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Biology Unit 3 > Population Size & Ecosystems > Flashcards

Population Size & Ecosystems Flashcards

(71 cards)

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1
Q

Factors affecting population size

  • b… rate - no. Of individuals sexually or asexually … per unit time - … the pop
  • d… rate - no of individuals … per unit time - … the pop
  • i… - … individuals joining a pop - … the pop
  • e… - indivuals … a pop - … a pop
A

Birth - reproduced, increases
Death - dying - decreases
Immigration - new, increases
Emigration - leaving, decreases

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2
Q

Population growth equation

(B… + I…) - (D… +E…)

A

Birth
Immigration
Death
Emigration

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3
Q

Strats for pop growth

  • f… species - rapidly reproduce alongside dispersal mechanisms means they can invade fast
  • e… species - control pop by competition
A

Fugitive
Equilibrium

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4
Q

One step growth curve

Lag
Exponential
Stationary
Death

A
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5
Q

Lag phase

Organism … to their environments

Bacteria - … activation

A

Adjusts
Gene

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6
Q

Exponential phase

Organisms …
Minimal limiting …
Therefore, pop grows at an … rate

Bacteria - cell …

A

Reproduce
Factors
Increasing

Divide

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7
Q

Death phase

… rate exceeds … rate
Resources are …

Bacteria - cells … exceeds those produced by …

A

Death
Birth
Depleted

Dying
Division

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8
Q

Intraspecific competition

Competition for limited … between members of the … species

A

Resources
Same

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9
Q

Stationary phase

Levels off as … rate = … rate
Factors become …

Bacteria -cell dying = those produced by …

A

Birth = death
Limiting

Division

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10
Q

Interspecific Competition

Compeition for resources between organisms of … species

A

Different

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11
Q

Predator-prey interactions

No. Of prey - limits … pop growth - less food, less mouths fed

No. Of predators - limits … pop growth - more preds, more prey eaten

Interaction …

A

Predator
Prey

Oscillates

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12
Q

Carrying capacity

= maximum … size that can be …

Corresponds to the … phase

A

Pop
Sustained

Stationary

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13
Q

How might carrying capacity increase?

  • increase in … availability
  • create new …
A

Food
Habitat

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14
Q

Density dependant factors

BIOTIC
E.g. c…, p…, d…, p…
The effect on pop depends on … of pop

Determines c… c… as it limits max pop

A

Competition
Predation
Disease
Parasitism

Size

Carrying capacity

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15
Q

Density independent factors

ABIOTIC
E.g. t…, p…, natural …

The effect on pop depends is the same regardless of pop size

A

Temp
pH
Disasters

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16
Q

Abundance

= no. Of individuals of the … species in a given area

A

Same

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17
Q

Niche

An organism’s … within an ecosystems

Organisms cannot occupy the same niche due to … for resources

A

Role
Competition

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18
Q

Ecosystems

= community of interdependent …, comprised of … & … elements and is subject to … (dynamic)

A

Species
Biotic
Abiotic
Change

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19
Q

Producers

Convert simple … compounds into complex … compounds like carbs

Autotrophic organisms (e.g. plants)

A

Inorganic
Organic

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20
Q

Consumers

Cannot fix … from inorganic sources
…/… carbon from other organisms

Heterotrophic

A

Carbon
Ingest/absorb

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21
Q

Decomposers
E.g. bacteria & fungi

break down … compounds (e.g. dead/decaying matter) into … compounds (soluble & get absorbed by plants)

A

Organic
Inorganic

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22
Q

Energy lost that is never even absorbed (sunlight)

  • light is … from leafs surface
  • incompatibility between … of light & photosynthetic …
A

