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Biology A2 > 3.5 - Population size > Flashcards

3.5 - Population size Flashcards

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1
Q

Birth rate?

A

the reproductive capacity of a population where the number of new individuals is given as reproduction per unit time

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2
Q

Population?

A

An interbreeding group of organisms of the same species occupying a specific habitat

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3
Q

Immigration?

A

the movement of individuals into a population of the same species

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4
Q

Fugitive species?

A

a species that’s poor at competition + reliant on a large capacity for reproduction and dispersal to increase their numbers

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5
Q

Equilibrium species

A

a species that controls their population by competition not reproduction or dispersal

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6
Q

Biotic?

A

a factor which makes up the living part of the environment of an organism such as a pathogen or predator

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7
Q

Abiotic?

A

a non living part of the environment of an organism such as temp or oxygen

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8
Q

Carrying capacity?

A

the maximum number around which a population fluctuates in a given environment

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9
Q

Environmental resistance?

A

environmental factors that slow down population growth

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10
Q

Population growth curve

A

x axis - time
( mins/hr/month/years)
y axis - number of organisms

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11
Q

places on growth curve

A

1) lag phase
exponential phase
stationary phase
death phase

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12
Q

lag phase?

A

a period of slow growth
period of adaptation + preparation
intense metabolic activity
enzyme synthesis
Organisms such as mammals - lag phase = time taken to reach sexual maturity

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13
Q

Exponential phase?
real steep

A

population doubles per unit time
no factor limiting the growth of the population
the rate of increase is not sustainable due to environmental resistance

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14
Q

things that could cause it to drop

A

predation
less food available
concentration of waste
nesting sites
competition
overcrowding
disease

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15
Q

difference between
abiotic and biotic ?

A

biotic = living
abiotic = dead

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16
Q

stationary phase?

A

birth rate is = to the death rate
population has reached its maximum size
(carrying capacity)
populations are not constant but fluctuate around the carrying capacity

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17
Q

death phase?

A

death rate is greater than the birth rate
the graph has a negative gradient

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18
Q

factors that regulate population increase?

A

density dependent factors
their effect increases as the density of the population decreases
e.g accumulation of waste
disease
paratisim
depletion of food

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19
Q

density independent factors?

A

e.g earthquakes
flooding
fire
bacteria
temp

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20
Q

abundance?

A

the number of individuals of a species in a given area or volume

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21
Q

measuring abundance?

A

lincoln index calculation

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22
Q

technique for land?

A

capture, mark, recapture
example
collect some snails, mark them with nail vanish or something and release them. then in 2 weeks or so collect them again . working out the ratio in an area

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23
Q

technique for aqautic?

A

kick sampling
used in a stream for aquatic vertebrates

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24
Q

measuring the abundance of plant species?

A

use a quadrat to calculate the mean number of individuals
can also estimate the percentage cover of a plant
can also estimate the percentage frequency

