Nutrient Cycle

Question 1

Aboiotic

Answer 1

the environment’s geological, physical and chemical features, the non living part of an ecosystem

Question 2

Assimilated

Answer 2

the conversion of a nutrient into a usable form that can be incorporated into the tissues of an organism

Question 3

The living part of an ecosystem, which includes the organisms and their effects on each other

Answer 3

Biotic

Question 4

Decomposers

Answer 4

bacteria and fungi that break down dead organic matter and release the nutrients back into the environment

Question 5

Nutrient

Answer 5

a chemical that provides what is needed for organisms to live and grow

Question 6

Nutrient cycle

Answer 6

the movement and exchange of elements that are essential to life, from inorganic molecules, through fixation and then into living organisms before being decomposed back into inorganic molecules

Question 7

Reservoir

Answer 7

part of the abiotic phase of the nutrient cycle where nutrients can remain for long periods of time

Question 8

The flow of water from land caused by precipitation

Answer 8

Run-off

Question 9

Upwelling

Answer 9

The movement of cold, nutrient-rich water from deep in the ocean to the surface

Question 10

The average time that a particle spends in a particular system

Answer 10

Residence time

Question 11

Algae/phytoplankton require light for

Answer 11

photosynthesis and other ions for growth

Question 12

All nutrient cycles have a

Answer 12

biotic and abiotic phase

Question 13

A nutrient moves from abiotic to the biotic phase when it is

Answer 13

absorbed and assimilated by producers

Question 14

Nutrients are lost by

Answer 14

egestion and excretion

Question 15

After death, organisms are broken down by

Answer 15

decomposers which allow the nutrients to return into their inorganic form

Question 16

Generalized cycle

Answer 16

Nutrients found as inorganic ions and compounds in the atmosphere, dissolved in water, forming rocks and sediment

Question 17

All nutrients have this general cycle:

Answer 17

-Atmosphere and land
(dissolving and runoff)
-Reservoir of dissolved nutrients in the surface layer of sea 
(uptake)
-food chains ---> (harversing)
(sinking and incorporation into reefs)
-sea bead
(upwelling)
-back to reservoir of dissolved nutrients in the surface layer of sea

Question 18

Sulphate

Answer 18

To make amino acids

Question 19

To make chlorophyll

Answer 19

Magnesium

Question 20

Calcium

Answer 20

to make bones, coral, and shells

Question 21

To make amino acids/ protein, and DNA/RNA

Answer 21

Nitrate

Question 22

Phosphate

Answer 22

To make DNA, ATP, bones

Question 23

Average residence times for nutrient ions in the ocean are

Answer 23

very long because some of them fall to the bottom in faeces or dead organisms

Question 24

Nutrients spend less time on the surface layer of the ocean because

Answer 24

they are constantly being used and recycled by organisms living there

Question 25

Infiltration

Answer 25

part of the water cycle where water soaks into the soil from ground level and mover underground

Question 26

Leaching

Answer 26

a process during which water-soluble nutrients are removed from the soil and dissolve in water that is flowing to the sea (run off)

Question 27

Causes of run off:

Answer 27

• deep currents being deflected upwards by coastline

- wind moving the surface water away from the shore creating circulation

Question 28

Example of gas in the atmosphere being dissolved into the ocean surface

Answer 28

carbon dioxide dissolving in seawater forming hydrogencarbonate ions making more CO2 for photosynthesis

Question 29

Amount of gas that can dissolve in the water depends on the:

Answer 29

• temperature of the water
• atmospheric concentration of each gas
• amount of mixing of water at the surface

Question 30

Sink

Answer 30

an area where there will be more gas dissolving in the water than there is diffusing back into the atmosphere

Question 31

Source

Answer 31

an area where more gas will diffuse into he atmosphere than dissolving into the water

Question 32

Nutrients are lost from the surface reservoir when they are incorporated into primary producers and used…

Answer 32

to make organic compounds which move up the food chain during feeding

Question 33

Reservoir in the surface layer can decrease when…

Answer 33

organisms die and sink to the ocean floor that trap nutrients in them

Question 34

The act of decomposing

Answer 34

Detritus

Question 35

Harvesting

Answer 35

When fish or other organisms are removed by humans from the sea and the nutrients are lost from the ecosystem