Marine Biology

Salt excretion

removal of salt through glands located on each leaf that concentrate the salt and allow it to crystallize on the leaf surface (right photo). Ex: Black mangroves

Brown algae

Chlorophyll a, c and carotenoids (flucoxanthin and other) Major food reserve laminarian oil Primary producers; dominant component of kelp forests ~ 1500 species, almost all marine Some microscopic, most larger - to 300+ feet Prefer shallow, cold waters Contain chlorophyll A and C and fucoxanthin Typical body of holdfast, stipe and blades Source of algin Examples: kelp, Fucus (bottom right), Sargassum The color is due to a preponderance of yellow-brown accessory pigment, particularly fucoxanthin over chlorophyll 1800 known species are marine Often dominant primary producer on temperate and polar rocky coasts and include the largest and most complex seaweeds. The brown algae have yellow-brown accessory pigment in addition to chlorophyll. They include the largest and structurally most complex seaweeds The simplest brown algae have a finely filamentous thallus. The thallus is flat and branched in dictyota The thallus is fan shape and lightly calcified in padina Padrina and dictyota are both tropical and subtropical. The thallus of desmarestia is branched in many ways, this is found usually in cold waters. It ranges from the Antarctic to temperate shores elsewhere. Most species have gas-filled floats, known locally as rockweeds or wracks is found on the Atlantic and Pacific coast. The knotted rockweeds is free-floating or attached to rocks Sargasso weed has spherical air bladders that keep the small, leaf-like blades afloat at the sea surface. Found in Sargasso sea, an area in the Atlantic north Sargassum is a species of brown algae found in the Atlantic between North America and Europe as well as the Gulf of Mexico Massive floating mats of Sargassum provide habitat for countless species of fish, marine mammals, birds and invertebrates This community is known as the Sargasso Sea Like the kelp forests, the importance of this community cannot be overstated. The kelps found in temperate and polar locations are the largest of the alga In some species, like the giant kelp, each individual can be hundreds of feet in length This growth provides habitat for countless species of fish, marine mammals, birds and invertebrates - this community is known as the kelp forest. Kelp forests are among the most productive (and important) marine habitats. The kelps are the most complex and largest of all brown algae. Most are found at low tide levels in temperate and subpolar latitudes. In these environment they can occur in great abundance providing food and shelter for many other organisms. Some kelp consists of a large blade up to 3 meter. Their blades are harvested for food. Several blades can grow from a single holdfast. Laminaria, is a type of brown algae in where the blade is split or branched. Agarum and Alaria the conspicuous rib run along the middle of the single blade. The blade can be long as 25 meter. Commonly known as the sea palm The feather-boa kelp has two branched forms and are common on pacific rocky shores. In the pacific the largest kelps are found in deeper water just below the lowest tide level. The bull kelp, nereocystis consist of whip-like stide up to 30 meter, long with a large spherical pneumatocysts at the upper end Another large kelp is pelagophycus Macrocystis is the giant kelp is the largest of all the kelps and the worlds largest bottom-dwelling organism up to 25 feet or more At the base of each blade a gas-filled pneumatocyst eventually develops, which helps keep the blades close to the surface Kelps are harvested (killed) by chopping off the tops for the extraction of several natural products Kelp beds are among the richest, most productive environments in the marine realm. They show very high primary production, the rate of production of organic matter

