Population

Question 1

population definition

Answer 1

a group of organisms which occupy the same environment and are of the same species

Question 2

birth rate

Answer 2

the reproductive capacity of a population and the rate at which reproduction or cell division occurs

Question 3

immigration

Answer 3

the movement of organisms for one population to another

Question 4

equilibrium species

Answer 4

a species which relies on competition and predation for survival

Question 5

fugitive species

Answer 5

species which relies on high reproduction rates and dispersal for survival

Question 6

biotic factors

Answer 6

competition
predation
human activity 
pathogen 
nutrition

Question 7

abiotic factors

Answer 7

sunlight 
water
oxygen and co2
minerals
temperature 
ph
salinity

Question 8

density dependent factors

Answer 8

factors which decrease and become more significant for survival as population increases

Question 9

density independent factors

Answer 9

factors which influence on population size remains constant and never changes despite population growth or decline

Question 10

environmental resistance

Answer 10

abiotic factors that reduce population growth

Question 11

carrying capacity

Answer 11

the maximum population size which an environment can maintain, and fluctuate about

Question 12

negative feedback at carrying capacity

Answer 12

the mechanism by which carrying capacity of an environment is maintained
when population exceeds carrying capacity, factors scarcity and increased competition reduce it back
when population falls below carrying capacity, factors are in abundance and competition is reduced so increases it

Question 13

equation to measure population growht

Answer 13

(birth rate plus migration)-(death rate plus emigration)

Question 14

factors regulating population size

Answer 14

density in/dependent factors

competition

Question 15

population growth curve phases

Answer 15

lag
exponential
stationary
death

Question 16

lag phase example in bacteria and organism

Answer 16

population growth is very slow

organisms are becoming sexually mature
finding mating partner
adaptation phase to the environment
gestation of young

high rates of metabolic activity
protein synthesis, dna replication, respiration to make atp for mitosis

Question 17

exponential phase example in bacteria and organism

Answer 17

rapid population growth 
birth rate exceeds death rate 
no environmental resistance 
resources are in abundance / no density dependent factors restriction 
no overcrowding 
competition isn't limiting

Question 18

stationary phase example in bacteria and organism

Answer 18

carrying capacity is met
birth rate = death rate
negative feedback operates to maintain carrying capacity
environmental resistance increases
density dependent factors become more significant
intraspecific competition increases as organisms of same species require same resources as they have same needs

Question 19

death phase example in bacteria and organism

Answer 19

death rate exceeds birth rate
density dependent factors most significant 
environmental resistance 
build up of waste products 
overcrowding

Question 20

population explosion

Answer 20

rapid rise in population due to alleviation of a limiting factor EG predators
maintained by negative feedback to reduce it

Question 21

measuring abundance methods

measuring distribution methods

Answer 21

ABUNDANCE
quadrat;
mark out a transect line
measure abundance at regular intervals
-% cover (estimate)
-% frequency (mark out tape squares and count how many squares are covered)
-mean area covered
random number generator used to pick coordinate of the quadrat square used
count organisms present in the square
repeat and calculate a mean

capture mark recapture
kick sampling

DISTRIBUTION
belt transect across irregular environment
line transect
repeat abundance measurements using quadrat at regular intervals, focusing on the number of organisms per species/in total as opposed to which species are present

kick sampling in a river

Question 22

capture mark recapture method

Answer 22

place quadrat in sample space
count organisms and mark them with substance that doesn’t affect survival nor kill them
release into environment
redo after a set time period and count how many have the marking

Question 23

belt transect

Answer 23

mark transect line across irregular environment
at regular intervals place down the quadrat
count how many organisms are present

Question 24

abundance

Answer 24

the number of organisms per unit area

Question 25

distribution

Answer 25

the number of organisms that are found in a given area

Question 26

drawback of kite diagram

Answer 26

don’t consider migration

values are rounded so accuracy is lost