Phytoplankton Flashcards

Question

Pelagophyceae

Answer 1

Unicellular, brown tides, Grow so dense that they shade seagrasses, thus killing them.

Answer 2

Primitive green flagellates with Chl a & b 4-8 flagella Covered with scales Coastal waters & tidepools

Answer 3

flatworm lives in sand and has algal symbiont Prasinophyte in tissue Forms green patches on sand and as tide comes in disappears into sediments Worms rely on photosynthate Older worms eat the algae from tail to head then die and releases eggs with alga

Answer 4

Two flagella, chl a & c & fucoxanthan Vertically migrates 10-15 m daily Has cyst stage Toxic to fish, especially caged ones. In ’72 Chatonella killed $500 mil of Yellow tail fish in Japan

Answer 5

“Golden Algae” Very diverse group, related to Prymnesiophytes but with no haptonema Pigments: Chl a & c, B Carotene, Fucoxanthan, Diadinoxanthan, Violaxanthan Storage: Chrysolaminarin Most freshwater, found in tide pools Usually 2 unequal flagella or just one statospore (of silicon) for hard times

Answer 6

``` Chl a & c, Phycocyanin & phycoerythrin 2 equal or unequal flagella Storage: Starch Thylacoids in pairs Have a gullet lined with trichocysts Very abundant in brackish water ```

Answer 7

Basically a protozoan that has acquired chloroplasts Most are motile & unicellular ~ 7 μm-2 mm in size Some are colorless and can be phagotrophic or (heterotrophs) Some totally autotrophic Some are mixotrophs (both auto and heterotrophic) and can both photosynthesize and consume other phytoplankton Some are symbionts (in corals & other organisms) Some are parasites

Answer 8

Chl a & c, B Carotene, Peridinin (signature pigment), rarely fucoxanthan & diatoxanthan About 2000 species (90% marine) Thylacoids in stacks of 3 Chloroplasts enclosed by double unit membrane

Answer 9

Prorocentrales (2 cellulose plates) Dinophysidales (2 large cellulose plates & 12 small plates) Peridiniales (many plates but some are without plates “naked”)

Answer 10

if they do not have any cellulose plates

Answer 11

trichocysts

Answer 12

Swimmers are haploid vegetative cells When conditions become unfavorable, gametes are formed and a hystrichospheroid cyst (diploid) forms, with resistant sporopollinin cell wall, and falls to sediments When conditions favorable, it excysts, undergoes meiosis and new vegetative cells formed Pellicle cysts can also be formed for short term survival.

Answer 13

Reduces predation, Flashing dinos when copepods try to eat them attract a predator

Answer 14

cellulose (armor)

Answer 15

new moon, reduces predation

Answer 16

- food - -Many dinoflagellates vertically migrate into the nitricline at night to take up NO3 and to upper euphotic zone in morning to photosynthesize in the daytime. Shown is dino vertical migration in mesocosm

Answer 17

and provides a route map through the variations of phytoplankton composition in time and space, and the causes of these variations.

Answer 18

Consist of ~ 12,000 species Plankton or Periphyton (attached) 4-5 μm- >1 mm Pigments: Chl a & c, B carotene, Fucoxanthan, Diadinoxanthin, Diatoxanthin Consist of two orders, Centrales & Pennales Chloroplast has thylacoids in groups of three Storage product is chrysolaminarin (B 1-3 linked glucose units) and lipids (5-15% dry wt young-40-50% when old)

Answer 19

Silicon & Silicate & Silica

Answer 20

the hard and porous cell wall or external layer of diatoms Nutrients are exchanged through holes in the frustule. Holes are called punctae in pennates, and in centrics there are sieve like structures (areolae) Outer buffer zone of frustule has a structural carbohydrate layer plus lipids and an amino acid template with a high serine content Pennates can move if attached to something. The raphe is the long slit down the middle of the frustule and is involved in movement. Centrics have no raphe.

Answer 21

Centrales & Pennales

Answer 22

frustule is heavy, regulate the ionic content of the cell sap in vacuole. They replace heavy ions such as Ca & Mg with lighter ions such as Na or K. This replacement actually makes them buoyant. Shape of the cell influences sinking velocity and elaboration of cell shape increases surface area ratio and this increases viscous drag as it sinks

Answer 23

When a diatom divides, each of the original halves become the epitheca. Thus half of the cells become progressively smaller

Answer 24

original large size by production of auxospores. Auxospores produced after sexual recombination

Answer 25

a supply of silicic acid, hence typically occur in coastal areas.

Answer 26

where there is lots of silicic acid... coastal areas which receive riverine input Upwelling regions also have high diatom abundance and silicic acid concentrations are higher in deep water which upwells Antarctic waters of the Southern Ocean have high concentrations of silicic acid and diatoms Sedemented as opal (a biogenic mineral)

Answer 27

When a bloom is over and nutrients are exhausted, diatoms form resistant resting spores. Spores allow a short term (months) survival in sediments

Answer 28

In 2 years Jane Gallager (J. Phycol 1980 vol 16:464) isolated 457 clones of Skeletonema costatum. Clones isolated in winter were genetically distinct from summer ones They were as different as two different species but morphologically they all were identical. No single isolate is representative of all populations

Answer 29

in order to avoid becoming smaller and smaller (MacDonals Rule) they need to reproduce sextually

Answer 30

Diatoms dominate when silicic acid concentrations are above 2 uM they have a hard time at lower concentrations

Answer 31

The diatoms synthesize aldehyde molecules which arrest mitosis in eggs.

Answer 32

Silaffins are involved in the formation of the cell walls of diatoms

Answer 33

Aerolae-- A general term for a round or oval pore in the silica wall of a diatom Punctae -- the plural form