Body system

1. Body wall2. Digestive system3. Reproductive

system4. Nervous system5. Excretory system

Body Wall (3 parts)

1. Cuticle2. Hypodermis3. Somatic

musculature

Cuticle

1. produced by hypodermis (non-cellular)2. semipermeable membrane (depending on nature of environment)3. exoskeleton ( 외골격 ) :covers entire body and openings(esophagus, vulva, anus, cloaca, excretory pore, sensory organ) 4. structure-3 layers cortical zone, median zone, basal zone5. chemical compound: collagen(protein)

Hypodermis

1. Beneath the cuticle (syncytial or cellular)2. Major food storage :Lipids(fat), glycogen(carbohydrate) Intense metabolic activity ; Nuclei, mitochondria, endoplasmic recticulum, body nerve3. Two lateral chords, one ventral, and on

e dorsal chord 4. Impermeable

Somatic musculature

1. Beneath the hypodermis2. Single layer of spindle-shaped

cells3. Nematode movement - series of undulation by

coordinated patterns of muscle contraction and relaxation on opposite sides of body

Structure of body wall

Cuticle

Hypodermis

Basement membrane

Somatic musculature

Pseudocoel( 위체강 )

1. Body cavity -not derived from mesoderm2. Provide structural integrity of the bo

dy shape-Hydrostatic skeleton3. Fluid- 장으로 부터의 영양물질을 bo

dy wall 또는 gonad 로의 이동 , 흡수를 용이하게 함 .

4. Fluid is under pressure and aid nematode movement

Digestive system

1. An internal tube extending from oral opening to anus2. Consist of oral opening, stoma, esophagus, es

ophagus-intestinal valve(cardiac), intestine, rectum or cloaca, anus

3. Three parts 1) Foregut-oral opening, stoma, esophagus, cardia 2) Midgut-intestine 3) Hindgut-rectum, cloaca, anus

Foregut

<mouth and stoma>1. Oral opening (mouth) ; 몸통의 가장 앞쪽에 위치 , stoma 로 연결2. Stoma-size and shape ;cylindrical to oval, reduced or inconspicuous 3. Armature(sclerotized) : teeth, denticle, stylet -reflect methods of feeding

Stylet

1. Stomatostylet 1) origin-stoma 2) composed of sclerotized cuticle, lumen(>1um) 3) cone, shaft and stylet knobs 4) diversity in length of stylet and size of knob 5) example: Tylenchida

2. Odontostylet 1) origin-esophageal wall 2) an enlarged tooth with lumen(several um) 3) odontostyle, odontostyle extension, and flanges 4) shed with every molt 5) example: Dorylaimida

Stomatostylet and odontostylet

Cone

Odontostyle

Odontostyle extension

Flange

3. Toothlike odontostylet 1) A ventrally curved, elongated mural tooth 2) consist of solid outer spear and fine inner spear 3) occurred in Trichodorid nematode

Odontostyle

Odontostyle extention

Stomatostylet Odontostylet Tooth

Foregut(Esophagus):portion of digestive system between stoma and intestine1. Lumen-Triradiated muscle2. Glands-one dorsal and two subventral3. Four parts of esophagus 1) Corpus-procorpus and metacorpus 2) Isthmus-cylindrical and short 3) Basal bulb-3~5 glands 4) Cardiac:esophagus-intestinal valve4. Used in systematics characteristics5. Cardiac-prevents the intestinal contents from movin

g forward into the lumen of esophagus

A. CylindricalB. DorylaimoidC. BulboidD. RhabditoidE. DiplogasteroidF~H. TylenchoidI. Aphelenchoid

Midgut(Intestine)

1. extending from the cardiac to the rectum –a tube like structure

2. absorbs nutrients, metabolizes them, stores food, and excretes wastes

(combination of intestine and liver of mammals)

3. Intestinal cells contain stored food material such as glycogen, fatty acid and proteins

(During periods without food, nematode utilize stored food and the intestine becomes clear)

Hindgut

1. Rectum, or cloaca, and anus2. Female, the rectum connected with anus an

d is lined with cuticle3. Male, the reproductive and digestive system

s are jointed posteriorly to form a cloaca and it is lined with cuticle