AP Bio Unit 1: Ecology

ecology

the scientific study of the interactions between organisms and the environment

organisms ecology

how an organisms structure, physiology, and behavior meet the challenges posed by its environment (physiological, evolutionary, and behavioral ecology)

population

group of individuals of the same species living in an area

population ecology

analyzes factors the affect population size and why is changes

community ecology

examines how interactions between between different species affect community structure

ecosystem

community of organisms in an area and the physical factors that cause the organisms to interact, most energy through sunlight

primary producers

autotrophs, first trophic level

detrivores

organisms like prokaryotes and fungi that secrete enzymes that break down organic material (waste)

biomass

the total mass of all organisms in a trophic level

landscape (or seascape)

mosaic of connected ecosystems

net primary production

tracks the chemical energy in a food chain (gross primary production - energy the producer actually uses for CR)

eurotropication

is when the nutrients status changes from poor to rich (ex. nitrogen and phosphorus usually limit nutrients, adaptations help plants increase uptake on limiting nutrients)

trophic efficiency

the percentage of production transferred between one trophic level to the next (~10%!!!!!!!)

landscape ecology

focuses on the factors controlling exchanges of energy, materials, and organisms across multiple ecosystems

biosphere

global ecosystem, sum of all of earth’s ecosystems and landscapes

global ecology

examines how the regional exchange of energy and materials influences the functioning of organisms globally

abiotic

non-living factors

biotic

living factors

biomes

major life zones characterized by vegetation in terrestrail biomes and physical environment in aquatic biomes

climograph

plot of annual mean temperature and precipitation for a region

photic zone

the upper layer where there is sufficient light for photosynthesis.

aphotic zone

the deeper layer that receives little to no light, making photosynthesis impossible.

pelagic zone

aphotic + photic zones combined

benthic zone

the bottom of the aquatic environment, deep or shallow

benthos

organisms that live on or near the bottom of aquatic environments (in the benthic zone)

littoral zones

water close enough to the shore, shallow enough for rooted plants

limnetic zone

waters too far from the shore to support rooted plant life

thermocline

layer of abrupt temperature change that separates the warm upper layers from lower colder layers

oligotrophic

lakes that are nutrient-poor and oxygen rich often have clear water

eutrotrophic

lakes that are nutrient-rich, oxygen dense, and murky water

population density

individuals per unit of volume

dispersion

the pattern of spacing among individuals within a population

clumped

individuals stay where resources/mating is abundant

uniform

evenly spaced, result of territoriality

random

the position of one individual is different than another

survivorship curve

represents numbers in a cohort (group of individuals at the same age) still alive at each age

Type I

low death rates early to middle life, severely drops at higher ages (ex. humans, elephants)

Type II

death rate is fairly constant between children and adults (ex. rodents, lizards)

Type III

high death rates for young, flattens out for few individuals that survive the die-out

exponential growth

population growth due to an abundance of food and resources, drastic population reduction or population introduced to a new area

carrying capacity

K, maximum population size that a particular environment can maintain

logistic population growth

per capita rate that that the population growth approaches zero as the population size reaches carrying capacity

K-selected species

species with few, larger offspring, raised by parents (significant energy investment), most survive, slow growth rate

r-selected species

species with many small offspring, minimal parental care, more energy efficient

density dependent limiting factors

limiting factors that become more restricting as population size increases (competition, disease, predation, etc.)

density independent limiting factors

limiting factors that affect the population randomly and do not depend on the size of the population (natural disasters, human impact, climate change)

community

populations of different species living in close enough proximity to act as a biological community

competitive exclusion principle

two species who compete for the same limiting resources

G.F. Gause’s experiment

grew aurelia and caudatum apart = thrived, together = caudatum extinct

ecological niche

position that a species occupies in its ecosystem, including all the interactions and roles it fills (sets of biotic and abiotic resources an organism uses)

fundamental niche

ideal/theoretical. pre-competitive, no limiting factors

realized niche

actual, post-competitive, limiting factors present, species coexisting

cryptic coloration

camouflage, makes prey harder to see

aposematic

warning coloration (poison dart frog)

Batesian mimicry

protected by resembling other species (nonvenomous snake resembles venomous one)

herbivory

animal eats part of a plant, haring it, but not killing it

visual cues

animals use sight to detect predators/ changes in environment

auditory cues

animals use hearing to detect changes in environment

physical cues

animals use movement or touch to detect changes in environment

chemical cues

animals use pheromones to send chemical signals (food, mating, etc.)

phototrophic cues

animals use response to light/dark (circadian rhythms)

competitive interactions

competition for food between members of the same or different populations, (-/-)

symbiotic interactions

long term biological interactions between members of different species or populations

predation

predators hunt and kill their prey, herbivores eat plants to get energy, (+/-)

parasitism

relationship where one organism exploits the other for food/nutrients, host is HARMED, not KILLED (reproductive parasites usually kill host) VERY slight decrease in population for host, inc. for parasite, (+/-), tapeworms

mutualism

both species cooperate and gain an advantage (+/+), pollinators

commensalism

on organism benefits while the other is not harmed or helped, (+/0)

species diversity

variety of kinds of organisms in a community (higher diversity = can recover from environmental stress)

keystone species

exert strong control on community structure by pivotal ecological roles (i.e. starfish eats competitively dominant mussels)

ecological succession

changes in a species that occupy a certain area after a disturbance

primary succession

when ecological succession occurs in a lifeless area (volcano)

secondary succession

recolonization of an area after a major disturbance

latitudinal gradients

affect species richness through evolutionary history and climate

species richness

greatest when there is more diversity, sunlight, precipitation, and evapotranspiration (evaporated water from soil and plants)

pathogens

disease-causing microorganisms and viruses

zoonotic pathogens

pathogens transferred form animals to humans

Lyme disease

spread by zoonotic pathogens to the human host from the vector (tick)