Sentence examples for tunicates from inspiring English sources
In tunicates, added support is provided by the tunic.
Tunicates largely rely upon the passive defense afforded by their heavy tunic.
Free-swimming tunicates metamorphose without attachment.
The tail musculature of tunicates is simpler and without clear indications of segmentation.
In tunicates and vertebrates the blood is propelled by a distinct heart; in cephalochordates, by contraction of the blood vessels.
In tunicates and cephalochordates, organs have been identified that correspond in anatomical position to the pituitary gland of vertebrates, but which hormones, if any, they secrete is uncertain.
A free-swimming tunicate larva metamorphoses into an attached, sessile adult with an atrium that surrounds the gills.
An alternative theory is that the ancestor was like a tunicate and that the other two subphyla arose by modification of the tadpole larva.
Appendicularians probably evolved from a more typical tunicate that reached sexual maturity before metamorphosis occurred.
In tunicate larvae, this is accomplished using a tail; in cephalochordates, by undulations of the body; and in vertebrates, by general body movements (as in eels and snakes) and by the action of fins and limbs, which in birds and some mammals are modified into wings.
The tunicate heart is unusual in that it periodically reverses the direction in which it pumps the blood, but the reasons for this behaviour are unknown.
