C4.1 SL / HL Flashcards
Ecological hierarchy
the synergy of organisms with their environment and leads to the formation of a grouping of organisms
population
a group of individuals of the same species living and interbreeding within a given area
Transect sampling
a method used to study the distribution and abundance of organisms along a line or pathway
Random sampling
used to select a sample that is unbiased. Within each area, every part of the area must have an equal chance of being chosen. Random sampling withquadratsis used to examine differences between contrasting habitats within an habitat
sessile organisms
an organism that is anchored to a substrate and cannot move about freely
motile organisms
an organism has the capability to move under its own power
Quadrats
a frame used in ecology, geography, and biology to isolate a standard unit of area for study of the distribution of an item over a large area
Capture-mark-release-recapture
a technique used to estimate the size of a population of a particular species
Lincoln Index
a statistical measure used in several fields to estimate the population size of an animal species
carrying capacity
the maximum population size of a biological species that can be sustained by that specific environment, given the food, habitat, water, and other resources available
Limiting Factors
anything that constrains a population’s size and slows or stops it from growing
Positive feedback
output of a system amplifies the system
Negative Feedback
responds when conditions change from the ideal or set pointand returns conditions to this set point
Density-dependent factors
factors that affect the per capita growth rate of a population differently depending on how dense the population already is
Density-independent factors
limiting factors that affect the population of organisms but not restricting them to be at or within a certain number, range, or density
Lag phase
the adaptation phase for the organism where they acclimatizes themselves to the new environmental conditions provided. The growth is slow at this stage
Exponential phase
where there is a rapid increase in population growth as natality rate exceeds mortality rate
Transition phase
where the population growth slows significantly due to limiting factors
Plateau phase
Eventually the increasing mortality rate equals the natality rate and population growth becomes static. The population has reached the carrying capacity (κ) of the environment
Death Phase
population decreases as death rate is now greater than birth rate; this is usually because food supply is short
Logarithmic graphs
graphical representation that employs a logarithmic scale, diverging from the conventional linear scale used in most charts, where values are evenly spaced by creating varying intervals between values
model organisms
non-human species that scientists use in the lab to investigate and understand biological processes
Duckweed
tiny, free-floating, aquatic green plants commonly found in lentic or slowly moving water bodies, belonging to the family Lemnaceae
Community
an interacting group of various species in a common location
Intraspecific relationships
Intra-specific interactions arethose that occur between individuals of the same species, while interactions that occur between two or more species are called inter-specific interactions