- Bilaterally symmetrical, triploblastic, unsegmented cylindrical true worms with pseudocoel (i.e. pseudo coelomates)
- Presence of sensory papillae.
- Amphid; in mouth
- Phasmid; in anus
- Alimentary canal of roundworm is straight and have both anus and mouth
- Amphids = olfactory receptors
- Phasmid = chemo-receptors and glandulo-receptors
- Excretory organs are protonephridia / renette cells / giant cells
- Larval forms; Rhabditiforms, Filariforms, Microfilaria
- 1ST UNISEXUAL PHYLUM
- SEXUAL DIMORPHISM IS PRESENT
DIVIDED INTO 5 CLASSES;
1.CLASS; Nematoda
- Commonly called roundworm
- Body wall; syncytial cuticle
- Divided into 2 groups;
- a.Aphasmida
- Trichuris trichuria (Whipworm)
- b. Phasmida
- Ascaris lumbricoides (roundworm)
- Ancylostoma duodenale (hookworm in old world)
- Eye worm, Guinea worm, trichinae worm, filarial worm, pin/thread/seat/churn a worm, etc.
2.CLASS; Rotifera
3.CLASS; Nematomorpha
4.CLASS; Gastrotricha
5.CLASS; Kinorhyncha
Some objectives:
1.Which of the following statement is true about the alimentary canal of roundworms?
a.No mouth
b.Only anus
c.Both mouth and anus
d.None of the above
2.Special modification of Ascaris to its parasitic mode of life is
a.Straight and uncoiled alimentary canal
b.Segmented body
c.Resistant cuticle on the body surface
d.Cylindrical body
3.Filarial is a
a.Protozoa
b.Virus
c.Helminth
d.Bacteria
4.Which of the following is true for Ascaris?
aOutside ---------> intestine ---------> liver ---------> lungs ---------> trachea ---------> oesophagus ---------> intestine
b.Outside ---------> stomach ---------> heart ---------> lungs ---------> trachea ---------> intestine
c.Outside ---------> intestine ---------> heart ---------> lungs ---------> traches ---------> intestine
d.Outside ---------> stomach ---------> liver ---------> lungs ---------> oesophagus --------->
5.Amphid and phasmid gland are found in:
a.Platyhelminthes
b.Annelida
c.Nematode
d.Cockroach
6.The wandering journey of Ascaris takes:
a.10days
b.12days
c.14days
d.20days
7.Which of the following disease is caused by nematode?
a.Filariasis
b.Amoebiasis
c.Leprosy
d.Malaria
8.The space between the bodywall and the alimentary canal of Ascaris is known as
a.Haemocoel
b.Coelom
c.Pseudocoel
d.Enterocoel
9.The animal in which sexes can be differentiated from external morphology is:
a.Taenia
b.Krait
c.Ascaris
d.Sea anemone
10.Filaria can be eradicated if the population of the following is exterminated:
a.Cockroach
b.Housefly
c.Culexs mosquito
d.Anopheles mosquito
11.Amphids present in ventrolated lips od Ascaris are;
a.Chemoreceptors
b.Gustatoreceptors
c.Olfactoreceptors
d.Tactoreceptors
Note; both chemoreceptors and olfactoreceptors is the answer but if we have to choose between the best answer we have to go to the olfacoreceptors
12.Which one has no intermediate agent to cause disease?
a.Tapeworm
b.Roundworm
c.Plasmodium
d.Liverfluke
13.The correct matching about bodywall of Ascaris is:
a.Flame cell and circular body
b.Pseudo coelom and longitudinal body muscle
c.Longitudinal muscle and syncytial epidermis
d.Syncytial epidermis and diploblastic body
14.Which of the following parasites causes iron deficiency anemia?]
a.Pinworm
b.Roundworm
c.Hookworm
d.Tapeworm
15.Which of the following penetrates through human skin?
a.E. histolytica
b.Roundworm
c.Hookworm
d.Tapeworm
16.In hookworm, ingested blood is prevented from clotting by forment secreted by:
a.Esophageal gland
b.Salivary gland
c.Pharyngeal gland
d.Tonsillar gland
17.The alimentary canal of nematode is:
a.Only mouth
b.Only anus
c.Mouth and anus
d.No intestine
18.Hookworm infection causes the deficiency of:
a.Vitamin B12
b.Vitamin A
c.Iron
d.Folic acid
19.Filariform larva is infected stage of;
a.Ascaris
b.Threadworm
c.Tapeworm
d.Hookworm
20.The organism which is not blood parasite:
a.Plasmodium
b.Trypanosome
c.Trichinella
d.L.donovani
21.After how many moults, does a roundworm grow into an adult in human intestine?
a.1
b.2
c.3
d.4
22.Ascaris lumbricoide is;
a.Didelphic
b.Monarchic
c.Both a and b
d.Monoecious