Oceanic Biology and Chemistry

Question 1

What are Plankton?

Answer 1

Organisms that are unable to control their position against the action of the current

Question 2

What are the three size categories of Phytoplankton?

Answer 2

Ultraplankton; Nannoplankton; Microplankton

Question 3

What are the typical members of the Ultraplankton size?

Answer 3

Heterotrophic bacteria, autotrophic bacteria, cyanobacteria.

Question 4

What are the typical members of the Nannoplankton size?

Answer 4

Coccoliths, silicaflagelattes

Question 5

What are the typical members of the Microplankton size?

Answer 5

Diatoms; Radiolaria

Question 6

How to phytoplankton such as diatoms protect themselves?

Answer 6

Elaborate silicon shells that are porous to let materials in and out

Question 7

Most abundant form of phytoplankton?

Answer 7

Diatoms

Question 8

What is the importance of phytoplankton frustles

Answer 8

They do not dissolve and they fall to the seafloor to form part of the sediments such as siliceous oozes

Question 9

What is the importance of dinoflagellate pigmentation and bio luminescence?

Answer 9

Formation of red and brown tides - pale blue at night from bio luminescence

Question 10

What is importance of coccolithophorid CaCO3 shell?

Answer 10

Shed during death ans sink to form carbonate ooze

Question 11

What are two important zooplankton groups that ultimately form sediments?

Answer 11

Radiolaria - Silica walls; Foraminifera - Carbonate shells

Question 12

How to radiolarians produce their glass like exoskelatons?

Answer 12

Absorb silica compounds through their lives and secrete well defined geometric networks called tests.

Question 13

How can planktonic forams be used to provide useful infomration for past seawater temperatures?

Answer 13

Individual species often only tolerate a very narrow temperature range. Sea surface species can indicate sea temperatures unlike benthic species which stay relatively stable due to low climate variations

Question 14

How is life distributed from the surface zone to the deep zone

Answer 14

Many herbivores in surface and pycnocline - decrease rapidly to deep zone. Little omnivores in surface zone, increase in pycnocline and decrease half way through deep zone to increase largly in bottom deep zone. Carnivores most abundant in middle of deep zone - fairly similar bottom deep zone and pycnocline to surface.

Question 15

What is max depth of euphotic zone

Answer 15

~200m

Question 16

Where can respiration take place and why

Answer 16

Everywhere in oceans as does not require light

Question 17

What is photosynthesis equation

Answer 17

H2O + CO2 + Nutrients –> CH2O (organic matter) + O2

Question 18

When is organic matter produced in relation to photosynthesis and respiration

Answer 18

When P > R

Question 19

Explain the Marine Biological Pump

Answer 19

Phytoplankton use CO2, sunlight, water and nutrients - produce carbohydrates and oxygen - animals eat phytoplankton - leading to oceanic food web - dead phytoplankton and animals sink to deep ocean - some land on sea floor - material of dead organisms is called reduced carbon - carbon oxidised to yield energy, water and CO2 - 0.4% reduced carbont buried and stored - most is used by animals and bacteria and returned to deep ocean.

Question 20

What general marine areas are net primary productivity per unit area at its highest? And where is production mostly distributed

Answer 20

Coastal zones and upwelings per unit area - mostly distributed in the open ocean

Question 21

What is conservative and non-conservative properties in respect to seawater composition and classification?

Answer 21

Conservative means it is just affected by mixing and non - conservative means it is affected by chemical/biological processes

Question 22

What are the major constituents of ocean sea water (each over 100 ppm)

Answer 22

Choride (Cl-), Sodium, (Na+), Sulfate (SO4-^2), Magnesium (Mg^+2), Calcium, (Ca^2+), Potassium, (K+)

Question 23

What is the average salinity of the worlds oceans

Answer 23

34.7 (34.7 grams of dissolved solids per 1000g sample)

Question 24

What are the ocean trace elements, (<1ppm)

Answer 24

Nitrogen; Lithium; Rubisium; Phospherous; Iodine; Iron; Zinc; Molybdenum

Question 25

How can seasonal changes influence primary production?

Answer 25

Storm weather, light limitation, nutrient limitation - seasonal outflows

Question 26

Why does the Deep Pacific Ocean have more N, P and Si than the Deep Atlantic Ocean?

Answer 26

Deep water concentration increase in response to deep water conveyor/circulation of nutrients