Esas chapter 2 Flashcards
Species
a group of organisms that share common characteristics and can interbreed to produce fertile offspring
Population
A group of organisms of the same species in a given area in a given time period which are capable of interbreeding
Community
A group of two or more species living in the same area at the same time
Habitat - The environment where a specie normally lives
Niche
Abiotic and biotic factors required by organisms to survive
Biotic factors
The living components of an ecosystem - how the organisms relate to other
Ecological niche
the role of a species in an ecosystem
Abiotic factors
how much space, light, air, water soil components
Ecosystem
a system made up of organisms and their physical environment and the interaction between the abiotic and biotic components
Population interactions
interaction between organisms (termed biotic)
Competition
all resources exist in limited supply so organisms compete for them - there are two types
two types of competition
1.Intraspecific competition - between members of the same spice - tends to stabilize population numbers - produces a S shaped growth curve
2. Interspecific competition - between two different species who occupy the same niche and compete for the same resources - may result in a balance in which both species share the resource or one specie can outcompete the other (becomes more dominant)
Predation
when one specie kills and consumes another
Mutualism
type of interaction where both species benefit off each other (oxpecker and wildebeest) (alarm calls)
Pathogen
an organism that causes harm to its host (bacteria, fungus, virus)
4 Biotic limiting factors
-Competition
-Finding a mate
-Predation
-Lack of food
Limiting factors
- factors that prevent a population to grow everlarge - they slow the rate of population growth as it approaches its carrying capacity
5 Abiotic limiting factors
Light
Area
Water
Temperature
Weather
4 Density dependant limiting factors (biotic)(good example of negative feedback)
Competition
Disease
Waste accumulation
Predation
4 Density independent limiting factors (abiotic)
Lack of water
Extreme temperatures
Flood
Drought
J shaped curve
Happens with bacteria because there are no limiting factors so there is exponential growth - there are booms and busts - carrying capacity is exceeding in the short term but then diebacks happen which reduce the population
S shaped curve
wolves in yellowstone - when introduced lag phase then grew fast and then stabilized at around 100 wolves)
When there are limiting factors that slow down population growth till it reaches carrying capacity
Start with exponential growth (unaffected by limiting factors)
After a certain population size the growth rate slows down
Resulting in a constant population size
1st law of thermodynamics
energy cannot be created or destroyed but it can be converted from state to state
2nd law of thermodynamics
As energy is transferred through food chains some of the chemical energy is transformed to heat energy and some of this heat energy is lost to the environment (respiration causes the most waste energy) - transfers of energy are never 100% efficient
Photosynthesis
the process by which plants convert sunlight, carbon dioxide, and water into energy and oxygen (light energy is converted to chemical energy in the form of glucose)
