Week 2: Primary productivity

Question 1

Major components of protein and nucleic acids

Answer 1

Nitrogen

Question 2

Nitrogen can be available as

Answer 2

Nitrate and Ammonium

Question 3

Component of cell walls, ATP, Nucleic Acids

Answer 3

Phosphorus

Question 4

Phosphorus can be available as

Answer 4

Phosphate (Inorganic Phosphorus)

Question 5

Found in Diatom cell walls

Answer 5

Silicon

Question 6

Silicon available as

Answer 6

Silicate

Question 7

Important component of chlorophyll

Answer 7

Iron / Micro-nutrient

Question 8

Maximum concentrations of nutrients in temperate seas/oceans

Answer 8

Nitrate - 20
Ammonium - 100
Phosphate - 2
Silicate - 175
Iron - 1.1

Question 9

Primary limiting nutrient in the ocean

Answer 9

Nitrogen

Question 10

Secondary limiting nutrients in the ocean

Answer 10

Phosphorus and iron

Question 11

Limits growth of diatoms and is often depleted following blooms

Answer 11

Silicate

Question 12

High levels of productivity are observed where

Answer 12

Where sufficient light and nutrients are available

Question 13

Largest percentage of marine fauna

Answer 13

Algae

Question 14

What are algae

Answer 14

1. Eukaryotic (cells with a nucleus)
2. Members of kingdom protista
3. Are not plants

Question 15

Monophyletic groups

Answer 15

Different species that are collectively traced from a single ancestor

Question 16

Paraphyletic groups

Answer 16

Different species diverged at different times and don’t have a common ancestor

Question 17

Defining characteristics of algae

Answer 17

1. Flagella at some stage of life cycle (except for reds)
2. Reproduce by spores
3. No roots
4. Mostly Photosynthetic (autotrophic)
5. Mostly aquatic, mostly marine

Question 18

Algal classification

Answer 18

1. Photosynthetic pigments
2. Characteristics of flagella
3. Cell wall material
4. Structure (Filaments, multicellular forms, colonies/single)

Question 19

Chlorophyta

Answer 19

Green algae, are the ancestors of kingdom plantae

Question 20

Ochrophyta/Phaeophyta

Answer 20

Brown algae, includes diatoms and brown seaweeds

Question 21

Rhodophyta

Answer 21

Red algae, are the oldest and most diverse algal group

Question 22

Dinophyta

Answer 22

Dinoflagellates, single-celled phytoplankton with flagella

Question 23

Major primary producers and important bloom-forming phytoplankton

Answer 23

Diatoms and Dinoflagellates

Question 24

Diatoms characteristics

Answer 24

1. > 5,600 species known to exist
2. Major component of coastal and open ocean phytoplankton
3. Essential nutrients for growth - silica, iron, nitrogen
4. Silica cell wall or frustule
5. Accessory pigment - Fucoxanthin

Question 25

Diatom centrales description

Answer 25

Areole arranged in radial pattern

Question 26

Diatom pennales description

Answer 26

Areole bilaterally symmetrical along a longitudinal axis

Question 27

Sexual reproduction in diatoms

Answer 27

1. The valves of the frustule seperate 2. New valve grows within the old one, = smaller frustules 3. Reach around 1/4 of the original size and sink 4. Sexual reproduction produces Auxospore -> full-sized cell

Question 28

Dinoflagellates characteristics

Answer 28

1. 2000 species 2. 90% marine, mostly unicellular 3. Thick-walled resting zygote formed via sexual reproduction 4. 40% of species have no chloroplasts 5. Pigment and Peridinin, Chl c 6. Thecal plates secreted within an outer cell membrane 7. Posterior and transverse flagella

Question 29

Dinoflagellates name origination

Answer 29

From the greek word "dinos" to whirl

Question 30

Harmful algal blooms (HABS) characteristics

Answer 30

1. Toxic and non toxic harmful blooms occur 2. Caused by microscopic plankton and macroalgae 3. Conditions (low mixing, high nutrients, warm temperatures and high light) leading to exponential growth 4. HABs can give major implications for food safety, productivity and rates of mortality in aquaculture.

Question 31

Ciguatera poisoning

Answer 31

1. Affects 50,000 people/year who harvest fish from tropical and subtropical reef lagoons (0.1-12% die) 2. Ciguatoxin and other similar compounds responsible 3. Reversal of temperature sensation, muscular aches, dizziness, anxiety, sweating, and a numbness and tingling of the mouth and digits

Question 32

Macroalgae/seaweed

Answer 32

1. Multicellular macroscopic 2. Vast majority are photosynthetic 3. Key primary producers in coastal seas

Question 33

Chlorophyta characteristics

Answer 33

1. Most closely related to vascular plants 2. Cellulose cell wall 3. Pigment chlorophyll b

Question 34

Phaeophyta Characteristics

Answer 34

1. Filamentous to complicated kelp species 2. Cell wall made of Alginate 3. Accessory pigment Fucoxanthin

Question 35

Rhodophyta Characteristics

Answer 35

1. Absense of flagella on spores and gametes 2. Accessory pigments, phycoerythrin, phycocyanin 3. Cell walls contain agar and carrageenan 4. Deepest known photosynthetic organism

Question 36

Why are algae importanrt

Answer 36

1. Major producers - only 1% of plant biomass - around 40% photosynthesis on earth 2. Bottom of the food web 3. Habitats for animals 4. Food 5. Toxic algal blooms 6. Food and products

Question 37

Autotrophs vs heterotrophs

Answer 37

1. Autotrophs can produce their own food 2. Heterotrophs are consumers who depend on other sources for food

Question 38

Marine angiosperms

Answer 38

1. Flowering plants 2. Advanced vascular plants that reproduce with flowers and seed

Question 39

Only marine higher plant

Answer 39

Seagrasses

Question 40

Cause of decline in kelp forests

Answer 40

Warm, salty, nutrient-poor water travelling to polar regions

Question 41

Dominant marine primary producers

Answer 41

Algae

Question 42

Dominant marine flora

Answer 42

Algae

Question 43

Importance of seaweeds and seagrasses

Answer 43

1. Important primary producers 2. Key habitat-forming species