Life history

Fragments of the thallus can often grow into new individuals as occurs in the floating masses of sargassum in the Sargasso sea in the Atlantic ocean. Some seaweeds produce spores, which are cells specialized for dispersing to new location or persisting through unfavorable conditions Some spores are protected by resistant cell walls; other have flagella for movements and are known as zoospores The production of gametes is a key event in sexual reproduction. Gametes from two different individuals fuse so that the new generations contain genetic information from both parents. Gametes produced by all members of seaweeds species can be similar in appearance but can consists of non-motile eggs and smaller sperms that can swim by means of flagella. (except the red algae) Male gametes in the red algae lack flagella and are non-motile. They can be released in strands of slime (moist). Males and females gametes can be formed in the same thallus, but the chances are good that fusing gametes will be from separate thalli. Cells of seaweeds divide and produce identical cells by mitosis Seaweeds can also produce haploid spores or gametes via meiosis Their life histories can be divided into two basic types The first basic type - is the most common among all tree groups of seaweeds, involves two types of thalli. The first is a diploid (2n) sporophyte generation that through meiosis produces not gametes but haploid (n) spores. Except in the red algae these spores are typically motile. They divide and develop into the second kind of thallus, a haploid (n) gametophyte generation. The gametophyte is the one that produces haploid gametes. In some species there are separate males (sperm-producing) and gametes (egg producing) thalli; in other, both types of gametes are produced by every thallus. The gametes are released and fertilization produce a diploid (2n) zygote that develops into the diploid sporophyte. A life history with two generations a sporophyte and a gametophyte is an example of the phenomenon of alternation of generation. In some algae such as sea lettuce (ulva) and the brown (dictyota) the sporophyte and gametophyte generally are identical they are called isomorphic On the other hand kelps the large plant we see is the sporophyte whereas the gametophyte is the minute and barely visible thus being polymophic because there are at least two different looking generation Variation of the first type of life history unique to the red algae is more complex involves three generation. The third generation diploid is called carposporophyte. Carpospores, diploid spore produced by the carposporophyte develop into sporophyte. The second type of life history is the easiest to understand is similar to animals. There is not alternation of generation Thus there is only one thallus and it is diploid The thallus produces haploid gametes by meiosis After fertilization the resulting zygote develops into a new diploid thallus This is common in brown algae (fucus and other rockweeds) and in some green algae(codium, halimeda) A variation of this second basic type of life history is that the dominant thallus is haploid and produces haploid gametes. On fertilization the gametes form a diploid zygote. It is in the zygote where meiosis take place resulting in a haploid spore. Each of these spores develops into a haploid individual, the only kind of thallus in the cycle. Reproduction in seaweeds is by asexual and sexual means. Sexual reproduction can involve an alternation of a haploid (gametophyte) and a diploid (sporophyte) generation In some seaweeds the release of male and female gametes take place about the same time

mangrove root adaptations

live in the soft sediments along the shoreline increase stability of mangrove trees in the soft sediments along shorelines. Red mangroves have prop roots descending from the trunk and branches, providing a stable support system. Shallow wide-spreading roots, surrounds the trunks of black mangroves, adding to the structural stability of the tree.

Habitat condition mangrove

1. Tropical Climate Mangroves are tropical species, surviving at temperatures above 66° F (19° C), not tolerating fluctuations exceeding 18° F (10° C) or temperatures below freezing for any length of time. 2. Salty, anoxic soils as halophytes, mangroves are able to live in freshwater and saltwater environments As facultative halophytes, mangroves do not require saltwater to survive. Most mangroves are capable of growing in freshwater habitats, although most do not due to competition from other plants. 3. High sedimentation rate 4. Low wave energy areas 5. Shallow waters 6. Tidal Fluctuations Nutrients are transported into mangrove communities by tides Tides remove wastes from mangrove communities The changing tides, in combination with salinity levels, reduces competition from other plant species. transport the propagules (seedlings) of mangrove trees which increases the distribution of the mangrove trees, while limiting intraspecific (within species) competition for food and space. Intraspecific competition is an interaction in population ecology, whereby members of the same species compete for limited resources.

Reproductive adaption mangrove

2 main reproductive stages: Viviparity and dispersal are reproductive adaptations that give mangroves an increased chance for survival Similar to terrestrial plants, mangroves reproduce by flowering with pollination occurring via wind and insects. Once pollination occurs, the seeds remain attached to the parent tree. They germinate into propagules. Viviparity is an uninterrupted development of an embryo or seedling without a resting phase. The seedling develops into a propagule. Disperal: transport of the propagule by water currents to shallow water where it either take root in the sediments near the parent tree or are dispersed with the tides and currents to other shorelines

