1. a flexible, supporting structure found only in chordates is the (1 point) nerve net.
notochord.
pharyngeal slits.
dorsal fin.
2. ancient chordates are thought to be most closely related to which of the following species? (1 point)
spiders
earthworms
octopi
sea stars

A flexible , supporting structure that are found in chords are  (a) Notochord (b) sea stars (c) the fish with leg like fins was the last to evolve (d) worm  (e) fish.

Explanation:

If the notochord is a flexible rod made out of a material similar to cartilage. The species has a notochord at any stage of its life cycle. The  vertebrates are notochord that  becomes part of the vertebral column.

sea stars are star-shaped echinoderms belonging to the class  of Asteroidea. Echinoderms are more closely related the (vertebrates) than to the most other animals, the  both belong to the same ancient branch of life  Sea stars, also known as starfish, are neither fish nor stars.

a

explanation:

answers are:

lysogenic     viral dna merges with host cell dna

lysogenic     no symptoms

lytic               viral dna takes over

lysogenic     virus does not destroy host cell

lytic               virus destroys host cell

lytic               induces symptoms of viral infection

lysogenic       cell reproduces and spreads provirus