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Flashcards in ecology Deck (20):
1

what are the factors that can affect the size of a population

births deaths immigration and emigration

2

what are the methods to find the population size

counting all individuals
plot sampling
mark and recapture

3

how do you plot sample

divide area into smaller plots
count # of individuals in each plot
average it
then use proportion
#average per plot \ area of plot =x\total

4

how do you mark and recapture

capture animals
Mark them
put them back into environment
recapture # of animals then use proportion

#marked in recapture/total recaptured =#marked the 1st time \x

5

what is population density

the number of individuals of a species per surface area or volume of water

6

what's the equation for population density

# individuals
------------------
surface or volume occupied

7

what does it mean if a population is clumped

most common type of distribution, individuals are in groups that improves their chance of survival

8

explain random distribution

it occurs when there are the same conditions over a territory and little consistency of spacing between individuals

9

what is uniform distribution

individuals maintain an equal distance between each other; this indicates strong competition for space and resources

10

what are the stages of life

birth death and reproduction

11

what are important characteristics of biological cycles,

frequency of reproduction
age of sexual maturity
and number of offspring

12

the larger the organism the ------ the number of offspring

fewer

13

what are biotic factors

living factors that impact the population

14

abiotic factors are

non living ecological factors of physical or chemical nature that can affect a population

15

study population growth

ok

16

what is a carrying capacity

the maximum number of individuals that can be supported in an area since resources are limited

17

what are limiting factors

they are factors that limit the size and growth of a population like competition disease predators parasites

18

how is biodiversity measured

by species richness (total #of species in community) and relative abundance (# of each species in relation to the total organisms)

19

competition
predation
mutualism
and commensalism

what are these relationships

competition -/-
predation +/-
mutualism +/+
commensalism +/0

20

how can a population be characterized by

size, density, distribution and growth over time