Seagrasses

About 60 species exist in temperate and mainly tropical locations. Flowers are small and inconspicuous in most species. Pollen (sperm) is carried by water currents. Tiny seeds produce by fertilization are also carried by water currents or in the feces of animals that consume the seagrasses. Seagrasses are known to exhibit rapid growth and provide food to many organisms They also provide habitat for countless organisms that hide among the blades in seagrass beds (large collections of seagrass plants) Eelgrass is the most widely distributed of the seagrasses where it is widely distributed in shallow water bays and estuaries. Closest relative to seagrasses are lily family, therefore they evolved from land plants Seagrasses have adapted to life in the marine environment They have horizontal stems called rhizomes that commonly grow beneath the sediment. Roots and erect leave grow from the rhizomes The sexual reproduction of seagrasses involved tiny flower. The pollen grain which contain the sperm are produced by male flowers that typically develop in plants that are separate from plants producing female flowers. Some seagrasses produce long, thread-like pollen grain instead of the minute and round pollen of land flowering plants Pollen is often produced in sticky strand and is carried to female glower for fertilization or pollination Water currents are involved in the dispersal of pollen but marine animals such as small crustaceans could also be involved Seagrass flowers might be inconspicuous, because insects are not needed for pollination as in most land plants Seeds and fruits are dispersed by water current and perhaps in the feces of the sea turtle, fishes duck and other animals that graze on the plants Seagrasses readily reproduce asexually by extending rhizomes under the substrate Some seagrasses meadows actually consists of a single gigantic, long-living, genetically identical clone. Most are tropical and subtropical but several species are common in colder water Most seagrasses are restricted to muddy and sandy areas in shallow water but some like surf grass live on rocky shores Different species of seagrasses vary in their maximum depth, but all are limited by the penetration of light though the water. Most species are found in the tropical Pacific and Indian oceans Turtle grass (thalassia) is the most common of seagrass Halophila is paddle grass Amphibolis is strapweed Poisdonia are ribbonweed Extensive meadows are found to depths of about 10 meter Manatee grass is often found together with turtle grass Eelgrass is the most widely distribute of the seagrasses, found in many temperate and tropical regions of the world, where it inhabits shallow well protected coastal water such as bays and estuaries. It has distinctively flat, ribbon-like leaves. It is common in oxygen poor sediments. Like tropical seagrass Thick zostera meadows or beds are highly productive and provide shelter and food to a variety of animals some of considerable economic importance. Mediterranean posidonia meadow, sometimes known as Neptune grass are threatened by pollution and fishing trawls Surf grass is an unusual seagrass because it is an inhabitant of rocky coasts exposed to wave action, as its common name implies. It is found on the pacific coast of north america Seagrass form extensive meadows that have a most important ecological role in shallow-water environments. They provide shelter to a variety of organisms including some of the considerable economic importance, their roots and leaves decrease water turbulence that help stabilize soft bottoms, and are highly productive providing a rich source of detritus that directly or indirectly feed many animals

Salt tolerance adaption

Adaptations for salt exclusion, salt excretion, salt concentration allows mangroves to live where other terrestrial plants cannot

Angiosperm

Angiosperms are true plants. Over 250,000 species exist worldwide, however, only a few of these exist in the marine community. Those plants that do exist there must have mechanisms for dealing with salinity. These plants have true leaves, stems, roots and conducting tissues.

Black Mangrove

Characterized by long horizontal roots and root-like projections known as pneumatophores. The pencil-shaped pneumatophores originate from underground horizontal roots projecting from the soil around the tree's trunk, providing oxygen to the underground and underwater root systems. Grows at elevations slightly higher than the red mangrove where tidal change exposes the roots to air. Heights to 50 feet (15 m). Leaves occur opposite of each other along the branches, with upper sides that are shiny and undersides densely covered with hairs. The bark is dark and scaly. Black mangroves blossom in spring and early summer, producing white flowers.

Red algae

Chlorophyll a, phycobillins (phycocyanin, phycoerythrin) and carotenoids Major food reserve starch Primary producer coralline algae are important source of calcareous deposits in coral reefs ~ 4000 species, almost all marine prefer deep cold waters or warm, shallow waters depending on species Some are coralline (produce calcium carbonate, Ex: Corallina) Mostly marine There are more species of red algae than green and brown They have red accessory pigments called phycobilins which mask chlorophyll Most species appear red though some have difference color depending on their daily exposure This group is essentially marine 10,000 species live in fresh water or soil Most inhabit shallow water marine environments. Some are harvested for food and for the extraction of various products The red algae are the largest group of seaweeds their chlorophyll is typically masked by red accessory pigments Some red have become structure simplified by becoming parasites of other seaweeds A few even have become heterotrophs depending entirely on their host for nutrition Most red algae are filamentous but their thickness vary Dense clumps are more common on the upper levels of rocky shores that are exposed at low tide; longer and flatter branches predominate in areas less exposed to air and in deeper water. These variation are observed among the many species of Gelidium and Gracilaria that found worldwide Endocladia - forms a wiry clumps on rocky shores from Alaska to Souther California Gigartina have large blades as long as 2 meter Porphyra - common on rocky shores above the lowest tide marks from polar to tropical coasts. The most common growth form is a thallus with thin, large blades. Rhodymenia is common in the North Atlantic. Its blades can reach 1 meter in length. Irish moss (chondrus) is another north Atlantic red alga. It can tolerate wide ranges of temperature, salinity and light, and its shape varies greatly in response to these physical factors. The coralline algae are red algae that deposit calcium carbonate within their cell walls. They are important in several marine environments. The calcified thallus takes a variety of shapes, thin disks growing over other seaweeds branches with many joints. Warm-water coralline algae are actively involved in the formation and development of coral reefs

