Bio Ecology And Plant Repro (missing Case Studies) Flashcards
Abiotic vs biotic environment
Physical factors , living things organisms interact with
Abiotic enviro factors
- light intensity
- temp
- pH
- salinity
- oxygen
- water
Abiotic: light intensity
- affects distribution and growth of plants and animals
- growth of certain plants affects animal distribution
Abiotic temperature
- affects physiological and metabolic activities of organisms : affects rate of reaction of enzymes
- eg snakes hibernate in winter: lower rate of enzymes reactions
Abiotic: pH
- Most organisms survive a range of oH
- acidophiles: microorganisms that thrive in acidic conditions
- eg blueberry and orchids prefer acidic soils
Abiotic: water
- availability factors: amt and pattern of rainfall, air humidity
- need water to live; where water is scarce, orgs adapted for survival
Abiotic: oxygen
- needed for aerobic respiration
- eg mangroves roots in oxygen poor mud, thus breathing roots that project above mud surface
Abiotic: salinity
Eg fish
Freshwater: salt loss, excess water. Uptake of salt in gills, kidney reabsorbs more salt, dilute urine
Saltwater: water loss, excess salt. Seawater absorbed in intestines, kidney excretes little salt, conc urine
Energy and nutrient flow P-C-D
Producers
Convert light e from sun into Chem e in food
Consumers
Obtain e by feeding on other orgs
decomposers
Obtain e by breaking down dead orgs, faeces, excretory products. Releases inorganic nutrients (carbon, nitrogen)
Food chain
Series of orgs thru which energy is transferred in the form of food
Grass ββ-> grasshopperβ> toad ββ¦
(Producer) (pri cons) (Sec cons)
Food web
Consists of interlinked food chains
. β> caterpillar ββββ
. | v v
Green plant β> grasshopperβ> spider
. | ^
. β> aphid ββββββ-
βββ> ladybug
Non cyclic energy flow
- sun is main source
- light e to Chem e by producers via photosynthesis
- energy from lvl to other via feeding
- energy lost: heat (respiration), uneaten parts, dead bodies, faeces
Pyramid of numbers
No of organisms at each trophies level
(Can be inverted if orgs are parasitic/ many small on large)
. __
. _______
_________
Pyramid of biomass
Comparison of mass of orgs (dry mass: mass of dead, dry body)
May look odd if one org has high repro rate
Pyramid of energy
Total energy in each tropic level
- energy lost to surroundings as food transferred from one tropic lvl to another
- approx 90% e lost from each tropic level
Loss of energy to environment when passing thru tropic levels
- heat during respiration
- uneaten body parts
- undigested matter egested
- waste products excreted
Nutrient cycling
- brought about by physical, chemical, and biological processes
- involves both biotic and abiotic
The carbon cycle
The carbon cycle
- carbon continuously removed and released into Atmos as CO2
- relatively consistent CO2 conc (~0.03%)
Importance: - ensures continuous supply for photosynthesis
- enables energy flow thru ecosystem
Carbon cycle co2 removal
Photosynthesis
- green plants take in CO2, used to prod carbon compounds
- feeding: carbon compounds stored in animals bodies
- fossil fuel: carbon compounds may be preserved
Carbon cycle co2 released 3
Respiration
- carbon compounds eg glucose broken down into co2
Combustion
- fossil fuels release co2
Decomposition
- organisms die, dead matter broken down into simple substances eg co2 by decomposers
Carbon sinks (oceans and forests)
Area that stores carbon conoides for indefinite period, stores more than releases
Oceans:
- largest CS on earth
- co2 dissolved in water and used by phytoplankton and algae in photosynthesis
- portion buried in seabed as fossil fuels
Forests:
- co2 in Atmos absorbed by plants for p.sis
- large and of carbon compounds stored in trees
- remains for dead trees form coal (fossil fuel)
Renewable vs non renewable natural resources
can be replaced by natural cycles if not overused , cannot be replaced