Chapter 3 - Physical conditions and the avaliability of resources (CHAPTER + SLIDES) Flashcards
slides notes are included!!
Conditions
Physiochemical features of the enviornment
- temperature, humidity, pH, salinity
- an organism can alter conditions in its immediate enviornment
- are not consumed or used up
Resources
Consumed by organisms in their course of their growth and reproductions
- organisms may competed with eachother for resources
Extreme conditions
only appear ‘harsh’, ‘benign’ or ‘extreme’ to us as humans, but are completely normal for the organism.
Effects of conditions
Creates response curves!!!
y axis = performance of the species
x axis = intensity of the condition
1) Temperature, pH, salinity, moisture
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2) Usually poisons such as concentration of arsenic
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3) Toxic at high levels but required for low levels
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Have three lines on the graph, upmost represents reproduction, the middle represends individual growth, and the last is for individual survival
Final size of an organism
Rates of growth + development determine its final size
Temperature for example will affect the final size as it impacts the performance of the species at varying intensities. (This can be used to predict what effect global warming may have on us)
Thermophiles
Love the heat. 60°C ≤
Chilling injury
Extended periods of inactivity due to the cold
- leads to cell membrane breakdown
- the timing and duration of the temperature exposure is important.
Rates of physical processes
Can be modulated by conditions
Photoperiod
Length of the period of daylight within the daily cycle
- example: birch treese
Diapause
Getting ready for winter / slowing down the development of the body. (Typically an insect)
Acclimitization/Acclimation
Altered response to more extreme conditions.
- example: faster metabolism, antifreeze, etc.
Acclimation is the same thing but scientific not natural
Motile animals
Move
Decidiuous
Annual shedding
Sedentary animals
dont move, they stay
Conditions effects on organism
An organism will sufer if its food is another species that cannot tolerate an enviornmental condition.
- example: rush moths need a flower.
A condition can increase/impact the development of disease
- example: fungal spread / parasitic growth / high or low temperatures.
A condition can also increase or decrease competition.
Physical conditions follow a seasonal cycle
Organisims can therefore change and anticipate whats gonna come by acclimating.
Endotherms
Body temperature regulated by an internal mechanism
- good for a bigger temperature range
- is independent to enviornmental conditions, but has a high food requirement
Ectotherms
Body temperature is determined by the enviornment
Intermediate forms
Endo/Ectothermics dont have absolute distinction. Some intermediate forms are present
- tunas and sharks
- hamsters hibernate despite being endothermic so they lower their temp.
You wont find small aquatic endotherms
You wont find large terrestrial ectotherms
(komodo dragon biggest)
Poikilotherms
Have variable body temperature
Homeotherms
Maintain constant body temperature
Endothermic adaptations
For the cold
- small limbs (low surface area to volume
- dense fur
- feathers or fat
For the hot
- long limbs (to dissipate heat better)
- thin fur
- long ears
Seasonal temperature effects
Temperatures that very seasonally can create annual changes or dedications such as hibernation
Acidophilic
Loves acidic enviornments