The branch of biology dealing with interactions among organisms and between organisms and their environment is called
Ecology
the combined portions of earth in which all living things exist is called the
Biosphere
All of the members of a particular species that live in one area are called a
Population
Which if he following descriptions about the organization of an ecosystem is correct
Species make up populations, which make up communities
The simplest grouping of more than one kind of organism in the biosphere is
A community
Which of the following is NOT a basic method used by ecologists to study the living world? Experimenting, classifying, modeling or observing?
Classifying
Which ecological inquiry method is an ecologist using when He or she enters an area periodically to count the population numbers of a certain species
Observing
Plants are
Producers
What is he original source of almost all the energy in most ecosystems
Sunlight
The algae at the beginning of the food chain in figure 3-1are
Producera
An organism that uses energy to produce its own food supply from inorganic compounds is called a
Autotroph
Which of the following organisms does not require sunlight to live?
Chemosynthetic bacteria, algae, trees or photosynthetic bacteria
Chemosynthetic bacteria
An organism that cannot make its own food is called a ?
Heterotroph
Organisms that obtain nutrients by breaking down dead and decaying plants and animals are called
Decomposers
What is an organism that feeds only on plants called
Herbivore
All the interconnected feeding relationships In an ecosystem make up a food
Web
The total amount of living tissue within a given tropic level is called the
Biomass
What animals eat both producers and consumers
Omnivores
A snake that eats a frog that has eaten an insect that fed on a plant is a
Third-level consumer
The tropic levels k. Figure 3-2 illustratw
The relative number of individual organisms at each level
Only 10 percent of the energy stored in an organism on be passed on to the next tropic level. Of the remaining energy, some is used for the organism’s life processes, and the rest is
Eliminated as heat
Which type of pyramid shows the amount of living tissue at each tropic level in an ecosystem
Biomass pyramid
The repeated movement of water between earths surface and the atmosphere is called
The water cycle
What is the process by which bacteria convert nitrogen gas in the air to ammonia
Nitrogen fixation
Carbon cycles through the biosphere in all of the following processes except
Photosynthesis, transpiration, burning if fossil fuels or decomposition of plants and animals
Transpiration
Nitrogen fixation is carried out primarily by
Bacteria
Organisms need nutrients in order to
Carry out essential life functions
The movements of energy and nutrients through living systems are different because
Energy flows in one direction and nutrients recycle
The rate at which organic matter is created by producers in an ecosystem is called
Primary productivity
Which is most likely to be a limiting nutrient in a freshwater pond?
Phosphorus