organisms and populations Flashcards
4 levels of ecological organisation
organism population community biome
niche is a
range of conditions in which an organism can live, use resources and perform a distinct functional role
which is the most ecologically important abiotic factors
temperature and water
significance of temperature on the organisms
has an affect on metabolic and physiological activity; enzymes and kinetics
____ can tolerate narrow range of temp
stenothermal eg: snake
_____ can tolerate high range of temp
eurythermal eg: human
life on earth is unsustainable without ____
water
for aquatic organisms, _____ of water is important
quality: pH, chemical composition, salt content
inland water salinity
less than 5 ppt
seawater salinity
30-35 ppt
hypersaline lagoon
more than 100 ppt
freshwater fishes cannot live long in sea because
osmotic problems they would face
light is important for
photosynthesis, photoperiod
algae which lives in deep ocean
red algae
light importance for animals
diurnal rhythms, duration and cues for migratory activities
____ quality of sunlight is important
spectral quality
soil characteristics
pH, particle size, composition
_____ determines the type of benthic organism that can thrive in deep sea
sediment characteristic
____ can maintain body temperature and osmotic balance
regulators
the process of maintaining the internal balance is called
homeostasis
the success of mammals is because of the ability to
regulate and maintain constant body temperature
normal body temperature is
37
cold response:
shiver
heat response
sweat
99% of animals and all plants are _____
conformers
thermoregulation is energetically ______
expensive
why are shrews/ small animals not found in polar regions
heat loss or gain is a function of surface area. small animals have large body volume and small surface area and therefore heat is quickly lost and have to expend much energy to generate heat
partial regulation involves
migration and suspension
Siberian crane move from
Siberia to keolado national park in bharatpur Rajasthan to escape harsh winter
suspension in bacteria, fungi and lower plants
spore formation
zooplankton suspend by
diapause
seeds suspend germination by
dormancy
winter sleep
hibernation
summer sleep
aestivation
____ is any attribute of an organism that allows it to thrive in an area
adaptation
kangaroo rat is found in
north american desert
kangaroo rat adaptation:
fat oxidation for water, uric acid excretion
xerophyte adaptation
thick cuticle, leaf modified into spine, scotopic stomata, advanced root system, phyllode
allen’s rule
polar animals have short ears and legs, blubber for fat insolation
in high altitude, body compensates for low oxygen by
increasing RBC production, breathing rate and decreasing the binding affinity of hemoglobin
archaebacteria adaptation
thermostable enzymes
desert lizard adaptation
behavioural, bask in sun for heat and move to shade for cool
population attributes
size, age ratio, sex ratio
population is a group of organisms __
live together, use same resources and potentially interbreed
factors affecting population density
natality, mortality, immigration, emigration
population density equation
N(t+1) = N(t) + (B+I) - (D+E)
exponential growth occurs when
resources are unlimited and population recognizes its innate ability to increase in size- darwin
exponential growth equation
dN/dt = rN
intrinsic rate of natural increase is r =
r = b-d (natality - mortality)
norway rat intrinsic rate is
0.015
flour beetle intrinsic rate is
0.12
1981 indian population intrinsic rate is
0.0205
logistic growth equation
dn/dt = rN (K-N/K)
conduit for energy flow
predation
reproduce once in life
bamboo, salmon
reproduce many times
mammals
large number of small sized offspring
oyster, pelagic fish
____ in Australia introduced in 1920s spread across millions of hectares of rangeland, controlled by ___
prickly pear cactus, natural predator moth
in north american pacific coast, starfish pisaster removed ____
killed 100 species of invertebrates due to competition
example of predation
cactus, pisaster
calotropis protection by
cardiac glycosides
____- % of all insects are ___
25% phytophagous
competition examples
flamingo and resident fish, abingdon tortoise and goat, balanus and chathalamus
competitive exclusion by
gause
connell’s field experiment
balanus and chathalamus; competitive release
mc arthur warbler
resource partitioning