Photosynthetic pigments for seaweeds

Chlorophyll is the essential photosynthetic pigment in all photosynthetic organisms; like unicellular algae, seaweeds and true plants Chlorophyll capture solar energy Types: Chlorophyll a, chlorophyll b and chlorophyll c Chlorophyll a is the primary pigment found in photosynthetic organisms with the exception of some bacteria and archaea. Accessory photosynthetic pigments, such as carotenoids are chemical compounds that also capture solar energy but can only pass it on to chlorophyll a. Therefore carotenoids and chlorophyll a absorb specific wavelength of the visible light spectrum , so by working together it broaden the range of absorption spectrum Chlorophyll a is more efficient in absorbing violet blue and red light not green light, which is reflected and makes chlorophyll appear green. Carotenoids reflects red to yellow portion of the visible light spectrum Chlorophyll b is only found in some groups of seaweeds, is an accessory pigment that absorbs somewhat similar wave length as chlorophyll a Chlorophyll c is an accessory pigment which is mainly found on some unicellular protists as well as brown seaweeds

Salt-March Plants

Cordgrass, Spartina, the predominant salt marsh plant is in the grass family plants border shallow bays and tidal creeks Spartina is only exposed to saltwater at high tide. Spartina is extremely important as habitat to young marine animals such as juvenile invertebrates and fish. Very little Spartina is directly consumed by herbivores. Instead, its importance as a primary producer comes when plants die back in winter and bacteria and fungus break the leaves down to detritus. Detritus is a nutrient source for countless organisms. Spartina plants possess salt glands to help deal with excess salt. Other halophytes (salt-tolerant) Cordgrasses are true members of the grass family. They are not really marine species but rather land plant tolerant of salt Cordgrasses do not tolerate total submergence by seawater. They inhabit salt marshes and other soft bottom coastal areas throughout temperate regions worldwide Cordgrass salt marshes have high primary production and provide habitat and breeding ground for many species important to fisheries. They also offer protection against erosion, the result of the network of horizontal stem that extends under the sediment and provide natural water purification system Flowers and to a much lesser extent leaves, provide food to insects and other grazers. Most organic matter is made available to other organisms in the form of detritus. Cordgrasses inhabit the zone above mudflats that become submerged by seawater only at high tide, so their leaves are always partly exposed to air. Salt glands in the leaves excrete excess salt, other tolerant plants or halophytes such as pickleweed, salt grasses, and rushed can be found at higher levels on the marsh. Rapidly disappearing as victim of coastal development This type of plants are highly significant in the protection against erosion

Red magrove

Grow along the edge of the shoreline where conditions are harshest Tangled, reddish prop roots. These prop roots originate from the trunk with roots growing downward from the branches. Extending three feet (1 m) or more above the surface of the soil, prop roots increase stability of the tree as well as oxygen supply to underground roots. Typically average 20 feet (6 m) in height. Smooth-edged, elliptical leaves have shiny, dark green upper sides and pale green undersides and occur opposite from each other along the branches. Trunks and limbs are covered with gray bark, over a dark red wood. Clusters of white to pale yellow flowers bloom during the spring and early summer months.

