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Ulva lactuca

Ulva lactuca

Scientific classification
Domain: Eukaryota
Kingdom: Protista
Phylum: Chlorophyta
Class: Ulvophyceae
Order: Ulvales
Family: Ulvaceae
Genus: Ulva
Species: U. lactuca
Binomial name
Ulva lactuca
Linnaeus, 1753

Ulva lactuca Linnaeus, a green alga in the Division Chlorophyta, is the type species of the genus Ulva, also known by the common name sea lettuce.



Ulva lactuca is a thin flat green alga growing from a discoid holdfast. The margin is somewhat ruffled and often torn. It may reach 18 cm or more long though generally much less and up to 30 cm across.[1] The membrane is two cells thick, soft and translucent.[2] and grows attached, without a stipe, to rock via a small disc-shaped holdfast.[3] Green to dark green in color this species in the Chlorophyta is formed of two layers of cells irregularly arranged, as seen in cross section. The chloroplast is cup-shaped with 1 to 3 pyrenoids.


New Zealand Plant[4]


Ulva lactuca is very common on rocks and on other algae in the littoral and sublittoral on shores all around the British Isles[5] with a world-wide distribution.[3] It is particularly prolific in areas where nutrients are abundant.[6] There are other species of Ulva which are similar and not always easy to differentiate.

Life history

The sporangial and gametangial thalli are morphically alike. The diploid adult plant produces haploid spores by meiosis, these settle and grow to form haploid male and female plants similar to the diploid plants. When these haploid plants release gametes they unite to produce the zygote which germinates, and grows to produce the diploid plant.[7][8][9]


U. lactuca is locally used in Scotland in soups and salads.[10] [11]


  1. ^ Ulva lactuca. Gettysburg College. Retrieved on 2007-12-28.
  2. ^ Ulva lactuca. University of Rhode Island. Retrieved on 2007-12-28.
  3. ^ a b Burrows, E.M. (1991) Seaweeds of the British Isles. Volume 2 Chlorophyta. Natural History Museum, London. ISBN 0 565 00981 8
  4. ^ Sea lettuce. University of Auckland. Retrieved on 2007-12-28.
  5. ^ Hardy, F.G. and Guiry, M.D. (2006). A Check-list and Atlas of the Seaweeds of Britain and Ireland. British Phycological Society, London. ISBN 3 906166 35 X
  6. ^ Michael Guiry. Overview of Ulva lactuca ecology. the Seaweed Site. Retrieved on 2007-12-28.
  7. ^ Abbott, I.A. and Hollenberg, G.J. (1976). Marine Algae of California. Stanford University Press, California. ISBN 0 8047 0867 3
  8. ^ Mondragon, J. and Mondragon, J. (2003). Seaweeds of the Pacific Coast. Sea Challengers, Monterey, California ISBN 0 930118 29 4
  9. ^ Life-history diagram for Ulva lactuca, MBARI, accessed 13 June 2007
  10. ^ Indergaad, M and Minsaas, J. 1991 in Guiry, M.D. and Blunden, G. 1991. Seaweed Resources in Europe: Uses and Potential. John Wiley & Sons ISBN 0 471 92947 6
  11. ^ Ulva Recipes. Monterey Bay Aquarium Research Institute. Retrieved on 2007-12-28.

Further reading

  • Hayden, H.S., Blomster, J., Maggs, C.A., Silva, P.C., Stanhope, M.J. and Waaland, J.R. (2003) Linnaeus was right all along: Ulva and Enteromorpha are not distinct genera. Eur. J. Phycol. 38, 277-294.
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Ulva_lactuca". A list of authors is available in Wikipedia.
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