5. “Algae is a term that describes a large and incredibly diverse group of eukaryotic,
photosynthetic lifeforms. These organisms do not share a common ancestor and hence,
are not related to each other (polyphyletic).”
6. Algae exist in environments ranging from oceans, rivers, and lakes to
ponds, brackish waters and even snow. Algae are usually green, but
they can be found in a variety of different colours.Multicellular
examples of algae include the giant kelp and brown algae. Unicellular
examples include diatoms, Euglenophyta and Dinoflagellates.Most
algae require a moist or watery environment; hence, they are ubiquitous
near or inside water bodies. Anatomically, they are similar to another
major group of photosynthetic organisms – the land plants.
7. GENERAL
CHARACTER OF
ALGAE
Algae are photosynthetic organisms
Algae can be either unicellular or
multicellular organisms
Algae lack a well-defined body, so,
structures like roots, stems or
leaves are absent
Algaes are found where there is
adequate moisture.
Reproduction in algae occurs in
both asexual and sexual forms.
Asexual reproduction occurs by
spore formation.
Algae are free-living, although some
can form a symbiotic relationship
with other organisms
8. TYPES OF ALGAE
There are three main types of algae,
Green Algae (Chlorophyta)
Brown Algae (Phaeophyta)
Red Algae (Rhodophyta)
9. Green Algae
(Chlorophyta) •
•
•
•
•
Green Algae (Chlorophyta)
Green algae can be f ound in salt water, f resh water, and
sometimes even on moist land. They convert sunlight into starch
and save it in their cells to consume as their f ood. Their coloration
comes f rom high amounts of chlorophyll A and B in them. I t is also
said that green algae might be the progenitors of plants.
Green Algae Uses
Along with being rich in antioxidants and minerals, it also has
antibacterial and antiviral characteristics making it a highly used
mineral in the medical industry. Cosmetics and f ood industries also
use it extensively. Green algae benefits include its ability to purif y
the air by absorbing carbon dioxide f rom the atmosphere and
releasing oxygen.
Green algae need carbon dioxide to grow. I n return, they produce
oxygen helping in clearing the CO2 emissions f rom dif ferent energy
sources. Utilizing this characteristic, The aerium was invented to
purif y your indoor surroundings organically.
10. Brown Algae
(Phaeophyta)
•
•
•
Brown alga is the most complex of the three types. It
contains a pigment called Fucoxanthin which is not
found in red and green algae. These yellowish-brown
elements are often rooted from stationary structures
like docks, shells, or rocks by their ‘holdfasts’ which are
root-like parts attached to them.
Brown Algae Uses
Besides being a nutritious food source for humans and
herbivorous organisms, brown algae have commercial
uses. They are used in the production of alginates,
which are used in industrial manufacturing and
employed as food additives, food fillers, and food
thickeners. They are also used as stabilizers in the
battery ionization process.
11. Red Algae
(Rhodophyta)
•
•
•
Red algae or Rhodophyta are the oldest types of algae
found in both marine and freshwater lakes. They like to
grow on solid surfaces independently and sometimes
attach themselves to other algae. Their cell walls
contain cellulose and many different types of
carbohydrates.
Red Algae Uses
Red algae are rich in calcium, magnesium, vitamins,
minerals, and antioxidants. Agar, which is a substance
extracted from red algae, is used as a dairy topping.
Red algae are also a source of dietary fibers which
promote blood circulation and regulate blood sugar
levels.
13. The most comprehensive and authorative
classification of algae was given by F.E
Fritsch (1935) in his book ‘The Structure
and Reproduction of the Algae’.
His classification was based on such
criteria as pigmentation, types of flagella,
assimilatory products, thallus structure
and methods of reproduction.
14.
F.E. Fritsch (1935, 1948) divided algae
into 11 classes on following basis:
Number and mode of attachment
No of flagella in the motile cells
Thallus structure
Chemical nature of pigments
Reserve food materials
Method of reproduction
Variation in the life cycles
17. O ne of t he m os t i m por t ant l i vi ng or gani s m s i n t he aquat i c
e c os ys t e m ar e phyt opl ank t on. Phyt opl ank t on ar e m i c r os c opi c al gae t hat
oc c ur i n uni c e l l ul ar, c ol oni al , or fil am e nt ous f or m s . Phyt opl ank t on
abundanc e i n a wat e r body r e fle c t s t he ave rage e c ol ogi c al c ondi t i on
and, t he r e f or e , i t m ay be us e d as an i ndi c at or of wat e r qual i t y. T hey ar e
an e xc e l l e nt e c ol ogi c al i ndi c at or at t he s pe c i e s l eve l , s e ns i t i ve t o a
num be r of e nvi r onm e nt al var i abl e s i nc l udi ng l i ght , t e m pe rat ur e ,
i nor gani c nut r i e nt s ( c ar bon, phos phor us , ni t r oge n, s i l i c a, and i r on) ,
or gani c c ar bon, or gani c ni t r oge n, oxyge n c onc e nt rat i ons , pH and
s al i ni t y.
It was al s o c onc l ude d t hat al gae ar e gr e at l y adapt i ve or gani s m s and m ay s ur vi ve i n di f fe r e nt e nvi r onm e nt al
c ondi t i ons , wi t h c hangi ng di ve r s i t y, t e m pe rat ur e and bi ol ogi c al c om m uni t i e s .