Reflected
Wavelengths
Pigments

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23
Q

Energy lost as it passes from one trophic level to the next

  • as … in …
  • … of waste
  • not all parts are …
A

Heat
Respiration
Egestion
Eaten

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24
Q

Gross Primary Productivity

Rate of conversion of … energy into … energy by …

A

Light
Chemical
Photosynthesis

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25
Net primary productivity Energy in plant … that is available to … consumers GPP - energy lost in plant …
Biomass Primary Respiration
26
Increase in temp effect on NPP in plants NPP … More … is used for … than produced by …
Decreases Carb Respiration Photosynthesis
27
Primary productivity Rate energy is converted by … into biomass
Producers
28
Secondary productivity Rate … convert chemical energy of their food into biomass (e.g. new…/…)
Consumers Cells/tissues
29
Biomass = mass of biological … Closely related to energy as the molecules that make up tissues, contain energy Difficult to measure - e.g. … may be hard to harvest Not all available to next trophic level - e.g. … - contain energy but not transferred
Tissue Roots Bones
30
Pyramids of energy Show quantities of energy … from one trophic level to the next
Transferred
31
Succession = Change in … & composition of … in a … overtime, due to … factors (abiotic)
Structure Species Community Environmental
32
Primary succession Environment has not been previously … by … species Bare …
Colonised Pioneer Rock
33
Secondary succession Environment has been previously colonised Bare …
Soil
34
Stages of succession = …
Seres
35
Climax Community = stable, … community with high … where no further changes occur
Self-perpetuating Biodiversity
36
Name given to group of organisms that inhabit an ecosystem at the end of a successional change … community
Climax
37
What usually happens to species diversity as succession proceeds> …
Increases
38
Human activity prevent a climax community being reached - … sheep -… of land - … - soil …
Grazing Farming Deforestation Erosion
39
Why is a climax community reached quicker during secondary succession? … is already present May contain bulbs, seeds, spores
Soil
40
First organisms to colonise bare rock …
Pioneer
41
Recolonisation by living organisms … succession
Secondary
42
Importance of carbon Key component of many biological molecules E.g. proteins, carbs, lipids, nucleic acids
43
Carbon cycle 1) … from atmosphere is … into carb by light … stage of photosynthesis 2) … releases CO2 due to … 3) … of fossil fuels releases CO2 into … 4) … feed on dead/decaying matter & release CO2 during … 5) carbon within organic molecules pass up … levels -along food … 6) fossil fuels form from remains of dead matter, over million of years - … condition inhibits decay
CO2 Fixed Independent Respiration Decarboxylase Combustion Atmosphere Decomposers Respiration Trophic Chains Anaerobic
44
Humans disrupting carbon cycle - … (less … so less carbon …) - burning … … (more CO2 releases due to …)
Deforestation Photosynthesis Fixation Fossil fuels form Combustion
45
Greenhouse gas’s effect Atmospheric … level causing global warming Climate change: - melting polar ice caps & rising sea levels - more frequent extreme weather - increased extinction rate
CO2
46
Carbon footprint = total amount of … produced direclty due to … activity Agriculture: - production of t… - production of i… - … - powered by … - transport of …
CO2 Human Tools Insecticides Machinery - fossil fuels Produce
47
Reducing carbon footprint - produce less … - required more resources than … - crops grown for … consumption not animal feed - minimum …
Meat Crops Human Packaging
48
Importance of nitrogen Component of nucleotides (e.g. ATP, DNA & RNA) And found in chlorophyll
49
Nitrogen cycle = flow of … & … itrgen within the … & … elements of an … Plant roots absorb nitrogen as … or… by …transport against a conc. gradient. Nitrogen gets incorporated into the plants biological molecules, then passed along food …
Organic Inorganic Biotic Abiotic Ecosystem Nitrate/ammonium Active Chains
50
Nitrogen fixing = fixing … nitrogen gas into … ions
Atmospheric Ammonium
51
Nitrogen fixing bacteria 1) a… - fixes nitrogen gas into … ions - a… 2) r… (found in root nodules of …) - uses … enzymes to fix nitrogen gas into … ions - a… - … relationships
