bio C4

population

organisms of the same species lving together that can interbreed

sample

measuring some subset of a poopulation

standard error

use for hypothesis testing when you compare means and declare a difference between them - measure of confidence as well as variability

mark and recapture

capture organisms, mark them, release them back into the environment, and repeat

Lincoln Peterson Index

mark and recapture

number marked in second sample = number marked in first sample

---

total caught in second sample = size of whole population

or: N=M*S/r

quadrat sampling

place quadrat in a randomly determined location in a sampling area and count # of individuals within quadrat and repeat

Population density:

total # organisms in all quadrats

---

total # quadrats * area of quadrat

population size: population density * entire sample area

Line Transect Sampling (3 methods)

Set up a line of a specific length from a particular point

3 methods:

1. count organism touching the line

2. count organisms a specific distance from the line

3. count organisms within quadrats placed at specific intervals along line

3 stages of sigmoid population growth

1. exponential phrase: unimpeded reproduction, resources abundant, nothing limiting growth

2. transitional phase: increasing limiting factors and growth slows

3. plateau phase: population fluctuates around carrying capacity

density-dependent limiting factors

affect population growth only when the population size becomes larger

ex: competition for resources

density-independent limiting factors

affect population growth at any time, no matter how large or small the population is

ex: natural disaster

carrying capacity

max number of individuals in a population that the environment can support

population growth logistic model (change in population size/change in time)

max possible growth rate x current population size x (1-(current population size)/carrying capacity)

intraspecific competition

interaction between individuals within a population that require a resource that is in limited supply → tend to share an ecological niche and resources (Natural Selection aids in this)

intraspecific cooperation

when members of the same species work together to help the group survive

community

a group of populations living together in an area and interacting with each other

interspecific relationships

relationships between different species in a community

herbivory

herbivores (primary consumers) feed on producers (autotrophs)

producers may or may not be killed

predation

consumer/predator kills and eats another consumer species (prey)

prey always killed by predator

interspecific competition

two or more species using the same resource, with the amount taken by one species reducing the amount available for the other species

mutualism

two species living in a close association with both species benefiting

parasitism

one specieis (parasite) living inside or on the surface of another species (host) and obtaining food from them

parasite benefits while host is harmed, not the intention of the parasite

pathogenicity

one species (pathogen) living inside another species (host) and causing a specific disease in the host

pathogen does harm by reproducing within host and host may die

chi-square test for independence

statistical test commonly used to describe significant association between two variables

expected frequency

column total x row total

---

total number of quadrats