Biology Questions and Answers
- Compared to
platyhelminthes which
physiological problem have
the cylindrical body of
nematodes brought? How was
that problem solved?
The cylindrical shape of nematodes
made impossible thexclusively by simple respiratione diffusion amon (^) g
cells since there are tissues far from the
exterior. Tthe presence of an inner cavityhis problem was solved in theby (^)
body filled with flThe pseudocoelom huid, thas the function ofe pseudocoelom.
distributing gases and nutrients to the
body and to collect residserving as a hydrostatic base to uals, besideskeep (^)
the worm shape.
(For the fact that the pseudocoelomfluid and the pseudocoelom do not
characterizwith blood and heart it is not e a true circulatory systemsaid that (^)
in nematodes the respiration is
cutaneous; it is considered that theseanimals still make respiration by
diffusion).
- How does the excretory
system of nematodes work?
The metabolic residuals of nematodes
are collected excretory chaby two longitudinal nnels that open in onelateral
single excretory pore near the mouth.
- How is the nervous system
of nematodes organized?
Where are the neural chords
located in their body?
Roundworms have a ganglial nsystem with an anterior neural ringervous
representincephalization.g (evolutionarily) a primitive
Nematoganglial chords that edes have two xtend one dorsallymain longitudinal (^)
and the other ventrally under the
epidermis. Thlateral to these main choere may also brds. Thee nerves
nervous system of a free-living
nematodhas been well-studie, “Caenorhabditised in elegans”,
neurophysiological research and
presents 302 neurons.
The nematode “C. Elegans” was the
organism usgenetic regulation oed in the research of organogenesis andn the (^)
apoptosis whose researchers won the
Nobel prize of Medicine (Brenner, Horvitz and Sulston).in 2002
- What is the type of
reproduction that occurs in
roundworms? What typical
feature do nematode sperm
cells have?
Nematonematoddes reproduce sexe sperm cell does not have ciliaually. The (^)
nor flagella and they move by amoeboid
movement forming pseudopods.
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