Algae and the Origin of Eukaryotic Cell
Protozoans and algae
Embryophytes
Endosymbiosis
Two organisms lived together one inside the other and both benefited
Living descendants of clades that originated from those early steps in eukaryote evolution
This line give rise to algae including green algae which in turn produced true plants
Origin of eukaryotic cells
DNA structure
Nuclear structure and division
Organelles
Origin of Mitochondria and plastids
Origin of mitochondria
origin of plastids
Characteristics of various groups of algae
Green Algae
Brown Algae
Yellow green algae
Diatoms
Golden Brown algae
Oomycetes
Euglenoids
Swim actively with two flagella located at the cells anterior end one short and the other quite long
Diverse in structure and nutrition
Each cell has a wall composed of two halves or frustules that fit together like a petri dish and its lid
Single celled covered with numerous tiny siliceous scales that develop within special vesicles in the endoplasmic reticulum
Occurs mostly in fresh water and formerly many were thought to be green algae until chlorophyll c was discovered in them.
They are resilient and survive many types of disturbances and changes
Almost exclusively marine only a few fresh water
Red Algae
Constitute large group of especially distinct and fascinating algae
Body construction of green algae
Nonmotile Colonies
Filamentous body
Motile colonies
Membranous Body
Parenchymatous body
Siphonous body
Genera of green Algae
Motile Colonial Species
Filamentous Species
Unicellular Species
Laminar species
Coenocytic species
Parenchymatous species
If cell adhere loosely the resulting structure is a Colony
Occurs if the cells lose their flagella or never develop them
Results if cells are held tightly by a middle lamella
Results if the orientation of cell division is controlled precisely
Results if karyokinesis occurs without cytokinesis and giant multinucleate cells result
Results if cell division occurs regularly in all three planes