CHORDATES

Chordates differ from invertebrates:
1. presence of the notochord
2. do not have a tail
3. they have a nervous system on the abdominal side of the body
When did chordates appear for the first time?
1. in late Primary
2. in Secondary
3. in Tertiary
We count among tunicates:
1. the sea squirts and the branchiostoma
2. the sea squirts and the thaliacea
3. the branchiostoma
A part of plankton are:
1. the sea squirts
2. the thaliacea
3. the branchiostoma
In adulthood............ live sessily.
1. the sea squirts
2. the thaliacea
3. the branchiostoma
....................... lives in sand shallows of warmer seas.
1. A branchiostoma
2. A sea squirt
3. A thaliacea
A branchiostoma moves:
1. by lateral waving
2. thanks to the tail
3. crawl on the sea-floor
.............. have a big regenerative ability.
1. The sea squirts
2. The thaliacea
3. The branchiostoma
We find a difficult reproduction:
1. with the branchiostoma
2. with the sea squirts
3. with the thaliacea
.....lives buried in sand during the day.
1. A branchiostoma
2. A sea squirt
3. A thaliacea