Ecosystems, food webs and energy flow

Question 1

Ecosystem

Answer 1

Biological community of living organisms interacting with each other and their physical and chemical environments

Question 2

What % of the earth’s surface do oceans cover?

Answer 2

71%

Question 3

Transfer and exchange of energy and organic matter

Answer 3

Production –> Consumption –> Decomposition

Question 4

What % of nutrients are recycling within the euphotic zone

Answer 4

80-90%

Question 5

Chemosynthesis

Answer 5

Oxidation of inorganic molecules (H2, H2S, CH4 )

Question 6

Bacterial remineralisation

Answer 6

Organic N –> NH3+2O2 (ammonia + oxygen) –> H+ + NO3- +H2O (proton +nitrate+water)

Question 7

Microbial carbon pump

Answer 7

Conversion of DOC to POC by marine microbes e.g. bacteria and phytoplankton

Question 8

Microbial Carbon Pump

Answer 8

Primary production–> Microbial transformation–> Export to depth–> Carbon sequestration

Question 9

3 types of symbiotic relationship

Answer 9

Mutualistic, Commensal, Parasitic

Question 10

Mutualistic

Answer 10

Relationship where both species benefit

Question 11

Commensal

Answer 11

Relationship where one benefits and the other is neutral

Question 12

Parasitic

Answer 12

relationship where one benefits and one is harmed

Question 13

Obligate

Answer 13

Essential for survival

Question 14

Facultative

Answer 14

Not essential

Question 15

Example of obligate mutualistic symbiosis

Answer 15

Clownfish feed on small invertebrates that could harm sea anemone, clownfish faecal matter provide nutrients for anemone- mutual protection from predation

Question 16

Example of commensal symbiosis

Answer 16

Beneficial to filter-feeding barnacles by increasing range and food sources ; no benefits or threats to the whale

Question 17

Parasitic symbiosis

Answer 17

Beneficial to isopod whilst harming fish by eating its tongue and then accessing all food

Question 18

Algal photosynthetic endosymbionts

Answer 18

Live inside the body or cells - very common in marine metazoa and protists

Question 19

Mutualistic example- zooxanthellae

Answer 19

Zooxanthellae provide food through photosynthesis; corals provide habitat and nutrients for zooxanthellae

Question 20

Open ocean - food web energy transfer

Answer 20

Nanoplankton–> Microzooplankton–> macrozooplankton–> megazooplankton–> zooplanktiveorous fish –> pisciveros fish

Question 21

Total primary production Open ocean

Answer 21

81.5%

Question 22

Humankind as top predators

Answer 22

• Fisheries
• Whaling
• Seafloor dredging
• Ensnarement
• Accidental Catch

Question 23

% of ocean covered by marine protected areas

Answer 23

8.16%