Answer: Option A
Explanation:
A tunicate is marine invertebrate animal which is a part of chordates. They have notochords and dorsal nerve chord. The subphylum of the organism is called as Urochordata.
The adult urochordates lack notochord but the larval stage of the urochordates have notochord. This is because it helps in swimming of the organism which is required only at the larval stage.
The adult stage of the tunicates is sessile and they do not swim so they do not require notochord.
The nucleus is what houses the cells genetic information. Hope this helps!
Answer: Louis Pasteur
Louis Pasteur in 1860s, proposed germ theory. The theory was based upon the fact that diseases are caused by the microorganisms.He was officially the first to publish his work.
Answer:
adding chlorine, checking the water.
Explanation:
Because this increases the quality of the water while the rest improve either quantity, or ease of access.