Nematodes

• the adult nematode is?

  unsegmented, elongated, and cylindrical worm
• length ranges of nematodes?

  2mm to more than a meter
• characteristics of male nematodes?

  head, anterior, curve head and smaller than female
• female nematodes characteristics?

  tail, posterior, pointed tail
• body wall consists of?

  outer hyaline, subcuticular epithelium or hypodermis and somatic musculature
• it is responsible for the secretion of the cuticle?

  subcuticular epithelium or hypodermis
• it is a non cellular cuticle?

  outer hyaline
• body cavity is also known as?

  pseudocele or pseudocoelum
• where is pseudocele located?

  found in the internal organ of nematode
• what is hemolymph?

  it is the fluid of pseudocele
• hemolymph consists of?

  hemoglobin, vitamins, glucose, proteins and salt
• body wall and hemolymph serves as?

  hydroskeleton of nematodes
• purpose of mouth in the digestive system?

  abrasion, attachment and sensory response
• purpose of buccal cavity in the digestive system?

  a tubular or funnel-shaped and expanded for sucking purposes
• function of esophagus in the digestive system?

  pumps food into the intestine and is useful for species identification
• types of esophagus?

  filariform, rhabditiform, spiruroid, strongyliform, stichosoma
• it is seen in strongyliform?

  ancylostoma
• rhabditiform is seen in?

  enterobius
• filarial worm is seen in?

  spiruroid
• stichosoma is seen in?

  trichuris, capillaria and trichinella
• it is seen in filariform?

  strongloides
• purpose of intestine/midgut?

  absorbs nutrients and probably plays a role in the excretion of nitrogenous waste products
• the most important commissures?

  circum-esophageal ring
• it is the brain of the nematode?

  circum-esophageal ring
• it constitutes the nerve center?

  commissure
• sensory receptors of nematodes?

  papillae
• 2 types of papillae?

  amphids and phasmids
• it is found in posterior?

  phasmids
• all nematodes have it?

  amphids
• it is found in the anterior?

  amphids
• male reproductive system?

  curve tail grasp female during copulation
• types of female adults?

  oviparous, viviparous or larviparous and parthenogenetic
• it gives birth to a larva?

  viviparous or larviparous
• can be pregnant with or without male worms?

  parthenogenic
• gives birth to an egg?

  oviparous
• example of oviparous?

  ascaris and trichuris
• example of larviparous?

  trichinella spiralis and filarial worm
• example of parthenogenetic?

  Strongyloides stercoralis
• life cycle?

  egg, larva and adult
• Direct (Homogonic)


  Requires a definitive host but does not require an intermediate host; from the egg stage it develops into the infective stage. Nematodes with only one host are homoxenous