Transcript Multicellular Primary

Multicellular Primary
Producers ~
Seaweeds
Seaweeds –
marine Macroalgae
• Three types – red,
brown, and green algae
• Most species are benthic
• Can be fouling
communities – live on
bulkheads, pilings or
artificial surface
• Distinguished by the
type of pigment used for
photosynthesis and the
composition of the cell
wall.
• Abiotic factors – light, temp.,
tides, wave action, salinity,
nutrients
• Chromatic adaptation – ability
of plants to alter
photosynthetic pigments in
response to light conditions
• Perennials – live longer than a
year
Seaweeds – marine Macroalgae
Red Algae – phylum Rhodophyta
Red algae
• Mostly marine
• Epiphytes – live on other
plants
• Adaptations to predation
– Make thallus less edible
– Changing growing
patters(out instead of up)
– Complex life cycles
• Uses
– Agar culture material
– Thickening agents in foods
and pharmaceuticals
– Carrageenan – binding
agent in ice cream, pudding
and salad dressing
– Cosmetics
– Sushi, soups and seasonings
– Animal feed
– fertilizer
Red algae life cycle
Brown algae –
phylum
Phaeophyta
Brown algae- kelp, sargassum
• Mostly marine
• Mostly benthic
• Microscopic to 100
meters
• Very defined holdfast,
stipe and blade
• Gas filled bladders
• Uses
– Thickening agents in
textiles, dental and
cosmetics and food
– Human consumption
– Cattle feed
Brown algae- Adaptations
- thin, broad blades allow for floating on top of water where they can
use light to photosynthesize
- anchors allow them to stay in one place and not float off to places
where the conditions may not be as advantageous to their survival
- waxy blades prevent them from drying up
- pigment fucoxanthin well adapted for absorbing wavelengths of
light in their environment to maximize efficiency of photosynthesis
- reproduction by flagellate spores allow offspring to be anchored in
places where the environment is equally advantageous for their
survival.
an edible brown seaweed used,
typically in dried form, in Chinese
and Japanese cooking
Kombu Japanese Kelp dish
Seaweed laid out for making Maki
rolls
Green algae –
phylum
Chlorophyta
Example
sea lettuce
• Very few marine macroalgae
• Most are fresh water and phytoplankton
• Adaptations to predation:
– Rapid growth and reproduction
– Can occupy small crevices predators can’t
– Deposits calcium carbonate in
cell walls
– toxins