biology chapter 14 Flashcards
ecology
is the study of the interactions between organisms and their environment
abiotic
physical environment which includes climate, temperature, availability of ight and water and the local topology
biotic
all living things which directly or indirectly influence the life of the organism including the relationships that exist between organisms
organism
is the individual unit of an ecological system, but the organism itself is composed of smaller units.
population
is a group of organisms of the same species living together in a given location
species
is any group of similar organisms that are capable of reproducing
community
consists of populations of different plants and animal species interacting with each other in a given environment
ecosystem
encompasses the interaction between living biotic communities and the non living environment
biosphere
includes all portions of the planet which support life– the atmosphere, the lithosphere (rock and soil surface) and the hydrosphere (the oceans)
water
is the major component of the internal environment of all living things. May be readily available or the organism may possess adaptations for storage and conservation of water
temperature
must be maintained at an optimal level
sunlight
is the ultimate source of energy for all organisms
photic zone
the top layer through which light can penetrate & where all aquatic photosynthetic activity takes place
aphotic zone
only animal life and other life that does not require photosynthesis exist
substratum
determines the nature of plant and animal life in the soil. Soil is affected by acidity, texture, minerals, and humus
texture
determine the water holding capacity of the soil
loams
contain high percentages of each type of soil
minerals
affect the type of vegetation that can be supported
humus quantity
determined by the amount of decaying plant and animal life in the soil
niche
defines the functional role of an organism in its ecosystem
habitat
is the physical place where an organism lives
extinction
one species may be competitively superior to the other and drive the second
autotrophs
are organisms that manufacture their own food
heterotrophs
cannot synthesize their own food and must depend upon autotrophs or other heterotrophs in the ecosystem to obtain food and energy
herbivores
are animals that consume only plants or plant foods
symbiotic bacteria
capable of digesting cellulose inhabit the digestive tracts of herbivores and allow the breakdown and utilization of cellulose
carnivores
are animals which only eat other animals. Possess pointed teeth and fang like canine teeth for tearing flesh. They have shorter digestive tracts due to the easier digestibility of animal food
omnivores
are animals which eat both plants and animals
integrated system
which are dependent upon one another for survival
obligatory
one or both organisms cannot survive without the other
commensalism
one organism is benefited by the association and the other is not affected. The host neither discourages nor fosters the relationship
mutualism
a symbiotic relationship from which both organisms derive some benefit
parasitism
benefits at the expense of the host. Flourishes among organisms such as bacteria, fungi, and animals
ectoparasites
some parasites cling to the exterior surface of the host using suckers or clamps
endoparasites
live within the host
predators
are free living organisms which feed on other living organisms
saprophytism
include those protists and fungi that decompose (digest) dead organic matter externally and absorb the nutrients; they constitute a vital link in the cycling of material within the ecosystem
scavengers
are animals which consume dead animals. Require no adaptations for hunting and killing their prey
interspecific
relations between species
osmoregulation
animals have developed many adaptations for maintaining their internal osmolarity and conserving water
salt water fish
live in a hyperosmotic environment which causes them to lose water and take in salt. They are constantly in danger of dehydration and must compensate by constant drinking and active excretion of salt across their gills
freshwater fish
live in a hypoosmotic environment which causes intake of excess water and excessive salt loss. These fish correct this condition by seldom drinking, absorbing salts through the gills and excreting dilute urine
poikilothermic
cold blooded and most of their heat escapes to the environment
homeothermic
are warm blooded.
producers
they utilize the energy of the sun and simple raw materials (carbon dioxide, water, minerals) to manufacture carbohydrates, proteins and lipids. Always form the initial step in any food chain
primary consumers
are animals which consume green plants (herbivores)
secondary consumers
are animals that consume the primary consumer (carnivores)
tertiary consumers
these are animls that feed on secondary consumers
decomposers
include saprophytic organisms and organisms of decay (which include bacteria and fungi).
pyramid of energy
each member of a food chain utilizes some of the energy it obtains from its food for its own metabolism (life functions) and loses some additional energy in the form of heat
pyramid of mass
since organisms at the upper levels of the food chain derive their food energy from organisms at lower levels, and since energy is lost from one level to the next, each level can support a successively smaller biomass
pyramid of numbers
consumer organisms that are higher in the food chain are usually larger and heavier than those further down. Since the lower organisms have a greater total mass, there must be a greater number of lower level organisms
material cycles
material is cycled and recycled between organisms and their environment, passing from inorganic forms to organic forms and then back to the inorganic forms
nitrogen cycle
since there is a finite amount of nitrogen on the earth, it is important that it be recovered and reused
climax community
is the stable, living (biotic) part of te ecosystem described above in which populations exist in balance with each other and with the environment. They type of climax community depends upon all the abiotic factors: rainfall, soil conditions, temperatures, shade, etc.
ecological succession
is the orderly process by which one biotic community replaces or succeeds another until a climax community is established
sere
each community stage
dominant species
the one that exerts control over the other species that are present
physical factors
temperature, nature of the soil, rainfall, etc
climax vegetation
is the vegetation that becomes dominant and stable after years of evolutionary development
desert biome
receive less than ten inches of rain each year. Growing season in the desert is restricted to those days after rainfalls. Most desert plants conserve water actively. Desert animals live in burrows.
grassland biome
grasslands are characterized by a low rainfall. Provide no shelter for herbivorous mammals from carnivorous predators.
tropical rain forest biome
rain forests are “jungles” characterized by high temperatures and torrential rains. Trees grow closely together; sunlight hardly reaches the forest floor.
temperate deciduous forest biome
have cold winters, warm summers and a moderate rainfall.
temperate coniferous forest biome
these forests are cold, dry, and inhabited by fir, pine , and spruce trees. Much of the vegetation has evolved adaptations for water conservation such as needle-shaped leaves
taiga biome
receive less rainfall than the temperate forests, have long cold winters, and are inhabited by a single coniferous tree-the spruce
tundra biome
the tundra is a treeless, frozen plain found between the taiga lands and the Northern ice-sheets. There is only a very short summer and, thus, a very short growing season during which time the ground becomes wet and marshy
polar region
the polar region is a frozen area with no vegetation and terrestrial animals. Animals that do inhabit polar regions generally live near the polar oceans
marine biomes
contain a relatively constant amount of nutrient materials and dissolved salts
intertidal zone
region exposed at low tides which undergoes variations in temperature and periods of dryness. Populations in the intertidal zones include algae, sponges, clams, snails, sea urchins, starfish, and crabs
littoral zone
region on the continental shelf which contains ocean area with depths up to 600 feet and extends several hundred miles from the shores. Populations in littoral zone regions include algae, crabs, crustacea, and many different species of fish
pelagic zone
is typical of the open seas and can be divided into photic and aphotic zones
photic zone
the sunlit layer of the open sea extending to a depth of 250-600 feet. It contains plankton; passively drifting masses of microscopic photosynthetic and heterotrophic organisms, and nekton; active swimmers such as fish, sharks, or whales which feed on plankton and smaller fish. the chief autotroph is the diatom, an algae
aphotic zone
the region beneath the photic zone which recieves no sunlight. There is no photosynthesis in the aphotic zone and only heterotrophs exist here. Deep sea organisms in this zone have adaptations enabling them to survive in very cold water, with high pressures, and complete darkness. the zone contains nekton and benthos (the crawling and sessile organisms). some are scavengers and some are predators. the habitat of the aphotic zone is fiercely competitive
