B9 - Ecosystems And Human

Question 1

What is parasitism

Answer 1

Relationships between species, where a parasite lives on or in another organism, causing harm

Question 2

What is mutualism

Answer 2

A relationship that is beneficial to both organism

Question 3

What is a decomposer

Answer 3

Organisms that break down dead or decaying organisms

Question 4

What is Biodiversity

Answer 4

The variety of plant and animal life

Question 5

What is conservation

Answer 5

Management of the environment and its natural resources

Question 6

What is reforestation

Answer 6

Replanting trees that have been lost

Question 7

What is Food security

Answer 7

The ability to produce enough food for the population

Question 8

Biotic Factor

Answer 8

Living component

Question 9

Abiotic Factor

Answer 9

Non-living factors that affect an ecosystem

Question 10

Factors that affect food security

Answer 10

Increasing population
Increasing meat and dairy consumption
New pests or pathogens
Environmental challenges
Biofuels

Question 11

Carbon cycle processes

Answer 11

Respiration, Photosynthesis, Decomposition, Combustion.

Question 12

Nitrogen cycle

Answer 12

A process in which nitrogen moves from the atmosphere through living and dad organisms, into the soil and back to the atmosphere
Nitrogen fixing Bacteria
Nitrifying
Denitrifying
Decomposers

Question 13

What is crop rotation

Answer 13

a different t crop is planted in the field in a 3/4 year cycle
This controls nitrate levels in the soils

Question 14

What is manure, and its use

Answer 14

Mixture containing animal waste (and urea)
Added to soil, so it can be broken down by decomposers into ammonia, the ammonia is then broken down by Nitrifying bacteria, into nitrites, then nitrates

Question 15

What is a nitrate

Answer 15

A compound that contains nitrogen in the form of a nitrate ion

Question 16

What is nitrogen used to make

Answer 16

Amino acids —> proteins

Question 17

Why can nitrogen itself not be used by plants

Answer 17

It is inert, so need the nitrogen to be converted to nitrates first

Question 18

Why are proteins essential

Answer 18

For growth and repair, enzymes and hormones

Question 19

What do Nitrogen fixing bacteria do

Answer 19

Convert nitrogen (N2) onto nitrates (NO3)
found free living in the soil, and in root nodules of roots of plants

Question 20

What do nitrifying bacteria do

Answer 20

Ammonia (NH3) into nitrites (NO2) into nitrates (NO3)

Question 21

What removes carbon from the atmosphere

Answer 21

Photosynthesis by plants

Question 22

In photosynthesis, carbon starts as CO2, what does it end up as

Answer 22

Carbon dioxide + water —> Oxygen + Glucose

Question 23

What process returns carbon to the atmosphere

Answer 23

Respiration and Combustion

Question 24

During respiration, carbon stars as glucose, what does it end as

Answer 24

Oxygen + glucose —> Carbon dioxide
Glucose —> Carbon dioxide

Question 25

How does carbon pass through the ecosystem

Answer 25

Via the food web

Question 26

How does water enter the atmosphere

Answer 26

Evaporation from water bodies
Transpiration out of plants

Question 27

How does water in atmosphere return

Answer 27

water vapour condenses, the comes back down to the ground via precipitation

Question 28

What does potable mean

Answer 28

Clean drinking water

Question 29

What is Desalination

Answer 29

Removal of excess mineral ions from water, to make it potable

Question 30

What is Distillation

Answer 30

Saline water is boiled, the water vapour then travels through a tube, where it it is cooled and therefore condenses, and the pure water is then collected

Question 31

What is reverse osmosis

Answer 31

Stalin water is forced through a partially permeable membrane, which filters out all the mineral ions, leaving only pure potable water

Question 32

What are the disadvantages of distillation

Answer 32

Expensive - due to energy needed
Carbon dioxide released due to energy being produced

Question 33

5 ways biodiversity can be protected

Answer 33

Controlled breeding
Protection of endangered areas
Replanting hedgerows
Reduce deforestation so there is more O2
Recycle waste, to protect land

Question 34

What is Eutrophication

Answer 34

Fields are fertilised, rain washes it into rivers
High nitrate and phosphate levels in the water, cause rapid algae growth
The algae block sunlight, so plants in the water die due to lack of sunlight
Therefore there is no kore oxygen being produced
Decomposers and bacteria grow rapidly due to the dead plant matter
These bacteria, along with existing marine life, use up the oxygen supply
Therefore dying off quickly

Question 35

What is Fish farming
Advantages and Disadvantages

Answer 35

Keeping fish in captivity to breed and farm

Fast and Profitable

Diseases and parasites spread quickly

Question 36

What is affected by the introduction of species

Answer 36

Native species that are in the area

Question 37

Why are species introduced to ecosystems

Answer 37

For farming, or to rebalance an ecosystem via predation or competition

Question 38

What is Competition

Answer 38

Organisms both need the same resource, one is better adapted to gathering

Question 39

What is Predation

Answer 39

One animal species kills and eats another animal species

Question 40

What is the predator-prey cycle

Answer 40

Te regular variation of numbers between prey and the predators in a feeding relationship

Question 41

Formula to estimate population size

Answer 41

Peterson Capture recapture

Total organisms in sampled area x (total area/quadrat area)