Algae are diverse photosynthetic organisms ranging from unicellular to multicellular forms, thriving in aquatic environments. They play a crucial role as primary producers, contributing to oxygen production and reducing water pollution, while also having various industrial and medicinal uses. Different types of algae, including green, brown, and red algae, possess unique characteristics and applications in food, fertilizers, and medicine.

1. ALGAE

2. ALGAE
are photosynthetic organisms that
occur in most habitats. They vary
from small, single-celled forms to
complex multicellular forms, such as
the giant kelps that grow to 65
meters in length.
are very simple chlorophyll-
containing organisms.

3. CHARACTERISRICS
Unicellular or multicellular.
Cells are covered with rigid cellulose
cell wall.
Absence of conducting vessels and
mechanical tissues: entirely formed
with parenchyma cells.
Reproduction occurs by vegetative,
asexual and sexual reproduction

4. All algal cells are aquatic. They can
inhabit fresh or salt water, as well
as every salinity level in between.
They are THALLUS - they lack true
roots, stems, and leaves, fruits,
connecting tissue etc. and
photosynthesis occurs throughout
the plant, not just the leaves.
CHARACTERISRICS

5. STRUCTURE OF
ALGAE

6. HOLDFAST
a specialized
structure on the
base of an algae
which acts as an
“anchor” allowing
it to attach to a
surface (e.g. a
rock).

7. stipe is a stalk
that supports
some other
structure.
is like the stem
of a flower
STIPE
STIPE

8. A leaf like
structure that
contains
photosynthetic
materials.
BLADE
BLADE

9. Pneumatocysts,
or air bladders,
are gas-filled
sacs in an algae
that float the
algae's blades up
toward the
water's surface.
AIR BLADDERS

10. GREEN ALGAE

11. This is the most diverse group of
algae, with over 7,000 species.
The organisms are largely aquatic
or marine.
Cells of the Chlorophyta contain
organelles called chloroplasts in
which photosynthesis occurs
CHLOROPHYTA

12. EXAMPLES OF
CHLOROPHYTES
SEA LETTUCE UMBRELLA ALGA

13. EXAMPLES OF
CHLOROPHYTES
TUFTED JOINT
ALGA
UDOTEA

14. is a division of freshwater green
algae.
Charophyta are commonly known as
stoneworts or brittleworts.
derived from two Greek roots that
mean joy (khara) and plant (phyto)
It was commonly believed that
Charophyta were related to
embryophytes (land plants)
CHAROPHYTA

15. They grow completely submerged in the
water of wetlands, rivers, streams,
lakes, estuaries and swamps, in fact, all
sorts of non-marine watery habitats.
are useful components of aquatic
ecosystems. Many species require high
water quality and clarity for survival, so
their presence can indicate the
existence of a healthy ecosystem.
CHAROPHYTA

16. EXAMPLES OF
CHAROPHYTES
MESOSTIGMA CHARA

17. EXAMPLES OF
CHAROPHYTES
COSMARIUM CHLOROKYBUS

18. BROWN ALGAE

19. consisting of those organisms
commonly called brown algae.
almost entirely marine, frequently
dominating rocky shores in cold
and temperate waters throughout
the world.
PHAEOPHYTA

20. about 265 genera with about 2000
species.
Contains pigments Chlorophyll a
and c; and Fucoxanthin
PHAEOPHYTA

21. EXAMPLES OF
PHAEOPHYTES
LAMINARIA WIREWEED

22. RED ALGAE

23. are a moderately diverse, but
extremely ancient, group of
marine organisms
About 500 genera, with about
5000 species
red because of the presence of
the pigment phycobilin.
RHODOPHYTA

24. Have high vitamin and protein
content .
Mostly marine organisms.
It is believed that Rhodophyta
were among the first multicellular
organisms.
RHODOPHYTA

25. EXAMPLES OF
RHODOPHYTES
DELESSERIA CORALLINE ALGAE

26. GOLDEN ALGAE

27. are common microscopic chromists
(colored organisms) in fresh water.
Some species are colorless, but
the vast majority are
photosynthetic.
contain chlorophylls a and c, which
are masked by the accessory
pigment fucoxanthin.
CHRYSOPHYTA

28. In many chrysophytes the cell
walls are composed of cellulose
with large quantities of silica.
Some have one or two flagella,
which can be similar or dissimilar.
A few species are amoeboid forms
with no cell walls.
CHRYSOPHYTA

29. EXAMPLES OF
CHRYSOPYTHES
STRIATELLA FRAGILARIA

30. IMPORTANCE

31. Primary producers
- Algae are the main Oxygen
producers in aquatic areas. They
are also useful in decreasing water
pollution by releasing Oxygen.
GENERAL USES

32. Algae as food
They served as food for marine and
terrestrial animals as well as human.
GENERAL USES

33. Algae as fertilizers
Some algae contain significant
amount of P,K,N and other micro
and macro elements which are
essential for plant growth.
GENERAL USES

34. Iodine production
Iodine industry mainly depends on
algae
INDUSTRIAL USES

35. Alginates
as an excellent functionality as a
thickening agent, gelling agent,
emulsifier, stabilizer, texture-
improver (for noodles), to improve
the quality of food.
Alginate is used for the production
of welding rod, as a binder of flux.
INDUSTRIAL USES

36. Alginates
Alginate is used in cosmetics area
with several applications with its
functionality of thickener and
moisture retainer. Alginate helps
retaining the color of lipstick on lip
surface by forming gel-network.
INDUSTRIAL USES

37. Carrageenan
Used for textile, leather and tire
production
used in the food industry, for their
gelling, thickening, and stabilizing
properties.
INDUSTRIAL USES

38. Brown algae mainly used in
manufacture of various goiter
medicines due to their high
iodine content.
MEDICINAL USES

39. Some algae, like Gelidium are
used for treatment of kidney,
bladder and lung diseases while
Laminaria is used as surgical tool
in the opening of wound due to
its gentle swelling property.
MEDICINAL USES