Page 74 - Biology - XII

SPOT - 2

Psedopodium
Food vacuoles Red blood cells being digested Bacteria

Endoplasm Karyosome

(a) Entamoeba histolytica (b) Entamoeba gingivalis (c) Entamoeba coli

Fig. 13.2: Trophozoites of: (a) Entamoeba histolytica, (b) Entamoeba gingivalis, and (c) Entamoeba coli

A. Comments
1. It is the slide of (Entamoeba histolytica), a protozoan which is endoparasite of human intestine.
2. Most of the people and children get infected by this parasite due to improper sanitation, hygiene,
and eating of raw unwasted/uncooked vegetables.
3. The infection of this parasite leads to amoebic dysentery.
The symptoms of this disease are—
(a) The patients discharge mucous and blood in their stools only in severe cases.

(b) ‘Recurrent diarrhoea’ accompanied with abdominal pain, headache, nausea, weakness, narrowness,
etc.
(c) Sometimes it causes intermittent colic pain.
Systematic position
Phylum – Protozoa Class – Rhizopoda Type – Entamoeba histolytica

B. Comments
1. It is the slide of (Entamoeba gingivalis), a protozoan which is endoparasite found in tartar and
debris around the teeth or abscess of gums, pus pockets of tonsils of humans, and other animals
(dog, cat, etc.).
2. Over 60% of human population is infected by this endoparasite.
3. Over 90% of people suff ering from pyorrhoea harbour this parasite, therefore, it is considered to
cause pyorrhoea.
The symptoms of the disease are —
(a) foul/bad smell from mouth (c) damaged gums, teeth
(b) discharge of pus

C. Comments
1. It is the slide of Entamoeba coli, a protozoan which is a commensal parasite in human colon.
2. Over 50% of human population is infected by it.
3. In general it is neither harmful nor benefi cial to human as a parasite. Hence, it is a commensal
parasite.

4. However, in certain cases symptoms of diarrhoea may be observed.

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