Primary Producers

Question 1

What are primary producers?

Answer 1

convert light energy or chemical energy into organic matter
photosynthesis or chemosynthesis

Question 2

What are the main producers in the ocean?

Answer 2

phytoplankton: 90-90%
seaweed: 1-5%
chemosynthetic: 2-5%

Question 3

What is the difference between marine productivity and terrestrial productivity?

Answer 3

about the same amounts, marine only does at a small amount of the ocean (other doesn’t have sunlight so no photosynthesis)

Question 4

What are plankton?

Answer 4

photosynthetic species that drift with the currents
many different sizes

Question 5

What are phytoplankton?

Answer 5

• autotrophic
• generate glucose by photosynthesis
• occupy the euphotic zone
• account for 50% of food made by photosynthesizers on Earth

Question 6

What is the microbial loop?

Answer 6

phytoplankton eaten by zooplankton or killed by viruses
messy organic matter spilled in ocean
heterotrophic bacteria take up this organic matter
bacteria are then eaten by grazers

Question 7

What is bioluminescence?

Answer 7

energy from a chemical reaction transformed into light
energy
glow in the dark dinoflagellates

Question 8

What are harmful algal blooms (habs)?

Answer 8

red tide
harmful toxic red algal bloom

Question 9

Why are inorganic nutrients needed?

Answer 9

required to make large molecules that allow metabolism and to construct skeletons and protective shells

Question 10

What are nonconservative nutrients?

Answer 10

change in concentration with biologic activity
after a bloom, nonconservative nutrients may become depleted
dead organisms sink to the bottom of the ocean upwelling brings nutrients back up

Question 11

What is the compensation depth?

Answer 11

carbohydrate production = carbohydrate consumption
bottom of euphotic zone

Question 12

Where is the level of the most productivity?

Answer 12

euphotic zone
below the surface (otherwise the sun is too strong)
above the compensation depth

Question 13

Where is productivity the highest and what has to be present?

Answer 13

phytoplankton are the base of the food web and productivity
productivity highest near the coast
temperate and southern south polar oceans

Question 14

What are seaweeds?

Answer 14

Multicellular algae (nonvascular)
classification based on color

Question 15

What are vascular plants in the ocean?

Answer 15

mangroves, sea grasses