BIOL 4105 Chapter : 7 10 12 Whipworms
Document Summary
Have a complete gi tract: uticle- outer acellular layer fr protection, lines all external openings and is impervious/resistant to chemicals, well-developed muscular system and nervous system, do not absorb any nutrients through the cuticle. They eat and excrete: pseudo coelom- fluid called hemolymph, clear, not compressible. Musculature of the nematode when it contracts it must push the fluid to the other side of the coelo, wavy looking movement. Hydrostatic skeleton is created by the worm: complete gi tract is a simple tube, buccal cavity (mouth, muscular esophagus with glands that release digestive substances. Esophagus has a big, muscular bulb that pushes the ingesta through the gi tract: non muscular intestine with microvilli. Reproduction: dioecious as a rule, some females are ovoviviparous (larvae released from retained, hatched eggs, most females are oviparous, rare- parthenogenic- female produces eggs without the benefit of sperm. Eggs develop into male and female offspring- therefore this is not cloning: sexes find each other by pheromones.
