Lecture: Nematodes

Question 1

Adult nematodes are…

Answer 1

unsegmented, elongated, cylindrical worm

Question 2

All of the viscera including the digestive system, excretory system and the reproductive system are suspended in a body cavity known as

Answer 2

Pseudocele or Pseudocoelum

Question 3

Fluid of pseudocele

Answer 3

Hemolymph

Question 4

Esophagus of nematodes that are simple, long and slender; seen in Strongyloides

Answer 4

Filariform

Question 5

Esophagus of nematodes that is divided into distal corpus, an isthmus and an esophageal bulb; seen in Enterobius

Answer 5

Rhabditiform

Question 6

Type of nematode esophagus that has an anterior portion muscular, posterior glandular; seen in Filarial worms

Answer 6

Spiruroid

Question 7

Type of nematode esophagus that is short, muscular with a waist, seen in Ancylostoma

Answer 7

Strongyliform

Question 8

Type of nematode esophagus that is long, thin, capillary-like lined with esophageal gland cells; seen in Trichuris, Capillaria and Trichinella

Answer 8

Stichosoma

Question 9

Esophageal gland cells of nematodes

Answer 9

Stichocytes or Stichosomes

Question 10

Minute inflations of the cuticle, which function as tactile receptors

Answer 10

Papillae

Question 11

Paired minute chemoreceptor organs located in the cephalic or cervical region of all nematodes are known

Answer 11

Amphids

Question 12

Pair of minute lateral post anal or caudal chemoreceptor organ present in some species of nematodes without caudal glands is known

Answer 12

Phasmids

Question 13

Eggs are oviposited and the embryo develops outside the maternal body as in Ascaris, Trichuris

Answer 13

Oviparous

Question 14

Where the adult female gives birth to a larva as in Trichinella spiralis and Filarial worms

Answer 14

Viviparous or Larviparous

Question 15

The female can produce viable eggs without being fertilized by the male worms as in Strongyloides stercoralis

Answer 15

Parthenogenetic

Question 16

Formed immediately after sperm penetration; waxy, colorless and lipoidal in nature

Answer 16

Vitelline membrane

Question 17

Secretory product of the egg; chitinous in nature and synthesized from glycogen and ovarian nitrogen

Answer 17

Chorionic or True Shell

Question 18

Outermost layer of the egg; has a tanning action

Answer 18

Albuminous layer

Question 19

Requires a definitive host but does not require an intermediate host; from the egg stage it develop into the infective stage

Answer 19

Direct or Homogonic

Question 20

Requires both a definitive host and one or two intermediate hosts for the development into infective stage

Answer 20

Indirect or Heterogenic

Question 21

Nematodes with only one host are…

Answer 21

Homoxenous

Question 22

Nematodes with more than one host are…

Answer 22

Heteroxenous

Question 23

Classification of nematodes without caudal chemoreceptor organ (phasmids) and is provided with caudal glands

Answer 23

Class Enoplea / Class Adenophorea / Class Aphasmidea

Question 24

Classification of nematodes with caudal chemoreceptor organ (phasmids) and is without caudal glands

Answer 24

Class Rhabditea / Class Secernentia / Class Phasmidea

Question 25

Nematodes in Class Enoplea

Answer 25

Trichuris trichiura Trichinella spiralis Capillaria philippinensis

Question 26

Nematodes in Class Rhabditea

Answer 26

Ascaris lumbricoides Strongyloides stercoralis Enterobius vermicularis Angiostrongylus cantonensis Filarial worms Hookworms Dracunculus medinensis

Question 27

Nematodes that inhabits the small intestine

Answer 27

Ascaris lumbricoides Capillaria philippinensis Hookworms Strongyloides stercoralis

Question 28

Nematodes that inhabits the large intestine

Answer 28

Trichiuris trichiura Enterobius vermicularis

Question 29

Nematode that inhabits muscles

Answer 29

Trichinella spiralis

Question 30

Nematode that inhabits lymphatic system and tissue

Answer 30

Filarial worms

Question 31

Nematode that inhabits tissue

Answer 31

Dracunculus medinensis

Question 32

Nematode that inhabits brain

Answer 32

Angiostrongylus cantonensis

Question 33

Two types of muscle cells in the body wall

Answer 33

Platymarian Muscle Cells Coelomyarian Muscle Cells

Question 34

Supporting body wall of nematodes consists of

Answer 34

Outer hyaline, non-cellular cuticle Subcuticular epithelium or hypodermis Layer of muscle cell or somatic musculature

Question 35

Responsible for the secretion of cuticle

Answer 35

Subcuticular epithelium or hypodermis

Question 36

Outermost layer of the outer hyaline, non-cellular cuticle which is composed of collagen and cuticulin

Answer 36

Cortical Layer

Question 37

Middle layer of the outer hyaline, non-cellular cuticle

Answer 37

Homogenous Matrix

Question 38

Inner layer of the outer hyaline, non-cellular cuticle

Answer 38

Fibrous Layer

Question 39

Constitutes the nerve center for nematodes

Answer 39

Circum-Esophageal Ring Commissure

Question 40

Oviparous parasites

Answer 40

Ascaris and Trichuris

Question 41

Viviparous/Larviparous parasites

Answer 41

Trichinella spiralis Filarial worms

Question 42

Parthenogenetic parasite

Answer 42

Strongyloides stercolaris