2. Seaweeds
Seaweeds!!!
Come in all kinds of interesting
Shapes and sizes!
⢠some are delicious!
⢠some are poisonous
⢠Some have weird names
⢠Come in all sorts of colors
3. Seaweed Structure
⢠Thallus-body
⢠Lack vascular tissue -Do not
have roots, stems, or leaves
⢠Holdfast -The structure
that attaches the seaweed
to the substrate
⢠Stipe-stem-likestructure
4. Phylum Chlorophyta (green algae)
⢠Contain chlorophylls a and b for photosynthesis
⢠Most are freshwater
⢠Ecologically important
â food source
â Contribute to coral reef formation
â Some are invasive
5. Green algae structure
⢠Most unicellular
⢠Marine species have coenocytic thallus-
containing more than 1 nucleus
â Occurs by cell growing
â nucleus divides
but cell never
divides
6. Reproduction of Algae
⢠Sexual
⢠Gametes released from gametophyte 2 flagella
⢠spores released from sporophyte- 4 flagella
8. CFU: Green Algae
⢠Are green algae unicellular or multicellular
⢠Autotrophic or heterotrophic
⢠What is an important organelle in
photosynthesis
⢠How does green algae grow in length?
â Same cell, division of nucleus
⢠What is the function of the Stipe?
10. Phylum Rhodophyta (red algae)
⢠Primarily marine
⢠Most diverse among seaweeds
⢠Cholorphylls a and d, pigments:
phycoerythrins and phycocyanins
⢠Not always red in color- can appear yellow to
black
12. Reproduction
⢠Can vary from simple
to complexâŚbut 2
unique featuresâŚâŚâŚ..
1. Lack flagella on
spores and gametes
2. 3 multicellular stages
1. Carpospore-unique
to red
algae
13. Ecological Roles
⢠Porphhra- used as food in oriental dishes
⢠Seasonal food source for
urchins, mollusks, fish, and crustaceans
⢠Some grow on other plants or animals
⢠Help form base of coral reef
⢠Agar- used as a thickening agent in foods such
as ice cream, pudding, and salad dressings
⢠Used in cosmetics for creamy foundations
14. CFU: Red Algae
⢠Heterotrophic or Autotrophic?
⢠Multicellular or unicellular
⢠What are the two unique stages?
⢠What organisms feed on red algae?
16. Phaeophyta (brown algae)
⢠Mostly marine
⢠Higher diversity than green but less diverse
than red
⢠Size: from microscopic to kelps (100 meters)
⢠Chlorophylls a and c and pigment fucoxanthin
⢠Mostly in high latitudes
⢠Large flat leaf-like blades with bladders help
bouy plant toward light
⢠Representative species Sargassum, Fucus
17. reproduction
⢠Gametophyte is
eliminated from
life cycle (difference
from Chlorophyta and
Rhodophyta)
⢠Egg develops
root-like
structures
(rhizoids) after
fertilization
18. Ecological role
⢠Habitats for a variety of marine life
⢠Harvested for thickening agents used in
dentistry, cosmetic, and food industries
⢠Previously iodine was extracted and put into
table salt (iodized salt) to prevent a goiter
19. ⢠Excessive nutrients
â Runoff from fertilizer Human Impacts
⢠Causes huge algae
blooms!
â When algae dies off
decomposers consume
majority of the oxygen in
the environment
â Eutrophication
⢠Kills off fish and marine
life
20. CFU: Algae
⢠What macromolecule allows algae to live in
marine environments without swelling?
⢠What causes algae blooms?
⢠What is this process called?
⢠What are the harmful effects of algae blooms?
22. Salt Marsh Plants and Sea Grasses
⢠Salt marshes are in Estuaries
â The kidneys of the coasts
⢠Nursery for small fish
â 75% of commercial fish are hatched in estuaries
⢠Estuaries are severly affected by humans
â Coastal development
â Pollution
â Eutrophication
⢠Protect us from storms
23. Phylum Anthophyta
⢠Seagrasses, salt marsh plants, mangroves
⢠Ecological Roles- Primary
producers, habitats, stabilizing sediments
⢠Help slow down erosion
⢠Have to deal with extreme changes in salinty
and oxygen
Mixing of salt and fresh water
Eutrophication
24. Sea grasses (marine flowering plants)
⢠Related to lilies
⢠Reproduce by pollination of seed; Male and female flowers on
separate plants contain pollen
⢠Literally look like grass
⢠Food for manatees and sea turtles
⢠Can live up to 100 meters below sea level
26. Salt Marsh Plants
⢠Adapted to high levels of salinity and tidal action
⢠Found in estuaries â level of succession based on salinity and tidal
tolerance
⢠Species native to Jacksonville
â SpartinaAlternaflora
â BatisMaritima
â Spartina patens
â Juncus
â Salicorniavirginica
27. Mangroves
⢠Found in south of St. Augustine to Key West
⢠3 genra local to Florida
â Rhizophora mangle âred mangle-----prop roots
â Avicennia germinans â black mangle---
pneumatophores
â Laguncularia racemosa- white mangle
⢠Distinctive by their root system and pods
28. Mangroves: Highly adaptive
⢠Use active transport to
regulate water levels in
their roots
⢠Live in anaerobic mud
â Why they stand above
the water
⢠Protect coral reefs from
eutrophication
â Filter, kidney
30. Mangrove reproduction
⢠Flowers pollinated by wind or bees
⢠Embryo grows on the plant in a propagule
(similar to seed)
⢠Propagule eventually falls from parent and is
carried by current until it settles and takes
root