Ochrophyta - Phaeophycaceae

Question 1

difference between class Phaeophycaceae and other Ochrophyta-classes?

Answer 1

• Location of flagella (if present)
• laterally, and NOT (sub)apically

Question 2

thalli in Laminariales and Fucales

Answer 2

• cortex = outermost layer of photosynthetic cells
• medulla = inner layer of non-pigmented cells

Question 3

what does the cortex do?

Answer 3

• produce mucilages
• protects thallus from drying during emersion

Question 4

Answer 4

order: Ectocarpales
- filamentous, uniseriate branched

Question 5

Answer 5

Order: Dictyotales
- parenchymatous thalli
- regular dichotomous branching pattern
- thallus with 3 layers:
1) small cells containing many chloroplasts on each of two outer layers –> involved in PS
2) large pale cells, devoid of chloroplasts, with storage function, in the inner layer

Question 6

Answer 6

Order: Dictyotales

Question 7

Answer 7

order: Desmarestiales
- thalli depending on life cycle
- left +. right: microthalli
middle: macrothalli –> flattened, presence of blades, small blades attached

Question 8

flattened acid kelps

Answer 8

• order: Desmarestiales
• cold temperate waters
• produce sulfuric acid as protection from herbivores

Question 9

Answer 9

Question 10

life cycle Laminariales

Answer 10

1. macrothalli: Sporophyte
   - large
   - foliose
   - parenchymatous
   - highly differentiated
2. microthalli: gametophytic phase

Question 11

Answer 11

Among Desmarestiales there is the species Desmarestia antarctica and two endemic genera of Antarctica: Himantothallus and Phaeurus. These two genera, moreover, are monospecific.

Question 12

Answer 12

order: Laminariales

Question 13

Answer 13

Question 14

organization of sporophyte in Laminariales

Answer 14

Question 15

organization of Laminariales sporophyte
(functions)

Answer 15

Question 16

Answer 16

• order: Laminariales
• organization of sporophyte
• right: trumpet hyphae

Question 17

Answer 17

order: Laminariales

Question 18

Answer 18

order: Laminariales
genus: Laminaria

Question 19

Answer 19

order: Laminariales
genus: Dictyoneurum sp.

Question 20

Answer 20

order: Laminariales
genus: Alaria

Question 21

Answer 21

order: Laminariales
genus: Egregia sp

• stipe flattened and irregularly branched
• blade with outgrowths through most of the length
• outgrowths with diff. functions
  1. pneumatocysts
  2. sterile blades
  3. small blades with sory (sporophylls)

Question 22

Answer 22

order: Laminariales
genus: Alaria

Question 23

Answer 23

order: Laminariales
genus: corda

Question 24

Answer 24

order: Laminariales Genus: Agarum

Question 25

Answer 25

order: Laminariales Genus: Agarum

Question 26

Answer 26

order: Laminariales Genus: Nereocystis

Question 27

Nereocystis luetkeana

Answer 27

Question 28

Answer 28

order: Laminariales genus: Nereocystis

Question 29

Answer 29

order: Laminariales genus: Macrocystis (Giant kelp) - sieve cells form a layer between cortex and medulla - perforation by areas of plasmodesmata in transverse walls of young filaments --> resembles sieve tubes of phloem (higher plant) - callose structures in cross walls of older filaments --> like older sieve plates of phloem (higher plants) ! evolutionary convergence !

Question 30

what plant and what happens?

Answer 30

Macrocystis

Question 32

when in Giant kelp the blade splits, what happens?

Answer 32

Question 33

Answer 33

order: Laminariales genus: Macrocystis

Question 34

Answer 34

order: Laminariales genus: Undaria sp. very competitive, able to substitute other species able to live attached on wood structure characterized by very large size

Question 35

Undaria

Answer 35

Question 36

what about the thalli in adult and juvenile Undaria?

Answer 36

- thalli differ when juvenile and adult - young: thallus flattened, blade irregular, presence of midrib - when getting older: blade pinnaed - corrugated (geriffelte) structure with sporophylls

Question 37

temporal development dynamics of Undaria pinnatifida

Answer 37

undaria is considered an annual species

Question 38

Answer 38

order: Fucales

Question 39

order? genera?

Answer 39

order: Fucales Genera: fucus

Question 40

Answer 40

order: Fucales Genera: fucus gas vesicles in basal part of thallus low motion of water (environment) allows that more gas vesicles develop

Question 41

describe morphology

Answer 41

order: Fucales Genera: fucus they have typically: 1. stipe 2. blades 3. receptacles 4. apices - Receptacles: specialized structures that bear reproductive organs known as conceptacles. These conceptacles contain reproductive cells (gametes or spores)

Question 42

Answer 42

order: Fucales Genera: Ascophyllum

Question 43

Answer 43

order: Fucales Genera: Sargassum

Question 44

Sargassum

Answer 44

- some pelagic species "floating Sargassum" - increase in summer periods due to 1. thalli-division 2. arrival of floating algae do to storms - it hosts biocenosises in the tangles of their organisms

Question 45

what is Sargassum natans? S. fluitans?

Answer 45

- pelagic species of Sargassum - currently considered separate species - some rhodophyta living as epiphytes

Question 46

Answer 46

order: Fucales genera: Sargassum species: muticum long stipe with very short blades but very high amount of gas vesicles (yellowish)

Question 47

Sargassum muticum

Answer 47

Question 48

Answer 48

Sargassum muticum - typical characteristics: many vesicles --> buoyancy

Question 49

temporal development dynamics of Sargassum muticum

Answer 49

Question 50

Phaeophyceae: Ecology and Use?

Answer 50

Question 51

what zone is important for the vegetation of Fucales?

Answer 51

- intertidal zones of rocky coasts

Question 52

Answer 52