Exam 2 Flashcards
Predation
one organism kills and more or less consumes another organism
oscillating pattern between predator and prey
+ and - interaction
Parasitoidism
predator lays egg in another organism killing the host
+/-
Herbivory
organisms consume autotrophs such as plants, algae, bacteria
Parasitism
living as parasite on or in another organism not killing host
+/-
Numerical response of predation
Increase in prey causes increase in predators through increased reproduction
aggregative response of predation
predator attracted to areas of high prey density
leads to negative effect on predator
Also leads to areas of low prey density not being preyed on and prey densities increasing
What do the lynx and hare predation graphs show
Long term cycles in population density
functional response
relationship between predator’s feeding rate and prey density
predator will take more prey as prey density increases
Type 1 functional response
Number of prey taken/ predator increases linearly to maximum as prey density increases
less common
Type 2 functional response
number of prey taken/predator rises at decreasing rate toward maximum value
most typical
Type 3 functional response
number of prey taken/predator is low at first, then increases in sigmoidal fashion (S curve) and pleateaus where attack rate remains constant
Optimal foraging theory
animal minimizes cost/benefit=energy expended/energy consumed
Batesian mimicry
A harmless prey mimicks a dangerous prey
What must occur for Batesian mimicry to work
Needs to be more of the harmful species
There has to be a learned response between harmful prey and predator first
Mulerian mimicry
Both species that look alike are harmful
Often closely related
Doesn’t matter which is more abundant
Defense mechanisms in plants
Milkweek, cellulose, tannins, tobacco
Parasite
organism that obtains nutrients from one or more hosts usually not causing death directly
Ectoparasite
External to host
Sealambre, vampire bats, ticks, lice
Ectoparasite effects
Hosts that are closely related share closely related ectoparasites
More parasite= lower life expectancy of host, longer time to lay eggs, lower reproduction potential
Endoparasitism
Internal to host
tapeworm, flukes, protozoans
vector
organism that transmits the disease-causing agent
transfers parasite to host
Host
Organism that is affected by disease causing agent
Intermediate host
Organism that is required in life cycle of parasite but not affected
Reservoir
Organism with the parasite is not affected and not required for life cycle of parasite
Schistosomiasis
Snails carry the parasitic worm where it develops
parasite released into water
parasite penetrates human skin
Bancroftian filariasis
Roundworm plugs lymphatic system
vector- mosquito
ivermectin effective preventative
Onchocerciasis - river blindness
vector: black fly that must breed in streams
Sleeping sickness
African Trypanosomiasis- parasite
Vector: Tse-tse fly
Injects saliva in human preventing clotting and introducing pathogen
Chagas disease
American Trypanosomiasis
vector: kissing bug
Transmits through feces
Leishmaniasis
Vector: sand fly
Malaria
Trypanosoma
vector: Mosquito females inject saliva
Mosquito is intermediate host
Bot fly
Endoparasite
lay eggs on mosquitos and when attach to humans, heat allows eggs to lay and hatch inside human
Mutualism effect
+ / +
both benefit
Commensalism effect
+ / 0
one benefits the other not affected
parasitism and parasitoidism effect
+ / -
one benefits one is harmed
amensalism effect
0 / -
one harmed one not affected
examples of how parasites change host behavior
malaria infection creates scent more attractive to mosquitos
taxoplasmosis infected mouse makes it lose fear of cats
flukes in fish make them more visible to birds
gordian worm makes cricket drown itself
how ants and bullhorn plant show mutualism
bullhorn tree gives habitat and nutrients
Ants give protection to plant from other insects and plants
rhizobium and legume mutualism
plant given nitrogen for growth
mycorrhizae and plant root mutualism
mycorrhizae give plant nutrients
plant gives sugars and products of photosynthesis to fungi
in unfertilized soil with mycorrhizae, there is less above ground plant growth
lichen mutualism
fungus provides nutrients to algae and algae provides energy to fungus
ruminants in cows
