1.
Algae

2.
Submitted To:
Submitted By:
Department :
Roll No :
Zoology (GPCSF)
am. Naghma Shehzadi
Ahmad Raza
151835
Course code :301
Course Title : Diversity of Plants(Botany)

3.
Aquatic Algae:
They are found in ponds, lakes, ditches, streams, running water and oceans (volvox,chara).

4.
Terrestrial Algae:
They are found growing on moist shady
soil or rocks (Vaucheria and Nostoc).

5.
Cryophytes:
They are found in mountain peaks
covered with snow. They impart color to
mountains(Chlamydomonas).

6.
Aerophytes:
They are adopted for aerial mode of life
and occur in tree trunk and moist soil.

7.
Thermophytes:
These algae occurs in hot springs. They
can tolerate upto 85℃(Haplosiphon).

8.
Zoospores:
They are motile spores. They are spherical in certain cases they are kindney shaped.

9.
Aplanospores:
They are non-motile spores. These are that zoospores that failed
to develop flagella(Vaucheria).

10.
Exsospores:
Cell wall ruptures at distal end and spores are cut off from
the exposed protoplast.

11.
Endospores
In some cases the protoplast divides to form spherical units
which secrete new wall these are called endospores.

12.
Tetraspores:
Four non-motile spores per sporangium in members of Phycophyta.
Monospores:
A single non.motile Batrachospermum.

13.
Akinetes:
In memranes of Cyanophyta and Chlorophyta, the vegetative cell round off and the
Original parent
wall becomes extremely thick to form akinetes.

14.
Hypospores:
In certain algae, e.g., Chlamydomonas aplanospores secrete
thick wall to become hypo spore.

15.
The algae exhibit a wide variety of thallus organization.The
range of thallus organization is from
unicells,colonial,filamentous and heterotrichous plant body

16.
Structure of Algae Cell
The algal thalli are formed of two types of cells.
i.Prokaryotic Cell ii.Eukaryotic Cell

17.
>Fusion of two haploid cells.
>Deploid zygot.
>Gametes involved might be isogemetes or hetrogemetes.
>Smaller or active gemetes (male gametes )
>larger or passive gametes ( female gametes)

18.
Isogamous Sexual Reproduction
If two gametes similar and size and structure fuse to form the zygote it is called isogamy
and the sexual reproduction is known as isogamous sexual reproduction.
Heterogamous Sexual Reproduction
If two gametes dissimilar in size and structure fuse to form zygote it is called heterogamy
and the sexual reproduction is known as heterogamous sexual reproduction. it have two types
(i) Anisogamy (ii) Oogamy

19.
Economic Importance
Some of the economic importance are given below;
> Mentioned in Chinese poetic literature about 600 B.C.
Beneficial Aspect of Algae
Role as a primary producers:
They provides food and energy to equatic life.They produce oxygen and release carbon dioxide.
Source of Food:
They are the main source of food. More than 100 species belonging to green-,brown-. Red-algae for humans
because of presence of proteins (Monostorma, Ulva, Codium and Chlorella).
Brown algae having the highest value of food production.
Fucus and Ascophyllum ar usd as fooder for animals/
Industrial Use:
They are videly used in industrial level. As…….
Agar-Agar
Gelling agent from seaweed: a powdered seaweed extract. Use: gelling agent, thickener.

20.
Algae as fodder for cattle:
Rhodymenia palmata is used as food for sheep in Narvey. Laminaria saccharina, Pelvitia, Ascophyllum, etc.
species are used as food for cattle.
Algae as fertilizers:
Blue-green algae are treated as bio-fertilizers from olden days. Nostoc, Oscillatoria, Scytonema, Spirulina,
etc. are used as fertilizers to rice fields. All these algae fix the atmospheric nitrogen. Cultivation of Spirulina is
gaining importance as feed for fish, poultry and cattle.
Algae in Pisi culture:
Sea algae are used as food for fishes. So they play an important role in Pisi culture. Some green-algae,
diatoms, some blue-green algae are used as food material to fishes. These are also making the water clean, by
realizing Oxygen.
Algae in reclamation of alkaline or usar soils:
Our country has more number of alkaline soils or sterile soils. Blue-green algae like Nostoc, Oscillatoria,
Scytonema, Spirulina are used to modify these soils in to fertile soils. Because they fixed nitrogen in to soil.
Nearly they fixed 400kg. of nitrogen per year. Soil erosion is also reduced by these algae.

21.
Algae in industry
Iodine industry is mainly depended upon algae. Algae belonging to Phaeophyceae, like Laminaria,
Ecklonia, Eisenia, etc. are used in the industry to prepare iodine. Phyllophora is used to prepare iodine in
Russia.
Antibiotics
Antibiotic Chlorellin, obtained from Chlorella is effective against a number of pathogenic bacteria. Extracts
from Cladophora, Lyngbya can kill pathogenic Pseudomonas and Mycobacterium. Laminaria is used as
one of the modern tools for abortion. Seaweeds have beneficial effect on gall bladders, pancreas, kidneys,
uterus and thyroid glands.
Role of algae in sewage disposal
Some species like Chlamydomonas, Scenedesmus, Chlorella, Pondorhina, Euridina, etc. are living in
sewage water. They are mainly useful to clean the water by releasing oxygen. They also modify the
carbonate material in the water into N, P, K fertilizers.