ALGAE

ALGAE

Simple rootless plants that grow in sunlight waters in proportion to the amount of available nutrients. They can affect water quality adversely by lowering the dissolved oxygen in the water. They are food for fish and small aquatic animals.
Algae are Photosynthetic, almost exclusively aquatic, nonvascular plants that range in size from simple unicellular forms to giant kelps several feet long.

CLASIFICATION OF ALGAE:

There are seven types of algae.

1. BACILLARIOPHYTA (diatoms)
2. CHAROPHYTA (stoneworts)
3. CHLOROPHYTA (green algae)
4. CHRYSOPHYTA (golden algae)
5. DINOPHYTA (dinoflagellates)
6. PHAEOPHYTA (brown algae)
7. EUGLENOPHYTA.

1.      BACILLARIOPHYTA (diatoms)

Bacillariophyta are unicellular organisms that are important components of phytoplankton as primary sources of food for zooplankton in both marine and freshwater habitats. Most diatoms are planktonic, but some are bottom dwellers or grow on other algae or plants. 

2.      CHAROPHYTA (stoneworts)

Charophyta are freshwater plants and generally grow anchored to the substratum by rhizoids with a shoot extending upward, Covers the bottom of the ponds. Their green color comes from chlorphylls.

3.      CHLOROPHYTA (green algae)

Most chlorophytes are aquatic, but some green algae can live on the surface of snow, on tree trunks, in soils, or symbiotically with protozoans, The typical color of plants in the Chlorophyta, resulting from the dominant chlorophyll pigments, is some shade of apple or grass green, although certain species may appear yellow-green or blackish-green due to the presence of carotenoid pigments or high concentrations of chlorophyll. 

4.      CHRYSOPHYTA (golden algae)

Chrysophytes are photosynthetic, unicellular organisms that are abundant in freshwater and marine environments. Chrysophytes contain chlorophyll, which are masked by the accessory pigment fucoxanthin, a carotenoid. In many ways, golden algae are, biochemically and structurally similar to brown algae.

5.      DINOPHYTA (dinoflagellates)

The division Pyrrophyta (from the Greek "pyrrhos" meaning flame-colored) The name "dinoflagellate" refers to the forward- spiraling swimming motion of these organisms. They are free-swimming protists (unicellular eukaryotic microorganisms) with two flagella, a nucleus with condensed chromosomes, chloroplasts, mitochondria, and Golgi bodies. Biochemically, photosynthetic species possess green pigments, chlorophyll.

6.      PHAEOPHYTA (brown algae)

The Phaeophyta are almost entirely marine, frequently dominating rocky shores in cold and temperate waters throughout the world. he large kelps are harvested for use as an emulsion stabilizer, in products such as ice cream. They are also used as fertilizer and as a vitamin rich food source.

7.      EUGLENOPHYTA: (euglena)

Have chlorophyll and carotenoid pigments for photosynthesis and flagella for movement, they share characteristics with both plant and animal.

CHARACTERISTICS OF ALGAE:

1.      They are primarily photoautotrophs.

2.      Most have cell wall, which contains silicon carbonate or silica, is a protein.

3.      Most live in water, others on rocks, plants and animals.

4.      The color varies, there are green (charophytes, chlorophylls), red, yellow, brown. Latest Three, his color must accessory pigments in which give such property in order Algae sunlight catch depths.

5.      To be classified as:  Unicellular and multicellular.

6.      They have accessory pigments: phycobilin, xanthophyll, carotene.

7.      Possesses Chlorophyll: A, B, C, D, E for photosynthesis.

8.      All have plant reserves (stored energy produced by the splitting of some organelles (ATP). These reserve substances are:

·         Starch.

·         Glucose.

9.      The movement is thanks to the flagella, these are formed by microtubules.

10.  Photoautotrophic and carry on photosynthesis.

11.  Some forms, however, are chemo heterotrophic and obtain energy from chemical reactions and nutrients from preformed organic matter.

12.   Most species are saprobes.

13.  Some species are parasites.

14.  Reproduction in algae occurs in both asexual and sexual forms.

15.  Range in size from microscopic to single celled organisms to large seaweed.

REPRODUCTION:

Algae reproduce by both sexually and asexually.

ASEXUAL REPRODUCTION: In asexual reproduction an individual reproduce without combining its genetic material with that from another individual.

Types of asexual reproduction:

Ø  BINNARY FISSION: Unicellular organism simply divides into two new individuals.

Ø  FRAGMENTATION: In which fragment of the parent develop into a new individual.

Ø  BUDDING: Buds detach from multicellular algae and develop into new individual.

Ø  SPORES: Algae produce spores that are capable of growing into new individual.

SEXUAL REPRODUCTION: In sexual reproduction genetic material from two individual is combined.

Types of sexual reproduction:

Ø  CONJUGATION: Two similar organism fuses, exchange material and then break apart.

Ø  ZYGOTE: Algae involving the union of gaments, to form a single cell.

USES OF ALGAE:

Ø  Fertilizer: Algae are used by humans in many ways. They are used as fertilizers, soil conditioners and are a source of livestock feed.

Ø  Energy source: Algae can be used to make biodiesel (see algaculture), bioethanol and biobutanol and by some estimates can produce vastly superior amounts of vegetable oil, compared to terrestrial crops grown for the same purpose. 

•         Algae can be grown to produce hydrogen.

•         Algae can be grown to produce biomass, which can be burned to produce heat and electricity.

Ø  Pollution control: Algae are used in wastewater treatment facilities, reducing the need for greater amounts of toxic chemicals than are already used.

Ø  Stabilizing substances: It is an excellent stabilizer in milk products - it reacts with the milk protein casein, other products include: pet foods, toothpaste, ice-creams and lotions etc.  Alginates in creams and lotions are absorbable through the skin.

Ø  Nutrition: Seaweeds are an important source of food, especially in Asia; They are excellent sources of many vitamins including: A, B1, B2, B6, niacin and C. They are rich in iodine, potassium, iron, magnesium and calcium. 

Ø  The natural pigments produced by algae can be used as an alternative to chemical dyes and coloring agents.

Ø  Many of the paper products used today are not recyclable because of the chemical inks that they use, paper recyclers have found that inks made from algae are much easier to break down.

Ø  There is also much interest in the food industry into replacing the coloring agents that are currently used with coloring derived from algal pigments.

Ø  Algae can be used to make pharmaceuticals.

Ø  Sewage can be treated with algae as well.

Ø  Some Cosmetics can come from microalgae as well.