Ecology

Question 1

what is ecology?

Answer 1

the study of interactions of living organisms with their environment

Question 2

levels of classification?

Answer 2

individual
assemblage
community
ecosystem

Question 3

what must a limiting resource be?

Answer 3

scarce and important

Question 4

what must there be for species to coexist?

Answer 4

stronger intraspecific comp than interspecific

Question 5

what is interspecific competition?

Answer 5

competition of different species for the same resource

Question 6

what is intraspecific competition?

Answer 6

competition between individuals of the same species

Question 7

what happens as populations grow?

Answer 7

they continue to grow until limiting resource where plataues and the population stops growing

Question 8

what are the three forms of competition?

Answer 8

exploitation, pre empitive and interference

Question 9

what is exploitation?

Answer 9

ability of species to use a limiting resource so the competitor cannot

Question 10

What is interference?

Answer 10

actively reducing competitor acess to limiting resource

Question 11

what is pre-emptive competition?

Answer 11

interface between exploitation and interference

prevent others using the resource e.g giant amazonian water lillies

Question 12

what is parasitism and give example?

Answer 12

host harmed and symbiont benefits

eg corpse lily - once flowers kills host

Question 13

whats commensalism?

Answer 13

host unaffected symbiont benefits - clown fish and anemone

Question 14

what is mutualism?

Answer 14

both species benefit e.g wrasse fish and parrot fish

Question 15

what happens during coral bleeching?

Answer 15

occurs when stressed and they expel zooxs which either causes the coral to die or replace the algae

Question 16

what is the relationship between coral and zooxanthelae?

Answer 16

obligate symbiosis

corals need zooxs to survive, zooxs eat algae

Question 17

what do you call the symbiont when its outside the host and inside?

Answer 17

in - endosymbiont

out - ectosymbiont

Question 18

what is coral bleaching and the problems on lizard island?

Answer 18

cyclones, bleaching event - a break up of symbiosis

Question 19

forms of physical defence against herbivory?

Answer 19

crypsis
spines
colour
raphites

Question 20

forms of chemical defence against herbivores

Answer 20

traits to attract predators

secondary metabolites

Question 21

what does nitrogen do?

Answer 21

affects nerve transmission so changing behaviour - caffine, morphine
glucosinolates - interferes with digestion -painful - comes from poison in heavy metals e.g cyanide in apple seeds

Question 22

what do terpenoids do?

Answer 22

toxic
volatile organics
eg methanol or citronella

Question 23

what do phenolics do?

Answer 23

e.g graoes

inhibt digestion by interfering with protein absorption

Question 24

adaptations for herbivores?

Answer 24

parrot fish - strong jaw
monarch butterfly eat milkweed makes them poisonous
sea slugs eat everything and get energy from alage
koalas eat eucalyptus which is poisonous but have bacteria that can break down toxins so feed babies poo so they get the bacteria too

Question 25

why are herbivores important for the ecosystem?

Answer 25

determines level of nutrients

Question 26

what do sea urchins eat?

Answer 26

algae so bloom in algal bloom

Question 27

adaptations for avoiding predation?

Answer 27

physical - giant clam strong jaw that closes when it senses movement
chemical - aposematism
masquerade
camo
behaviour - fruit bats only fly at night and rabbit fish swim in pairs so one can look out and the other can eat

Question 28

adaptations for predators?

Answer 28

speed
strength
camo
senses - Bajau adapted eyes, spleen and feet for living in water
ingestion of prey - starfish cant break through exoskeleton of coral so extract stomach and ingest it
cooperation - octopus and coral trout

Question 29

biggest predator?

Answer 29

humans

Question 30

what is the predator-prey cycle?

Answer 30

populations roughly the same but slightly offset - prey one step behind
prey>predator
when lots of prey predators increase

Question 31

whats important in the predator-prey cycle?

Answer 31

must always be equilibrium

Question 32

whats the model for predator-prey cycles?

Answer 32

lotka-volterra

Question 33

equations for lotka-volterra?

Answer 33

dH/dt = rH - alphaHL
dL/dt = betaHL - dL
where r = growth rate
alpha = rate predation
beta = probability of prey capture 
H = size of inital pop
HL = size lynx pop
dL = probability of death

Question 34

equilibrium reactions for predator-prey cycle?

Answer 34

Leq = r/alpha 
Heq = d/beta

Question 35

whats the temp range organisms survive in?

Answer 35

122 - -2

Question 36

what happens to organisms when its too cold

Answer 36

freeze and cell membranes destroyed
or freeze instantly
at -50 some organisms can survive but dormant/can’t reproduce

Question 37

whats special about lake Vostok?

Answer 37

analogue
2.2 miles under ice
if things can live here probably can live in space too

Question 38

factors influencing climate change?

Answer 38

invasive species
extinctions
over exploitations 
collapsed fish stocks 
eutrophications

Question 39

what is a homeotherm?

Answer 39

organism with small openings to conserve heat

Question 40

whats a poihilotherm?

Answer 40

organism capable of varying internal temp within a range to reproduce/grow

Question 41

what is important about chemiosynthesis?

Answer 41

means life can live in the dark

Question 42

example of an organism with antifreeze properites?

Answer 42

atlantic cod

Question 43

what is bergmanns rule?

Answer 43

the larger the organism the smaller the surface area for heat to be lost from