List the four key morphological traits that characterize all chordates. Discuss the important physiological transitions from early chordates to Craniata and their evolutionary implication
What will be an ideal response?
Answer: All chordates have a notochord, dorsal nerve cord, post anal tail, and pharyngeal slits.
When we compare early chordates to Craniata, we see several physiological transitions such as an increase in the complexity of the nervous system, the formation of a larger brain, a backbone derived from the notochord, an endoskeleton with the cranium, segmented muscles, and large blood vessels. The filter-feeding pharyngeal structures in lancelets and tunicates evolved into a diversity of structures, including gills of fish, jawbones, ear bones, muscles, nerves, and blood vessels. The evolution of these structures resulted in an extensive diversity of vertebrates.
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The anatomy of a body part is closely related to its physiology
Indicate whether the statement is true or false
The photopigment rhodopsin is found in
A. cones. B. rods.
Peptide hormone receptors are located inside the target cell
Indicate whether the statement is true or false