CHAPTER 11 The Eukar yotes^177
BLOOD AND TISSUE PROTOZOA
Hemoflagellates are protozoa that are carried by blood-feeding insects and are
transmitted into the blood stream by the insect’s bite. Here are commonly found
hemoflagellates:
- Trypanosoma gambiense: T. gambienseis transmitted in the saliva of the
tsetse fly as a result of a bite and causes trypanosomiasis, which is better
known as African sleeping sickness. - Trypanosoma cruzi: T. cruziis carried by the Reduviid bug or “kissing
bug,” which is commonly called the kissing bug because it bites the face. T.
cruzicauses Chagas’ disease.Chagas’ disease is thought to have made
Charles Darwin sick during his voyage on the H.M.S. Beagle.Typically
there aren’t any symptoms for months after the bite. During this time T.
cruzi spreads through organs of the body, weakening the heart, intestines,
and esophageal. It also cause, both eyes to swell (Romaña’s sign).
CILIATES
Ciliates(Fig. 11-3) are protozoa that have shorter hair-like structures called
cilia that are found in rows on the outer surface of the cell. These cilia are used
to move the protozoa through the environment and are used to bring food into
the cell.
An example of a ciliate is Balantidium coli. It is the only ciliate that causes
disease in humans. When ingested, it enters the large intestine, causing severe
dysentery.
Fig. 11-3. Ciliates are protozoa that have cilia.