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

Kelp

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