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Marine Algae
Maritime Algae
Seaweed is a term applied to multicellular, marine algae which are huge enough to be watched by the eye unaided. Some deserve to grow to up to 60 metres in size. Seaweeds include members of the red, brvery own and also green algae. They are members of the kingdom Protistan interpretation they are not Plants. They perform not have the vascular system (interior deliver system) of plants and perform not have roots, stems, leaves and also flowers or cones. Like plants they use the pigment chlorophyll for photosynthesis however likewise contain various other pigments which might be coloured red, blue, brvery own or gold. They are split into 3 groups:

Brown Algae (Phaeophyta) Green Algae (Chlorophyta) Red Algae (Rhodophyta)

Diversity in marine algae

Blue-green algae are not marine algae. They are in a team dubbed cyanobacteria and also are even more carefully regarded bacteria. Some cyanobacteria kind brvery own, green, red or purple tufts on coral reefs.

To survive seaweeds require salty or brackish water, sunlight and also a surconfront to affix themselves to. Due to the fact that of these components they are generally found in the littdental zone (this contains the intertidal zone but mainly exoften tends out a lot further). They are generally found on rocky fairly than on sand also or shingle shores.

You are watching: Why do large algae have a holdfast?

Seaweeds are a food resource for marine pets such as sea urchins and also fishes, and are the base of some marine food webs. They likewise carry out shelter and a house for numerous fishes, invertebrates, birds and mammals.

The kelps develop dense woodlands which support whole underwater areas giving both food and sanctuary. Intertidal seaweeds have the right to be exposed to many kind of environmental stresses consisting of drying out when not under water, temperature and also salinity changes and wave action.

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Kelp (a brown alga) woodland

Structure of seaweeds

Thallus: the whole body of a seaweed. Lamina: a flattened structure that is resembles a leaf. Sorus: a cluster of spores spore. Air bladders: a hollow, gas-filled framework organ which helps the seaweed float, found on the blade). Other seaweeds (e.g. kelp) have actually floats which are situated between the lamina and stipe. Stipe: a stem-like structure, not all seaweeds have these. Holdfast: a devoted structure on the base of a seaweed which acts as an “anchor” enabling it to connect to a surface (e.g. a rock). Haptera: finger-choose extensions of holdquick anchoring to benthic substrate.

Seaweeds play a very necessary functions in many marine neighborhoods. They are a food resource for many kind of marine animals such as sea urchins and fishes, and form the base of some food webs. They additionally carry out shelter and a residence for plenty of fishes, invertebrates, birds, and mammals.

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Structure of marine algae

Seaweed Reproduction

Seaweed life and reabundant cycles deserve to be rather complex. Some seaweeds are perennial, living for many years, while are annuals. Annual seaweeds primarily start to prosper in the spring, and also proceed throughout the summer. Some red seaweeds have actually a life span of 6 to 10 years.

Seaweeds deserve to reproduce sexually, by the joining of specialized male and also female reproductive cells, called gametes. After they are released from the sporophyte, the spores resolve and also grow into male and also female plants called gametophytes. The gametophytes create gametes (sperm or eggs). The sperm and eggs are either preserved within the gametophyte plant body, or released right into the water. Eggs are fertilized when the sperm and also egg fusage together, and also a zygote is developed. Zygotes develop and grow into sporophytes, and also the life cycle proceeds.

Seaweeds display a range of various refertile and also life cycles and the description over is only a basic instance of one kind, referred to as altercountry of generations. In a couple of species there is an alternating sex-related and asex-related reabundant process through eincredibly generation. Seaweeds have the right to likewise recreate asexually via fragmentation or department. This occurs as soon as components of a plant break off and develop directly into new individuals. All offspring resulting from asexual remanufacturing are clones; they are genetically the same to each other and also the parent seaweed.

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Reproduction of algae

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Carrageean products

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Agar plates

Uses of Seaweed

Seaweeds location food source for human beings especially in East Asia, it is the majority of typically associated through Japanese food. Seaweeds also are supplied to make a variety of food additives such as alginates and also carrageenan which is offered in food preparation and also baking as a vegetarian different to gelatine.

Many type of seaweeds are offered as medicine. Alginates are provided in wound dressings and in the manufacturing of dental moulds and also agar is provided exceptionally widely in Microbiology to assist prosper bacterial cultures.

See more: An Example Of A Folk Custom Used To Diffuse Information About Agriculture Is

Seaweeds are ingredients in toothpaste, cosmetics and paints and also are offered in commercial commodities such as paper coatings, adhesives, dyes, gels, explosives and also many type of more.

Much of the oil and also natural gas we use this day formed from seaweeds which partly dewritten on the sea floor many kind of countless years back.

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Japanese food supplies seaweeds generally - Kombu a brown alga and also Kim nori a red alga

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Nori

References

http://en.wikipedia.org/wiki/Seaweed /www.oilgae.com/algae/types/marine_algae/marine_algae.html www.reef.crc.org.au/discover/plantsanimals/algae/index.html /www.cornishseaweedresources.org/lifecycle.htm http://marinelife.around.com/od/plants/tp/typesofalgae.htm /www.reef.crc.org.au/discover/plantsanimals/algae/index.html http://en.wikipedia.org/wiki/Brown_algae http://en.wikipedia.org/wiki/Red_algae http://en.wikipedia.org/wiki/Green_algae www.seaweed.ie/algae/chlorophyta.html

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Red Seaweed Image © Brent Wilboy through Flickr

Algae: The World"s Many Important Plants Believe it or not, your life depends on algae! Join Scripps" Institution"s Russell Chapmale as he discusses the crucial duties algae have actually played in the breakthrough of life as we understand it. Series: "Perspectives on Ocean Science" <12/2006>

Thanks toI would certainly sincerely choose to thank the many kind of members of the Flickr community that have actually offered me permission to use their wonderful imeras for this unit. Their contributions really make this unit come alive! Next: Brown Algae...

Introduction
Brvery own Algae
Eco-friendly Algae
Red Algae
Coralline Algae
Picture Gallery