Azotobacter Ammonium Aerobic Rhizobium Legumes Nitrogenase Ammonium Anaerobic Mutualistic
52
Leghaemoglobin Surrounds … Combines with … and prevents it reaching the … bacteria
Rhizobium Oxygen Anaerobic
53
Form of nitrogen produced by rhizobium …
Ammonium
54
Where is rhizobium found in a legume? … …
Root nodules
55
Mutualism Both organisms derive …
Benefit
56
Mutualised relationship between nitrogen fixing bacteria & plants Bacteria pass… contain compounds to the plant … from plant pass to bacteria
Nitrogen Carb
57
Nitrification = converting products of … (ammonium ions) into … ions E,g, organism dies, bacteria & fignhi release nitrogen during decay, products of decomposition are … ions
Decay Nitrate Ammonium
58
Explain the process of bacteria carrying out Nitrification and why it is important for soil fertility Bacteria = nitrosomonas & nitrobacter Nitrosomonas convert … into … Nitrobacter convert … to … which plants can … from the soil And use for … acid, … synthesis etc.
Ammonia Nitrite Nitrite Nitrate Absorb Nucleic Protein
59
Denitrification = loss of soluble … compounds from the soil Under anaerobic conditions, nitrate is converted into … nitrogen and lost from the … Decreases soil fertility - bad for farmers
Nitrate Atmospheric Soil
60
Nitrogen cycle A) D… - …break down organic molecules in plant remains into inorganic … B) N… - … convert ammonia into nitrite, … convert nitrite to nitrate C) D… - … process, inorganic … sources are converted into nitrogen gas by … D) Nitrogen … - bacteria fixes … nitrogen into …/… E) Absorption - nitrogen absorbed by the root … cells by … transport, … a conc. gradient
Decay Decomposers Ammonium Nitrification Nitrosomonas Nitrobacter Densification Anaerobic Nitrogen Pseudomonas Fixation Atmospheric Ammonium/nitrate Hair Active Against
61
Nitrogen cycle - positive Hyman activity Improve availability of soluble … - adding … (ammonium nitrate) - adding … (animal waste) - ploughing/draining
Nitrate Fertilisers Manure
62
Nitrogen cycle - negative human activity reduces biodiversity: - excess … - increase growth of weeds - more competition - draining destroys … - nitrate pollution causes … -less dissolved …
Nitrates Habitats Eutrophication - oxygen
63
Eutrophication Fertilisers, manure, slurry etc. wash into water if in excess increase soluble … of the water - increase … growth - may cover … of water, blocking … to reach plants at lower depths, plant dies - cannot … - aerobic bacteria feed on (decompose) dead plants.algae - they …, less … in water so organisms die due to … - water becomes … - … bacteria grow, fall in … levels
Nitrate Algal Surface Light Photosynthesise Respire Oxygen Suffocation Anaerobic Denitrifying Nitrate
64
Consumption efficiency (net production) of herbivores is lower than carnivores Herbivores: have more … material in diet (e.g. …) Carnivores: more effecient at digesting … & … Therefore, there is more … material (faeces) lost by eating …
Indigestible Cellulose Protein Fats Egested Plants
65
Why do marine ecosystems have more trophic levels than terrestrial - higher … productivity - high … productivity - less … used due to …
Primary Secondary Energy Buoyancy
66
Competition between 2 species, one gets infected with a parasite The other species population …; There is less … for food etc.
Increases Competition
67
Why does eutrophication cause death? Increase … growth Less … so plants die Bacteria … plant material Using up … in … (aerobic bacteria)
Algal Light Decompose Oxygen, respiration
68
Crops farmers use to increase nitrate levels … plants; … (nitrogen fixing bacteria) in the … …; Convert … gas into …
Leguminas Rhizobium Root nodules Nitrogen Ammonia
69
Explain why keeping cattle on land is less efficient than growing crops Energy is … as it passes to the next … level During respiration, movement, excretory products, not all parts eaten etc.
Lost Trophic
70
Negative impact on earths atmosphere of Kevin large numbers of cattle Cattle produce … in respiration & Take up space for plants - …, less CO2 absorbed in … Contributes to the … effect
CO2 Deforestation Photosynthesis Greenhouse gas
71
Suggest why growing crops used to produce biofuel is carbon neutral Burning biofuels increases … in air But, … removes CO2
CO2 Photosynthesis

Biology Unit 3 (8 decks)

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