Why would evidence of sense organs in the head of a fossil animal (such as Haikouella) suggest a close relationship with vertebrates that is, which critical vertebrate feature would have to be present?
What will be an ideal response?
Vertebrate sense organs are formed from neural-crest tissue and epidermal placodes, both of which are unique vertebrate features. The presence of such structures in an adult chordate suggests the presence of these vertebrate embryological tissues, and hence a closer relationship to vertebrates than amphioxus or tunicates (which lack these tissues).
You might also like to view...
Lipids are transported to the surface of the intestinal absorptive cells by ________, and are then processed into ________.
A. micelles; fat droplets B. fat droplets; chylomicrons C. fat droplets; micelles D. micelles; chylomicrons
The heart sounds are due to the
A. heart contraction. B. heart relaxing. C. valves closing. D. blood flowing.
The ability to produce endogenous body heat is known as
A) Metabolic hyperthermy. B) Mesothermy. C) Thermogenesis. D) Oxidative metabolism.
Blood plasma is filtered in the ________.
A. renal tubule B. renal calyx C. renal capsule D. renal corpuscle E. renal column