Biology Questions and Answers
Chordates
- What are the two main
subdivisions of the phylum
Chordata?
The phylum Cprotochordates (uhordata is divided intorochordates and
cephaloch(cyclostomes,ordates) a fishes, amnd vertebratesphibians,
reptiles, birds and mammals).
- What are the three
structures shared by every
chordate that characterize the
group?
All beings of the phylum Chordata hbranchial clefts in the pharynx (in someave (^)
species prnotochord (substituted by esent only in the embryo),the spinal
column in vertebrates) and dorsal
neural tube.
- What is the destination of
the branchial clefts in
humans?
In humans the branchial clefts locatedin the anterior region of the pharynx
(also known as pharyngeal clefts) are
present only disappear later.in the embryonic stage and
- What is the destination of
the notochord in vertebrates
and in protochordates?
In vertebrates thand gives birth to the notoce spinal columnhord disappears
(vertebral column). the notochord remains for the rest ofIn protochordates
the life. - Is the tubular-dorsal
nervous system of chordates
associated to radial or lateral
symmetry? How does that
explain the complexity level of
the nervous system reached
by the vertebrate evolutionary
branch?
The tubular and dorsal nervous system
of chordates is relatecephalization in these animals and to the (^) d to
bilateral symmetry.
The presence of neural integratincenters with concentration of neurons ing (^)
the brains annervous system,d the spinal cor CNS) allowed thed (central
increase of the interaction complexity
between these animalsenvironment. Receptor and the(afferent (^)
conduction) and efferent (motor,
regulatoryfunctions com and behavioral re out more sophisticatedeactions) (^)
in chordates due to the presence of
more well-developed neural networks.These features have been preserved by (^)
evolution advantage as they provide adaptiveto their owners.
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