BIOL3711 Lecture Notes - Lecture 5: Meiosis, Zygote, Phycoerythrin
26 Jun 2018
School
Department
Course
Professor
Brown Algae and Red Algae
Brown Algae
Characteristics
Multicellular
About 1500-2000 speceis
Size:
oFew microns to meters
Cell wall:
oCellulose
CHLOROPLAST:
oChlorophyll a and c, NO b
oAccessory: B-carotene and fucoxanthin
oGolden colour
oDiscoid shape or ribbon-like
Pyrenoid (in chloroplast, carbon fixation and starch production)
oPear-shaped
FLAGELLA:
oONLY the reproductive cells have flagella
oFree-living vegetative cells do NOT
Food reserve:
oLaminarin (polymer of glucose)
Alternation of generation in life history:
oSporophytes
A spore producing phase in an alternation of generation, usually
DIPLOID
oGametophytes
Gamete-producing phase, usually HAPLOID
oIsomorphic generation
Sporophytes and gametophytes are similar in structure and
general appearance
oHeteromorphic generation
Sporophytes and gametophytes are DIFFERENT in structure
and appearance
Classification
Phylum: Phaeophyta
oClass: Phaeophyeae
Order: Ectocarpales (with isomorphic generation)
The orders of brown algae are divided on the BASIS of LIFE
HISTORY
Genus: Ectocarpus
Grows on rocks
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Chloroplast: chlorophyll a and c, no b, accessory: b-carotene and fucoxanthin, golden colour, discoid shape or ribbon-like. Pyrenoid (in chloroplast, carbon fixation and starch production: pear-shaped. Flagella: only the reproductive cells have flagella, free-living vegetative cells do not. Food reserve: laminarin (polymer of glucose) Alternation of generation in life history: sporophytes. A spore producing phase in an alternation of generation, usually. Gamete-producing phase, usually haploid: isomorphic generation. Sporophytes and gametophytes are similar in structure and general appearance: heteromorphic generation. Sporophytes and gametophytes are different in structure and appearance. The orders of brown algae are divided on the basis of life. Basal (base, bottom) filaments grow over the substrate in a compact mass providing attachment. More openly branching filaments are arising from the base. Life history: definitions, asexual, diploid phase, sporangium = receptacle where asexual spores are formed, zoospore = motile asexual spore with flagellum, summer (pluri): Sporophytes produce plurilocular sporangium (cid:0) zoospore (2n) (cid:0) sporophytes (2n: winter (uni)
