Population Ecology

Question 1

population

Answer 1

a group of organisms of a specific species that live in the same area and are able to breed freely with each other

Question 2

ecology

Answer 2

the study of an ecosystem where organisms interact with each other and their environment

Question 3

population ecology

Answer 3

looking at a population and the factors that affect its size

Question 4

species

Answer 4

a group of organisms that are similar and are able to reproduce under natural conditions to produce fertile offspring

Question 5

population parameters

Answer 5

natality, mortality, emigration and immigration

Question 6

increasing population

Answer 6

natality and immigration

Question 7

decreasing population

Answer 7

mortality and emigration

Question 8

migration

Answer 8

the temporary, seasonal movements following the food and water resources

Question 9

closed population

Answer 9

no immigration or emigration, only mortality and natality will affect population size

Question 10

fecundity

Answer 10

number of births per thousand per year

Question 11

direct methods for determining population size

Answer 11

census - counting every individual but the must be large and within a reasonable area

Question 12

indirect methods for determining population size

Answer 12

mark-recapture or quadrant method

Question 13

precautions for determining population size

Answer 13

no hurting of animals, must not affect movement or behaviour, mark cant make the animal more visible to its preditor

Question 14

carrying capacity

Answer 14

the maximum number of one species that the environment can sustain

Question 15

types of population growth

Answer 15

exponential and logistical

Question 16

stable population

Answer 16

fluctuates around the carrying capacity

Question 17

unstable population

Answer 17

the population exceeds the carrying capacity which makes the habitat deteriorate rapidly

Question 18

factors that affect population size

Answer 18

density-dependent or density-independent factors

Question 19

density-dependent factors

Answer 19

limit population growth as a result of the population density. eg. competition for food, disease or parasites

Question 20

density-independent factors

Answer 20

changes in rainfall, temperature, humidity or catastrophic events

Question 21

predation

Answer 21

the biological interaction where one species, the predator, kills and eats another species, the prey

Question 22

how do predators help create and maintain greater diversity within an ecosystem?

Answer 22

by regulating the abundance and distribution of the prey species and keeping the prey population genetically fit

Question 23

aphid-ladybird

Answer 23

female ladybirds lay eggs amongst aphid colonies. the adults then feed on the aphids

Question 24

lion-zebra

Answer 24

depend on each other for survival. adaptation is the speed of movement

Question 25

shark-fish

Answer 25

shark keep fish populations healthy

Question 26

keystone species

Answer 26

a species that has. disproportionally large effect on its environment relative to its abundance

Question 27

competition

Answer 27

when two or more individuals compete for the same resources that are in short supply

Question 28

two types of competition

Answer 28

intraspecific and interspecific

Question 29

intraspecific competiton

Answer 29

between individuals of the same species competing for resources or mates. is the most intense form of competition

Question 30

interspecific competition

Answer 30

between individuals of different species where the conditions necessary to survive and reproduce are similar

Question 31

two types of interspecific competition

Answer 31

competitive exclusion or competitive coexistence

Question 32

competitive exclusion

Answer 32

when one of the two competing species is more successful. can result in extinction and out competition

Question 33

competitive coexistence

Answer 33

when two species coexist because they use the resources differently which is resource partitioning

Question 34

resource partitioning

Answer 34

a process where species with similar requirements living in the same habitat have traits that allow them to use their resources differently.

Question 35

how are resources partitioned

Answer 35

different time, different parts of habitat, different parts of the same plant

Question 36

giraffe and kudu

Answer 36

giraffe eat top, kudu eat tree shoots

Question 37

shorebirds

Answer 37

pickers and probers - probe underground, feed off the shoreline, prey on creatures living in deeper water

Question 38

Lions and leopards

Answer 38

hunt at different times hunt different prey, hunt in different areas of the same habitat

Question 39

how humans intervene to control community structure

Answer 39

by culling which is the reduction of a wild animal population by selective slaughter