Green algae

Major food reserves starch Primary producers; calcareous algae are important sources of calcareous deposits in coral reef Thought to be ancestor of land plants ~ 7000 species; less than 1000 are marine Found worldwide in wet environments Microscopic to macroscopic Some (produce calcium carbonate, Ex: Halimeda) Chlorophylls A and B as well as carotenoids (same as in true plants) Store excess energy as starch (same as in true plants) Cellulose in cell walls (same as in true plants) Live in freshwater and terrestrial environment Around 10% of the more than 7000 species are marine Only 1800 are multicellular Even their low number certain species dominate in environments with variation in salinity such as bays and estuaries and isolated tide pools on rocky coasts. Structurally they have a simple thallus. Photosynthetic pigments and food reserve are the same as those in plants, so its thought that land plants evolved from green algae. Chlorophyll in both green algae and plant is not normally masked by any accessory pigments. Typically have a green bright thallus Multicellular green algae, are common in some marine environment. They are typically bright green because chlorophyll is not masked by other pigments. Filamentous green algae commonly grow on other seaweeds and on rocks in shallow water, including shore tide pools. The filament of these species can be branches or unbranches Enteromorpha - thin thallus in the form of a hollow tube, found in flourish polluted areas Sea lettuce - forms paper-thin sheets whose shape varies depending on the environment Ulva - widespread from polar to tropical water Valonia - forms large sphere or cluster of sphere in the tropics and subtropics Caulerpa- restricted to the tropics and subtropics, consists of thin filament or tubes (siphons) formed from a single giant cell with many nuclei Dead man's finger - is a green alga that extends from tropical to temperate water, including both coasts of North America. It consists of multinucleated filament woven into a spongy, often branching thallus. Thallus of Halimeda consists of calcareous green alga, with deposits of calcium carbonate

Renewal resources mangrove

Mangroves are utilized in many parts of the world as a renewable resource Harvested for durable, water-resistant wood, mangroves have been used in building houses, boats, pilings, and furniture. The wood of the black mangrove and buttonwood trees has also been utilized in the production of charcoal. Tannins and other dyes are extracted from mangrove bark. Leaves have been used in tea, medicine, livestock feed, and as a substitute for tobacco for smoking. In Florida, beekeepers have set up their hives close to mangroves in order to use the nectar in honey production.

red vs black mangrove salinity

Red mangroves occur where soil salinities range from 60-65 parts per thousand (ppt) Black mangroves are found in soils with over 90 ppt salinities. Salinities effectively limit competition from other plants, while mangroves have salt exclusion, salt excretion and salt concentration adaptations allowing survival in these environments.

salt concentration

Salt is moved in old leaves, flowers, bark, or fruit that dies and drops off, being discarded. Ex: White mangroves develop thickened succulent leaves, discarding salt as the leaves eventually drop.

Extra notes

Sea otters help keep the sea urchin population in check too many sea urchins will devour living calper destroying the forest The otter sea urchin diet protects the kelp and helps to maintain diversity and balance in our ecosystem Sunflower stars also prey on sea urchins Kelps provide food and shelter for snails as well as crabs and their tiny crustacean 2011-2012 the animal community was less diverse that It was early in the 1970. For example 13 species of animals in several different groups were missing from historical samples Sargassum animals provide essential food for long distance migrators like sea turtle and bluefin tuna The world oceans are changing. The temperatures and acidity are on the rise and the oxygen is decline

Seaweeds characteristics

Seaweeds are all multicellular; unicellular green and red algae are therefore not considered seaweeds. Seaweeds and unicellular green and red algae are considered protists (Kingdom Protista) Seagrasses, saltmarsh grasses, and mangroves are true plants (Kingdom Plantae) Unicellular algae (red and green algae) and seaweeds are eukaryotic. However, seaweeds cells are more complex than unicellular algae. Though is more complex, seaweeds lack the highly specialized structure and reproductive mechanisms of most terrestrial true plants, especially the flowering plants. Seaweeds multicellular conditions of seaweeds allow many adaption not available to unicellular forms . The ability of seaweeds to grow tall and rise off the bottom provides new opportunities as well as challenges particularly that of wave action Seaweeds are autotrophs, play an important role in coastal environment (they can transform solar energy into chemical energy and make it available to a long list of hungry creatures, which can include humans) Some seaweeds are not producers instead they are parasites of other seaweeds. Seaweed along with unicellular algae produce 90% of the oxygen in the atmosphere, by taking in the carbon dioxide and releasing oxygen. Seaweeds are also called macroalgae While some are thought to be the pre-cursors of plants, algae do not have the same advanced structures seen in plants such as roots, stem and leaves

