unit 8 bio - DEFENITIONS

Stimulus

ex/internal signal or combination of such that causes a response from an organism

signaling behaviors

produce change in behaviors of other organisms and lead to differential reproductive sucess

innate behaviors

you’re born with them → genetically aquired, no experience needed

cooperative behavior - name example

altruism → inc fitness in population

ex. team work with organisms of the same species

aposematism — example

evolved warning traits→ discourages predation

ex. markings, behaviors, and chemicals

ex. skunk arch back before sprayong

Regulation body temp: ENDOTHERMS

use thermal energy generated by metabolism to maintain body temp to maintain homeostatic body

ex. change in heart rate

Regulation body temp: ECTOTHERMS

can’t regulate their own body temp, relies on ENVIORMENT

ex. moving into/out of sun

metabolic rate - what is it? net gain vs loss?

amt of energy expended by an animal over a specific amt of time

Net GAIN → energy being stored or organisms growth

net LOSS → loss of organism mass and maybe DEATH

smaller organisms

larger organisms

higher metabolic rate

lower metabolic rate

k - selected

fewer offspring, high population density — more energy efficient, common in stable environments

r - selected

produce many offspring, lower population density — less energy efficient, common in unstable environments

Autotrophs

organisms that capture energy from physical or chemical sources in the environment

ex. photosynthetic organisms

heterotrophs

capture energy present in carbon compounds produced by other organisms

ex. metabolize carbohydrates

what triggers reproduction

photo period → being the relative length of night and day

ex. females delay implantation until october/november

population

individual organisms that interact with each other and the environment

exponential growth

a sharp increase in the growth of a population

population density

how close individuals within a population live near one another

ex. more food = dense population, less space

ex. less food = less dense population, more space

Density-dependent factors

(a)biotic factors whose affect on population size relies on a populations’ density

ex. disease, predation, terrritoriality, competition for resources

Density-independent factors

(a)biotic that affect population sice regarless of population density

ex. natural disasters

carrying capacity

max number of individuals an environment can sustain

• density (in)dependent limiting factors can cause for carrying capacity to be reached

community

group of different species living together in the same location and interacting with one another

species diversoty

refers to variety of species and wuantity of individuals of that species within a given community

ex. ocean community → one species shark(15 totak) and one species seas turtle (62 total)

species composition

identity of each species in the community

competition

an interaction that can affect how population accesses anergy and matter

Symbiosis - Mutualism

positive interaction = community change, both species benefit (+/+)

Symbiosis - commensalism

positive interaction = community change, on benefits the other isn’t harmed (+/0)

Symbiosis - Predator-prey

negative interaction = community change, one species uses the other as a food source

Symbiosis - Parasitism

negative interaction = community change, one species benefits while the other is harmed (+/-)

trophic cascade

the negative effect the removal of or decrease in a key species has on other trophic levels

niche partitioning

dec. in competition over limited resources between 2 similar species bc each species is accessing resopurces in different ways

keystone species

ares species the community structure depends on, smaller population

adaption

genetic variation that’s favored by selection