بسم الله الرحمن الرحيم Algae Lab 8

Algae : are alarge and diverse group of Photosynthetic, eukaryotic, plant-like organisms that use chlorophyll in capturing light energy.but lack characteristic plant structures such as leaves, roots, flowers, vascular tissue, and seeds.

General characteristics and ecology Algae can be unicellular as well as multicellular,large and complex forms found in the ocean called seaweed. Algae are usually found in damp places.most unicellular and colonial algae are aquatic, and float near the surface of the water.

The seaweeds grow mostly in shallow marine water, but some,such as the red algae, can grow quite deep in the ocean.

Reproduction Asexual Reproduction : Ex: binary fission….. formation of spores Sexual Reproduction : Ex: Isogamy…….. Heterogamy

Euglena -Spindle-shaped. -No cell wall, thus changes shape as it moves. -Pair of flagella -Contains red eyespot.

Euglena gracilis reservoir pigment spot contractile vacuole flagellum chloroplast pyrenoid nucleus 65µ cell membrane

Chlamydomonas -Common inhabitant of freshwater pools. -Pair of flagella. -Single, cup-shaped chloroplast.

Chlamydomonas flagellum contractile vacuoles Pigment spot nucleus pyrenoid chloroplast cell wall cytoplasm

Volvox A colony consists of cells with flagella

Spirogyra Common freshwater algae consisting of unbranched filaments of cylindrical cells.

cell wall cytoplasm chloroplast nucleusvacuole Single cell of spirogyra strand of cytoplasm chloroplast nucleus cell wall strand of cytoplasm. 3D representation of spirogyra cell structure

Diatoms Mostly unicellular in both fresh and salt water.