Zoochlorella
and
Zooxanthellae
- These
are
the
endosymbionts
of
protozoa.
The
green
algae
are
present
in
freshwater
forms
of
Ciliophora
and
Rhizopoda,
whereas
in
marine
forms
there
are
generally
yellow
or
brown
algae.
The
two
types
of
algae
are
called
zoochlorellae
and
zooxanthellae
respectively.
Each
protozoan
cell
harbors
from
50
to
several
hundred
algae.
The
algae
resist
digestion
by
the
host.
Alga
converts
CO2
to
organic
products
through
photosynthesis,
liberating O2
.The
animal
uses
02
for
respiration
and
produces
CO2
as
by
product.
