Lab #4: Stramenopiles

Question 1

Stramenopila Characters (supergroup)

Answer 1

Cell: Eukaryotic

Flagella: Heterokont

Chloroplast: Double membrane with 2 added layers of chloroplast ER, thylakoids in stacks of three, primary pigment is chlorophyll a, accessory pigments are chlorophyll c, ß-carotene, xanthophylls

Level of Organization: All levels, unicellular, colonial, filamentous and parenchymatous

Reproduction: Highly Variable

Habitat: Aquatic in marine or fresh water

Question 2

Chrysophyceae Characters (Class)

Answer 2

Cell: Eukaryotic

Cell covering: A cell wall made of cellulose. Loricas and silicified scales and walls occur in some species

Flagella: Two flagella (heterokont)

Chloroplast: Double membrane with two added layers of chloroplast ER,
thylakoids in stacks of three, primary pigment is chlorophyll a,
accessory pigments are chlorophyll c, ß-carotene, xanthophylls
(especially fucoxanthin)

Food storage: Lipids, leucosin, chrysolaminaran

Level of organization: Form is unicellular to colonial

Reproduction: Asexual by cell division, sexual reproduction is isogamous,
anisogamous

Habitat: Fresh and marine water

Question 3

Xanthophyceae Characters (Class)

Answer 3

Cell: Eukaryotic

Cell: covering Cell wall is composed of cellulose

Flagella: Certain motile cells (zoospores) have two unequal flagella
(heterokont)

Chloroplast: Double membrane with two added layers of chloroplast ER,
thylakoids in stacks of three, primary pigment is chlorophyll a,
accessory pigments are chlorophyll c, ß-carotene, xanthophylls
(especially diadinoxanthin and diatoxanthin but not fucoxanthin)

Food storage: Glucans, fat, and oils

Level of organisation: Unicellular to filamentous

Reproduction: Asexual via zoospores, sexual is isogamous or oogamous. Life
cycle: zygotic meiosis

Habitat: Mostly aquatic in fresh water, some are marine

Question 4

Coenocytic

Answer 4

Multinucleate mass of protoplasm
The cells arent separate but instead many nuclei connected

Question 5

Vaucheria spp.

Answer 5

Siphonaceaous alga resembled green filamentous algae, but it lacks chlorophyll b

These alga are coenocytic

Question 6

Tribonema spp.

Answer 6

This differs from Vaucheria spp. because Tribonema spp. is filamentous