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25
what is the distribution?
the area or volume in which organisms of a species are found - measured with a transect
26
transect? (line)
a line from one habitat to another along which quadrats can be placed to work out the distribution of a species e.g (forest coming out of a forest)
27
transect? (belt)
shows the abundance through a given area at distances along a transect possible to work out the density of the species or the percentage area of the species presented as a kite diagram
28
when is a transect suitable?
if the plants and animals are sessile (dont move a lo)
29
Habitat?
place in which an organism lives
30
Ecosystem?
characteristic community of interpendent species interacting with the abiotic components of their habitat
31
community?
Interacting population of 2 or more species in the same habitat at the same time
32
Trophic level?
number of times that energy has been transferred between the sun and successive organisms along a chain
33
Biomass?
mass of biological material in living or recently living organisms
33
Saphrobiont?
microorgnaim that obtains its food from dead or decaying remains
33
Gross primary productivity?
rate of production of chemical energy in organic molecules by photosynthesis in a given area in a given time measured in kJ m-2 y-1
34
Net primary Productivity?
energy in the plants biomass which is available to primary consumers measured in kJm-2y-2
35
primary productivity?
Rate at which energy is converted into biomass
36
Secondary Productivity?
rate at which consumers convert chemical energy of their food into biomass
37
succession?
the change in structure and species composition of a community overtime
38
climax community?
a stable self perpetuating that has reached equilibrium with its environment and no further change occurs
39
Pioneer species?
the first species to colonise a new area in an ecological succession (algae, lichen and mosses)
40
41
Secondary succession?
the changes in a community, following the disturbance or damage to a colonised habitat
42
Niche?
the role and position a species has in its environment including all interactions with biotic and abiotic factors
43
Mutualism?
an interaction between organisms of 2 species where both dervive benefit
44
Commensalism?
interaction between organisms of 2 species where 1 both benefits and the other is not affected
45
Global warming?
Increase of average Global temp in excess of the greenhouse effect caused by the atmosphere's historical concentration of CO2
46
Carbon footprint?
the equivalent volume of CO2 generated by an individual, a product or a service in 1 year
47
Types of ecosystem?
can be small such as the human intestine or large such as the pacific ocean they can be temporary such as a puddle or permanent such as the artic tundra
48
Examples of Ecosystems?
Marine e.g the pacific ocean abiotic factors = aquatic with a high mineral concentration Algae Echinoderms (starfish) Sardines Herrings Swordfish
49
Example 2?
Artic tundra Its in Canada and Siberia Abiotic factors = the temp which are between - 50 and + 12 15 -25 cm of rainfall per year windy Organisms in the Artic Tundra Artic Hare Artic Fox Reindeer Plants in the Artic Tundra Heather
50
Eco System 3?
Temperate Deciduous forest (leaves fall off) Lady park wood in Monmouthshire Conditions moist and warm Organisms Beech and Oak tree Woodpecker Owl
51
Eco system 4?
Desert e.g Sahara which spans 11 countries in North and Central Africa Abiotic features Less than 25m rainfall a year High temp - between 30 and 50 degrees High light intensity Animals Lizards Cacti Camels
52
Food chains? Examples of producers
green plants Cycano bacteria and Protoctista because they turn the suns energy into carbohydrates
53
Primary consumer?
herbivore and only feed on plants
54
Secondary consumer?
Carnivores or omnivores
55
Trophic level?
energy passes between feeding levels and is lost as heat or faeces
56
Decomposition?
Detrivores eats detritus which are the remains of dead organisms of fallen leaves examples earthworms, woodlice and millipedes
57
Decomposers?
obtain nutrients from dead organisms and animal waste examples - bacteria and fungi
58
What is the equation for photosynthetic efficiency ?
the energy flowing from one organism to another originates as sunlight
59
why is 60 % of light energy that falls on a plant is not absorbed by photosynthetic pigments ?
wrong wavelength reflected or transmitted straight through the leaf
60
Equation
PE = quantity of light energy in the products / the quantity of energy falling on the plant x 100
61
Efficiency
why old plants have a PE of 1 % cropped plants have a PE of 8 %
62
What is efficiency dependent on?
the plant genotype and environmental factors (light intensity + temp)
63
What is gross Primary productivity?
the rate of production of chemical energy in organic molecules by photosynthesis
64
Net primary productivity?
the energy in a plant's biomass
65
What is the equation for it?
NPP = GPP - Respiration
66
What does Ecological pyrimads do?
shows each trophic level in an ecosystem pyrimads of number can be inverted but biomass and energy cannot
67
Succession def?
change in the community structure and species over time can take decades for succession
68
Example of a climax community has reached equilibria
mature woodland
69
Where does primary succession occurs?
on bare rock or at the site of volcanic eruption soil is fertile
70
Sere?
a sequence of communities
71
What is XeroSere?
a community in a dry environment
72
Seral stages?
changes in the environment that make it suitable for specific species
73
What are Pioneer species?
the first organisms to colonise bare rock e.g algae lichen moss
74
Weathering of rock by lichen and accumulation of dead decaying matter forms what?
primitive soil
75
As the soil develops in nutrients what grows?
grass + small plants compete with moss
76
Animals such as ants, spiders and mites ?
can survive
77
What does tall grass provide?
shade and the community becomes more complex
78
What happens when plants die + decay
soil becomes thicker and is able to hold water for trees to decay
79
Habitat?
place in which an organism lives
79
Biomass?
mass of biological material in living or recently living organisms
79
Ecosystem?
characteristic communtiy of interdependent species interacting with the abiotic components of their habitats
79
Community?
Interacting population of 2 or more species in the same habitat at the same time
79
Trophic level?
number of times that energy has been transferred between the sun and successive organisms along a chain
79
Net primary productivity?
energy in plants biomass which is available to primary consumers measured in KJm-2y-1 years
79
Saphrobiont?
microorganism that obtains its food from dead or decaying remains
79
Gas primary productivity?
rate of production of chemical energy in organic molecules by photosynthesis in a given area in a given time measured in KJ m-2 y-2
79
Secondary productivity?
rate at which consumers convert their chemical energy of their food into biomass
79
Primary productvity?
rate at which energy is converted by producers into biomass
80

Biology A2 (9 decks)

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