cows regurgitate and chew food repeatedly to increase surface area of bacteria in stomach to allow it to digest cellulose
condition
abiotic environmental factor varying in space and time and to which organisms respond differentially
Temp, humidity, pH, water flow rate
resource
factors that organisms may use up and make less available to others
Nitrogen, light, space
Homeotherms
constant body temperature
Poikilotherms
variable body temperature
Endotherms
generate heat internally
ectotherms
heat comes from the environment
Hibernation v estivation
Hibernation: response to cold
estivation: response to heat and drought
Diapause
response to combined effects of temperature and photoperiod (day light cycle)
Form of hibernation for insects where they delay development with unfavorable conditions
Behavioral thermoregulation
move to different areas to keep body temp constant
adaptations in ectotherms that allow them to survive
desert plant: reflective leaves, orient leaves parallel to be away from the sun
Arctic plant: parabolic shape directs heat to the center of flower, move flower towards sun, dark leaves , perpendicular leaves
low temperatures in ectotherms
low activity, feeding, slower escape from predation
belowe freezing they produce antifreeze
high temps in ectotherms
enzyme denaturing, dehydration, plant starvation
physiological time degree day
Insect and some reptile growth can stop until it gets warm enough
degree day calculation
Multiply temp by however many days it is held constant
How plants can be endotherms
Skunk cabbage raise temp by translocating starch to metabolize it to generate heat
Ectotherm advantage
Low cost- not energentically expensive
More of what it ingests can be used for growth because the energy isn’t directed to heat
Endotherm advantage
Exploit wider variety of habitats
El Nino
Winds blow from east to west moving surface water west meaning warm water piles up on western side of ocean
cooler water on eastern side of ocean near south america
How el nino is measured
SOI measured barometric pressure in Tahiti - Darwin
Strong negative values - el nino
Strong positive values- La nina
Thermocline
Separates warm (above) and cold water (below)
El Nino Effects
Ecosystem collapse
Economic collapse
Droughts in Australia, Africa, South America
Wet in America, northern Europe
Warmer weather, less ice cover on lakes
El Nino Great Salt Lake effects
Less salinity, more phytoplankton and chlorophyll
grazers cause competitive release
Soil
Mixture of inorganic materials (clay, silt, pebbles, sand), decaying organic materials and living organisms
Roles of soil
- ecosystem
-plants
-animals
-decomposers
Ecosystem- nutrient delivery system, recycling system, waste disposal system
plants- site of germination, support, nutrients, decay
animals- refuge, sewer, complete habitat
decomposers- resource to break down waste
Soil layers
O Horizon
A horizon
E horizon
B Horizon
C Horizon
R- bedrock
O horizon
surface litter with freshly fallen leaves, organic debris, easily fragmented
A horizon
Topsoil; living organisms, inorganic materials, humus: partially decomposed organic matter ceated by humification holding on to cations and retains nutrients for plants
Cation Exchange Capacity (CEC)
Total negative charges within humus that retain plant nutrient cations and lower valence ions
E Horizon
Leaching zone where suspended materials move downward
B horizon
Subsoil where there is an accumulation of iron, aluminum, humic compounds, and clay that has been leached down
C horizon
Parent material : partially broken down inorganic materials
Porosity
Number of pores per unit of soil, percentage of empty space
high porosity= low holding capacity for water
Permeability
Determined by size of pore
How well water passes through
high permeability= larger pores, water moves through easily
What do porosity and permeability determine
water holding capacity
aeration
susceptibility to erosion
CEC
workability
Formation of soil
Weathering
- hot, cold weather
- rain, wind breaking up parental material
Tundra
Gleization
O horizon main layer
Coniferous
Podzolization
Acid litter- mor humus
fungi decomposers
Deciduous
Podzolization
Less acid litter- mull humus
bacteria decomposers
Grassland
Calcification
less leaching
Tropical rain forest
Laterization
Barely present O horizon - high decomposition, weathering
