What is ecology?
the study of relationships between organisms
What do ecologists do?
Ecologists study the relationship between plants, animals and the environment
What things do ecologists study?
Population ecology, community ecology, ecosystem ecology, behavioral ecology
Example of an interaction that took place during the seed investigation
Seeds with apple juice grew mold that fed off of the juice
Hierarchy of Ecological Organization
Biodiversity
The number, and variety of living organisms in a given area, during a specific period of time; total genetic based variety of organisms
Trophic Levels of Consumers
Species Richness
the number of species in an area (ex. 3 types of grass in a field)
Species Abundance
the number of individuals per species (ex. 1 million oak trees)
Genetic Diversity
the range of different inherited traits within a species (ex. different dog breeds)
Habitat Diversity
the range of habitats present in a region (ex. desert, grasslands, oceans)
Taxonomy
how organisms are classified
Eubacteria
single-celled, no organelles (ex. E. coli, salmonella)
Eukaryota
1+ cells, have organelles (ex. fish, trees, dolphin)
Archea bacteria
single-celled, unique biochemistry, extremophiles (ex. cyanobacteria)
Viruses
NOT ALIVE - protein, not a domain (ex. COVID, flu)
Binomial Nomenclature
2-system identifying name used worldwide, "Genus species" (italicized)
Phylogenetic Tree
diagram that depicts the lines of evolutionary descent of different species, organisms, or genes from a common ancestor
Fungi
organisms that use glucose (ex. yeast, molds, mushrooms, and toadstools; separate from green plants)
Plants
organisms that create glucose through photosynthesis (ex. grass, trees)
Animals
organisms that use glucose (ex. humans, bears, tigers)
Protists
organisms that both make and use glucose; single-celled (ex. sea lettuce, kelp)
Species
A group of organisms that are closely related, who can mate to produce fertile offspring. All of the cats are feline, but each cat is a different species. "Genus species" name
Population
A group of individuals that belong to the same species and live in the same area.
Species life history
the pattern of survival and reproduction events typical for a member of the species (aka life cycle)
Habitat
Place where an organism lives
Niche
An organism's particular role in an ecosystem, or how it makes its living
Intrinsic rate of growth "r"
maximum rate of annual growth under ideal physical conditions
Population limiting factors
The reason why organisms don't reach "r" : biotic (predation, parasites/disease, competition) abiotic (weather, viruses)
Intraspecific competition
within the same species (ex. 2 wolves fighting over a dead fox)
Interspecific competition
between different species (ex. an alligator and a lion fighting over a buffalo)
Exponential Growth
J-curve, rate of growth is constantly increasing over time
Logistic Growth
S-curve, rate of growth grows then shrinks because of carrying capacity
Carrying Capacity "k"
maximum number of individuals an environment can support over a period of time; limits a population (over k = die off)
Community
A group of interdependent organisms inhabiting the same region and interacting with each other.
Symbiosis
A close relationship between two species that benefits at least one of the species
Mutualism
A relationship between two species in which both species benefit (ex. birds cleaning hippo's teeth)
Parasitism
A relationship between two organisms of different species where one benefits and the other is harmed (ex. tick on a dog)
Commensalism
A relationship between two organisms in which one organism benefits and the other is unaffected (ex. burrs) - rarest!
Resource Partitioning
the division of resources to avoid interspecific competition for limited resources in an ecosystem; each organism occupies a different niche
Population Cycles
populations rise and fall over a predictable period of time
predator population is usually less than prey population
lag time due to reproduction delay
Why are nutrients recycled in an ecosystem?
Decomposers break down dead organisms into nutrients and gases so that they can be used by other organisms
Carbon Cycle
most of carbon is stored in the atmosphere (CO2), plants absorb it and turn carbon into glucose
Why is carbon important?
Carbon has 4 valence electrons, so it’s good at bonding to make other molecules. In other words, Carbon is the building blocks for many different chemicals.
Phosphorus
Phosphorous is used to make genetic material, and help make ATP, which allows organisms to store and release energy.
Sulfur
Sulfur gives proteins structure, and the proteins make us the way we are.
Nitrogen
Nitrogen is required to make amino acids, proteins, and genetic material, which are essential to life.
Tundra biome
low temperatures, little precipitation
Desert biome
little rainfall, extremely cold or hot
Forest biome
dominated by trees; temperate forests, tropical forests, and boreal forests
Grasslands biome
dominated by grass; warm, dry climate
Aquatic biome
freshwater and marine biomes
1st Law of Energy (Conservation)
regarding quantity/amount of energy energy is neither created nor destroyed
2nd Law of Energy
regarding quality/type of energy energy changes form over time and eventually becomes unusable
Entropy
the measure of the quality of the energy in the universe any exchange of energy=waste heat and increase in entropy
Energy Flow in an Ecosystem
Energy Pyramid
A diagram that shows the amount of energy that moves from one trophic level to another in an ecosystem.
Plant Chemical Reactions
plants capture solar E
transform solar energy -> chemical energy (glucose)
Animal Chemical Reactions
transform glucose -> ATP
transform ATP -> kinetic energy (ability to move around and function)
Food Chain
hierarchical series of organisms each dependent on the next as a source of food.
Food Web
combination of all of the food chains in an ecosystem
Biomass
Total amount of living tissue within a given trophic level
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