Ecology Study Guide Flashcards
What is ecology the study of?
Is the study of interactions between organisms and their environments. Produce a web of interdependence.
What is homeostasis? Give an example?
Relatively constant internal physical and chemical conditions that organisms maintain. Example: body temperature.
What are the three methods used to study ecology?
Observations, Experimentation, and Modeling
Give 2 examples of biotic factors in a pond
Algae and frogs
Give two examples of abiotic factors in a pond
water and temperature
Define predation
One animal (the predator) captures and feeds on another animal (the prey).
What is a niche?
The range of physical and biological conditions in which a species lives and the way the species obtains what it needs to survive and reproduce.
What is a carnivore?
An organism that mostly eats meat, or the flesh of animals. They are consumers.
What is a herbivore?
An animal (herbivore) feeds on producers (plants). It is a consumer.
Define competition
When organisms try to obtain the same limited resource, competition is created.
What are the 2 types of competition?
Interspecific: Different species compete for the same resources.
Intraspecific: Members of the same species compete for the same resources.
What does the competition exclusion principle state?
No two species can occupy exactly the same niche in exactly the same habitat at exactly the same time. Competition would be created and one species will be better at competing for the resource and the other species would die off.
Define symbiosis
A relationship in which two species live closely together.
Mutualism
A relationship between two species that mutually benefits both organisms.
Example: Sea Anemone and Clownfish
Parasitism
A relationship in which one organism lives inside or on another organism and harms it. One organisms benefits and the other is harmed.
Examples: Tapeworm in intestines, fleas on dogs, leeches
Commensalism
A relationship between organisms that benefits one but neither helps nor harms the other.
Example: Barnacles and Whales
What is the difference between primary and secondary succession?
Primary succession occurs in an environment without previous life, or a barren habitat. No soil exists. Completely destroyed and empty. Secondary succession occurs in an area that had previously been inhabited but experienced a disturbance, such as a wildfire. Soil survives. Although most of the ecosystem is destroyed, some parts survive and can begin to regenerate.
What would cause primary succession to occur?
Volcano eruption and glaciers.
What would cause secondary succession to occur?
Hurricane, wildfire, deforestation.
What is an example of a human caused disturbance in the environment?
Deforestation, forest fires, farming/logging
What is a pioneer species?
The first species to colonize barren area. Lichen and moss. It breaks down rock and adds organic material to form soil.
What will you find in a climax community?
Secondary succession in healthy ecosystems following natural disturbances often returns to the original climax community.
The final stage of succession.
A stable mature community which has reached equilibrium.
What is a keystone species?
A keystone species is a plant or animal that plays a unique and crucial role in the way an ecosystem functions. A keystone species disappearance would start a domino effect and other species in the habitat would also disappear and become extinct.
Biosphere
All life on Earth
Biology
study of life
Characteristics of Life
Living things are made up of cells, Living things are based on an universal genetic code, Living things reproduce , Living things grow and develop, Living things obtain and use materials & energy , Living things respond to their environment,
Living things maintain a stable internal environment
Living things change over time
Stimulus
a signal that causes an organism to respond.
Sexual reproduction
cells from two parents unite to form the first cell of a new organism
Metabolism
building up or breaking down materials to carry out life processes.
Asexual reproduction
one organism can produce identical copies of itself
Unicellular
one celled.
Multicellular
many celled.
Sexual reproduction
blending of parent DNA.
DNA(Heredity)
Deoxyribonucleic Acid.
Asexual reproduction
“clone” of parent.
Levels of Organization
Individual
Population
Community
Ecosystem
Biome
Biosphere
Individual
A species that can breed and produce fertile offspring.
Population
A group of the same species living in the same area.
Community
A mix of different populations of species living in the same area.
Ecosystem
All the organisms that live in a place with their environment.
Biome
Our entire planet.
Biosphere
Groups of ecosystems that have similar climates and organisms.
Tolerance of a Species
It is the ability to survive and reproduce in their environment. If that condition is beyond the limits of tolerance, the organism cannot survive.
A species’ tolerance will determine what habitat the organism will live in.
Ecological Succession
The series of predictable changes that occur in a community over time is called ecological succession.
What four factors do researchers investigate when studying a population?
Growth Rate, Age Structure, Geographic Range, and Population Distribution/Density
What is the difference between density and distribution?
Population density means the number of individuals per unit area. Distribution refers to how the population is spaced out across the range.
What are the three types a population can be distributed?
Random, Uniform, and Clumped.
What are four ways a population can change in size?
Birth Rate & Death Rate
If the birthrate of a species is higher, then the death rate, the population will increase.
If the birthrate is lower then the death rate, the population will decrease.
Immigration & Emigration
When species move into a population. (INTO)
When a species moves away from a population. (EXIT)
What is exponential growth? What type of curve does it create when plotted?
Unlimited resources (unlimited food, space, and reproduction partners), a population will grow exponentially.
The size of each generation of offspring will be larger than the generation before it.
Population size starts off small and slowly rises.
Rises faster.
J-shaped Curve
Explain the 3 phases of logistic growth. What type of curve does it create when plotted?
Logistic Growth
A population’s growth slows and then stops, after a period of exponential growth.
S-shaped Curved
Population size increases rapidly, Rate of population slows down, Rate of population growth stops
Population levels off
What is an environment’s carrying capacity?
The maximum number of individuals of a particular species that a particular environment can support.
What are some of the effects if the carrying capacity of an environment is exceeded?
If a population exceeds carrying capacity, the ecosystem may become unsuitable for the species to survive. If the population exceeds the carrying capacity for a long period of time, resources may be completely depleted. Populations may die off if all of the resources are exhausted.
What is a density dependent limiting factor?
Only affect strongly if a population reaches a certain number of organisms per unit area. Parasitism & Disease. It is density-dependent because it can spread easily through an overpopulated area.
Name a density independent factor
Will affect all populations regardless of population size and density.
Examples:
Flooding.
Wildfires.
