unit 8 Flashcards
how do organisms respond to the environment?
through behavioral and physiological mechanisms
stimulus
internal/external signal that causes response in organism
signaling behavior
communication can change the behavior of organisms and cause differences in reproductive success.
communication mechanisms
visual
audible
tactile
electrical
chemical signals
uses of communication mechanisms
indicate dominance
find food
establish territory
ensure reproductive success
innate behaviors
genetically controlled
learned behaviors
developed from exeriences
cooporative behaviors
Same species teamwork that inc fitness and survival of population.
examples of cooporative behaviors
aposemetism (discourage predation), scent markings by mammals
endotherms
use thermal energy generated by metabolism to maintain homeostatic body temperatures
endothermic mechanisms
change HR, fat storage, muscular contractions (shivering)
ectotherms
lack efficient internal mechanisms to regulate temp, so rely on behaviors
ectotherms mechanisms
moving in or out of the sun
there is a relationship between metabolic rate per unit of body mass and
size of multicellular organisms
metabolic rate
amount of energy to be expended by an animal over a specific amount of time
net gain in energy
energy storage/growth
net loss in energy
loss in mass and possibly deat
the smaller the organism the ___ metabolic rate
higher
reproduction strategies in response to energy availability
producing a lot of offspring at once
- less energy effecient
-common in unstable environments
producing few offspring at once
- more energy effecient
- more common in stable environments
changes in energy resources and producer level can affect
number and size of trophic levels
trophic level
position an organism occupies on a food chain
food chain
shows ONE path of energy
food webs
shows many transfers of energy between trophic levels (everything is connected)
inefficiency limits and population size ____ as you go up trophic levels
decrease