Seaweed structures

Seaweeds lack true leaves, stems and roots of plants. The complete body of a seaweed is known as thallus, where it is a filament, a thing leafy sheet or a giant kelp. The leaf-like flattened portion of the thallus of many seaweeds are known as blades (They have large surface area and are the main photosynthetic region) In seaweed all portion of the thallus can synthetize as long as it has chlorophyll Blades are not true leaves, because they have no veins or specialized transport tissue. Also, in contrast to true leaves, the upper and lower surfaces of blades are identical to each other. Pneumatocysts are gas-filled bladders that sometimes keep the blade close to the sea surface, thereby maximizing their exposure to sunlight (connect the stipe to the blade) Some sea weeds have a distinct, stem like structure to provide support is known as the stipe. Blades originate from stipe. A structure that looks like root is the holdfast, which main function attach the thallus to the bottom. These are well developed in the kelps (they are not involved in absorption of water and nutrients) Water and nutrients are picked up directly across the surface without the need of roots. Also in contrast to the leaves and stems of plants the stipe and holdfast usually lack tissues specialized for water and nutrient transport Most seaweeds cannot anchor in soft sediments therefore are restricted to hard bottom Seaweeds consists of thallus, which is sometimes provided with leaf-like blades and a root like holdfast. Seaweeds lack true leaves, stems or roots The body of a macroalgae is known as a thallus This thallus can be simple or more advanced in its structure Some algae also possess pneumatocysts, gas-filled bladders used to keep the blades near the water's surface where more light is available for photosynthesis

Mangrove

Seeds of mangroves germinate while still attached to the parent plant and develop into elongated seedlings up to 1 foot in length before falling from the parent tree. About 80 species of mangroves exist only in tropical and subtropical areas . They cannot withstand freezing temperatures. Like Spartina, they only tolerate partial salt water submergence. Mangroves have a thick network of prop roots that are heavily exposed at low tide These seedlings drop into nearby soils or are carried by water currents to new locations Mangrove forests, or mangals, provide habitat for marine organisms such as invertebrates, fish, turtles, birds and marine mammals. They can be though of as the tropical equivalent of salt marshes. Trees and shrubs adapted to live along tropical and subtropical shores around the world They are essentially land plants that can tolerate salt to varying degrees Luxuriant and very productive mangrove forests, or mangals, flourish along muddy or sandy shores protected from wave action There are about 70 mostly unrelated species of flowering plants They are adapted to survive in a salty environment where water loss from leaves is high and sediment are soft and poor in oxygen Adaption becomes more crucial in mangroves living right on the shore such as species of the red mangrove are found throughout the tropics and subtropics Salt marshes replace red mangrove forests in areas exposed to frosts Other important species of mangroves include the black (Avicennia) and white (Laguncularia) mangroves The largest number of species of these and other mangroves are found along the shores of the tropical Indian and Pacific oceans. The world's largest mangrove forest is the Sunderbans, some 10,000 km2 (3,860 mi2) along the coast of Bangladesh and western India. Mangroves are nevertheless abundant in the Atlantic ocean and gulf of Mexico. The leaves of the red mangrove are thick and adaption to reduce water loss Mangroves, seeds germinate while still attached to the parent tree They developed 30 cm before falling from the parent Many species of marine and terrestrial organisms live among the root or branches of mangroves. They also have high primary production but relatively few animal graze on the hard to digest leaves, with most organic matter being consumes as detritus Flowering plants, dominant on lands, have few marine representatives. Seagrasses which are true marine species sand salt tolerant plants like salt-marsh plants and mangroves are exceptions. They have successfully adapted to soft-bottom coastal regions, developing a highly productive meadows and in the case of mangroves, forest along the shore.

