To observe the disease-causing organisms like Ascaris, Entamoeba, Plasmodium and Ringworm through permanent slides.
Preserved slides or specimens of disease-causing organisms like Ascaris, Entamoeba, Plasmodium and Ringworm.
Observe the specimens or slides and identify the organism on the basis of its features.
Type: Ascaris lumbricoides
Ascaris exhibits the following characteristic features:
- It has a long, cylindrical and unsegmented body.
- The male and female organisms are separate.
- It bears a mouth at the anterior end surrounded by three lips.
- There is an excretory pore on the ventral surface slightly behind the anterior end.
- A pair of penial spicules are present in the male worms close to the cloacal opening.
- The female genitals are present at about one-third distance from the anterior end.
Ascariasis is the disease caused by Ascaris lumbricoides or roundworm.
- Abdominal cramping
- Abdominal swelling
Type: Entamoeba hystolytica
Following are the characteristic features of Entamoeba:
- It is a unicellular organism with an irregular shape.
- It consists of a few food vacuoles. The contractile vacuole is absent.
- Cysts with four nuclei are present.
- It consists of a nucleus located eccentrically in the cell.
Entamoeba histolytica is an organism found in the intestines of humans that is responsible for causing amoebic dysentery.
- Abdominal pain
- Watery diarrhoea with mucus, blood and pus
Type: Plasmodium vivax
Plasmodium can be identified by the following characteristic features:
- It is a unicellular endoparasite found within the red blood cells of the diseased person.
- The parasite is mostly diagnosed at the “signet ring” stage where the parasite appears as a round body.
- There is a big vacuole present inside the cell. The cytoplasm is accumulated at one place and contains the nucleus.
Plasmodium vivax is a protozoan parasite that causes malaria in humans. The infected female anopheles bites a healthy person and transmits the sporozoite into the peripheral blood vessels of humans, thereby, causing malaria.
- High fever
- Shaking chills from moderate to severe.
Type: Trichophyton rubrum
Trichophyton or ringworm fungus has the following characteristic features:
- This fungus feeds on the keratin of the skin of human beings.
- The hyphae are waxy and can be smooth or cotton-like.
- Hyphae that are not stained are yellowish-brown, reddish-brown or white in colour.
Ringworm is a communicable fungal infection of the skin.
- Scaly, itchy skin
- Red and raised patches
- They are redder at the periphery than at the centre and forms a ring-like appearance.
Also Read: Microbes and Disease
For any information on Biology experiments CBSE Class 12, keep visiting BYJU’S website or download BYJU’S app for further reference.