by: marie-louise posch. kelp kelp – general term for 124 species of brown algae. classified in the...
TRANSCRIPT
By: Marie-Louise Posch
KelpKelp – general term for 124
species of brown algae. Classified in the Kingdom
Chromista or Protista.http://www.youtube.com/wat
ch?v=Y9eyK6C9nDA (0:28)
http://www.youtube.com/watch?v=naYu4m3b6cw (3:04)
Kelp Forest
StructureThe kelp plant has three parts:
the blade (the leaf-like structure), the stipe (the stem-like structure), and the holdfast (root-like structure)
Holdfasts grip substrates Blades are buoyed by air
bladdersDo not dry up at low tide
because cell walls contain a mucilaginous, water retaining material Kel
p
FunctionKelp grows in forests, which can be made
of more than one species Provides habitat and food for marine life
including fish, invertebrates, marine mammals, and birds
A good source of protein, iodine, and ironProtects the body from heavy toxic metals The sodium alginate in kelp helps prevent
absorption of radioactive strontium 90
Brown AlgaeThe largest, most complex
type of algaeContains chlorophyll a and
c The pigment fucoxanthin
gives it its colorAir bladders help the
blades float to allow for maximum sunlight absorption.
Brown Algae
StructureHave chloroplasts
surrounded by four membranes, suggesting an origin between basal eukaryotes and another eukaryote
Develop into multicellular forms with differentiated tissues, but they reproduce by flagellate spores and gametes Brown
Algae
FunctionFood source for fish, gastropods, and sea
urchins.Benthic (bottom-dwelling) organisms benefit
when pieces of it sink to the sea floorCommon uses include food thickeners,
stabilizers, and fillers. Also used in pharmaceuticals
Contains chemicals called alginates that are used to thicken certain products like toothpaste and ice cream.
Review QuestionsWhat are the three parts of a kelp plant?
blade, stipe, and holdfastWhat is the function of an air bladder?
help the blades float to allow for sunlight absorptionName some common uses of brown algae by people
food thickeners, stabilizers, pharmaceuticals, and fillersName two ways kelp benefits marine life?
Food source and habitatHow does brown algae reproduce?
by flagellate spores and gametesWhat is unique about the structure of brown algae?
Have chloroplasts surrounded by four membranes