Economic importance of seaweeds

Some algae are commercially important as food (ex: think of the algae used in the sushi industry) Other algae are commercially important because of extracts that are harvested from them For example, algin is an extract of brown algae that is used as a emulsifier in dairy products such as ice cream and cheese. Another example is the carrageenan harvested from red algae. Carrageenan is also used as a thickening agent in dairy products such as yogurt, milkshakes, etc. Agar is a second extract from red algae. Agar is used to culture microbes in the health care industry. It is also used as a thickener in foods, used as a filler in pharmaceuticals and cosmetics and to protect canned meats (ever opened a canned ham and noticed the "gel" around it? That's agar.) People harvested seaweeds to be used in many ways. The most common use is the food source. People from different cultures have discovered that many seaweeds are edibles, especially some of the red and brown algae. The farming or aquaculture of seaweed is big business in China, Japan, Korea and other nations Seaweeds produce several type of gelatinous chemicals called phycocolloids, that are used in food processing and in the manufacture of different products. These phycocolloids are valuable because of their ability to form viscous suspension or gels even at low concentration. A phycocolloids called algin is used extensively as a stabilize and emulsifier in the manufacture of dairy produce such as ice cream and cheese, which need to be smooth and not likely to separate. Algin is used in the baking industry to prevent frosting and pies from becoming dry. As a thickener and emulsifier it is used in the pharmaceutical and chemical industries and in the manufacture of various products, from shampoo and shaving cream to plastics and pesticides. Algin also is used in the making of rubber product, paper, paints and cosmetics. Algin is used in the textile industry California is home to extensive giant kelp forests, making this an important algin producing area. A second phycocolloids called carrageenan is obtained from red algae such as irish moss in the north Atlantic and eucheuma in the tropics Carrageenan are farmed in Philippines, and is especially valued as an emulsifier. It is used to give body to dairy products and an amazing variety of processed food, including instant puddings. Another phycocolloids extracted for its ability to form jellies is agar. It is sued to protect ham, fish and meats during canning in low calories food and as a thickener. Biologists use agar as a medium in which to grow bacteria and mold it is also widely used in research involving the analysis of protein and DNA Agar is obtained from several red algae, especially from species of gelidium, gelidiella and pterocladiella Seaweeds can also be used for fertilizers, food additive in animals feeds and wound dressings in hospitals. Coralline algae are sometimes used in Europe to reduce the acidity of soils, and some red seaweeds are marketed as nutritional supplements. Seaweeds are also being investigated as a source of biofuels

Flowering plants

The approximately 350,000 species of flowering plants, or angiosperms are the dominant plants on lands, but a few do live in the ocean. Like other land plants (fern, coniferns and nonflowering plants) and in sharp contrast to algae are protists. Flowering plants have true leaves, stems and roots They all include specialized tissue to transport water, nutrients and the food manufactured by photosynthesis. As such they are grouped in the kingdom plantae Seagrasses are truly marine, most of the time they live submerged by seawater rarely exposed at low tide. Salt-marsh grasses and mangroves inhabit estuaries and shores protected from wave action, they are not completely at home in the ocean and usually only their roots are covered by water at high tide. Reproduction in flowering involves alternation of generation a dominant sporophyte and minute gametophyte The gametophyte develop in the sporophyte flower and are thus dependent on the sporophyte. The male gametophyte produced haploid male gametes is contained within the pollen grain The female gametophyte is the embryo sac, which produced the haploid egg cells. Both gametophyte develops either within a single flower or in separate male and female flower

Types of seaweeds

The classification of seaweeds depends not only structure but also the type of photosynthetic pigments and the food product they store. There are three types of seaweeds: Green, brown and red algae. Its not always easy to recognize them by their color because it depends on the water depth and age.

primary production

The conversion of carbon from an inorganic form, carbon dioxide, into organic matter by autotrophs—that is, the production of food

What is most familiar type of marine algae?

The most familiar type of marine algae are those popularly known as seaweeds. "Algae" and "seaweeds" are interchangeably except that all unicellular "algae" are not "seaweeds" but all "seaweeds" are "algae" (Remember that red seaweeds and red algae means the same)

Anaerobic Sediment adaptions mangroves

specialized root structures allow mangroves to live in oxygen-poor sediments In soils that are not waterlogged, air diffusion between sediment grains can supply this requirement. However, in waterlogged soils, these spaces fill with water containing lower oxygen levels than air. mangroves have poorly developed, shallow below-ground root systems while having well-developed aerial roots. These aerial roots allow for the transport of atmospheric gases to the underground roots. Red mangroves have prop roots extending from the trunk and adventitious roots from the branches (upper right). Black mangroves have pneumatophores, extend upward from the underground roots above the soil surface. During low tides, air is taken up through open passages in the pneumatophores and transported to living root tissues (lower right).

Animals that swim through a mangrove forest

sponges (porifera) oysters (mollusca) sea anemones (cnidaria) barnacles (arthropods) sea squirts (tunicates) shrimp (arthropods) spiny lobsters (arthropods) fishes crabs (arthropods)

Salt exclusion

the ability to exclude salts occurs through filtration at the surface of the root. Root membranes prevent salt from entering while allowing the water to pass through. This is effective at removing the majority of salt from seawater. Ex: red mangrove

Most marine photosynthetic organisms are not considered true plants at all and therefore are not members of the kingdom Plantae? true or false

true