the open ocean

Question 1

what zone is considered the open ocean

Answer 1

the pelagic zone

Question 2

how does patchiness vary in the open ocean

Answer 2

• physical properties
• biological production
• biomass

Question 3

what is the hypographic curve

Answer 3

represents seabed topography and is the graphical representation of the depth of a body of water at certain intervals

Question 4

how deep is the Mariana trench

Answer 4

found in the Pacific ocean it is 11,022m deep

Question 5

what are the different pelagic zones

Answer 5

1) epipelagic (sunlit/euphotic) 200m
2) mesopelagic - 1,000m
3) bathypelagic - 4,000 m
4) abyssopelagic - 5000m
5) hadopelagic- 6000m

Question 6

outline characteristics of the epipelagic zone

Answer 6

the surface- 200m deep
warmest
best lit
most life in the ocean is reliant on productivity within this zone

Question 7

what is a thermocline

Answer 7

an abrupt temp gradient in a body of water such as a lake marked by a layer above and below which the water is at different temperatures

Question 8

outline characteristics of the abyssopelagic zone

Answer 8

mean water depth of 3,682m deep
near constant conditions
waters originate at the air-sea interface in polar regions

Question 9

what are the two provinces of the epipelagic zone

Answer 9

1) netric which is near shore
2) oceanic which is beyond the continental shelf

Question 10

what two basic groups of marine organisms is home to pelagic environments

Answer 10

1) plankton meaning wanderer or drifter= unable to swim significant distances so passivley transported in ocean currents
2) nekton meaning free swimmers

Question 11

what techniques are used to sample plankton

Answer 11

• traditional towed nets
• genomics
• underwater photography
• satellites

Question 12

what are the different sizes of plankton

Answer 12

1) femtoplankton = less than 0.2um
2) picoplankton = less than 2 um
3) nanoplankton = less than 20um
4) netplankton= less than 20cm

Question 13

what is meant by the term Holo-planktonic

Answer 13

all life cycle is in the water column

Question 14

what is meant by the term mero-planktonic

Answer 14

only part of the life cycle is in the water column

Question 15

what is a copepod

Answer 15

a type of zooplankton crustacea which dominate the net zooplankton and mostly feed on phytoplankton

Question 16

what is diel vertical migration (DVM)

Answer 16

the largest migration in terms of biomass on the planet in which animals which occur in deeper water during the day move to shallower water during the night

Question 17

what are some issues for organisms staying afloat

Answer 17

• cells and tissues are usually heavier than water
• shells and skeletons are even more heavier

Question 18

what are some solution to organisms staying afloat

Answer 18

• to keep swimming
• increase water resistance= increase SA
• increase buoyancy= store lipids, gas pocjers

Question 19

what is the difference between neuston and pleuston organisms

Answer 19

N= organisms that live at sea surface but remain underwater
P= organisms which part of the body is above the surface

Question 20

what is the microbial loop

Answer 20

describes trophic pathways where in aquatic systems DOM is returned to higher trophic levels via the incorporation into bacterial biomass

Question 21

what controls the abundance of epipelagic organisms

Answer 21

• sunlight
• nutrients
• phosphate
• iron
  -silicon
  they follow the pattern of primary productivity

Question 22

what affects light penetration in the ocean

Answer 22

• seasons
• weather
• turbidity
• self-shading by plankton