AP BIOLOGY

Detailed explanation-1: -Most planarians occur in fresh water and are sometimes seen in large masses; some species are marine, others are terrestrial.

Detailed explanation-2: -Use pond or spring water since the chlorine in tap water makes it toxic to planaria. If tap water is used it must be pre-treated with a Water Conditioner 21 W 2316 as recommended on the conditioner product. While planaria can survive in standing water, the water should be aerated for long-term health.

Detailed explanation-3: -How do planarians eliminate excess water from their bodies? Flame cells collect excess water, which is then transported through excretory tubules and excreted from the numerous poor scattered over the body surface.

Detailed explanation-4: -Planarians are simple multicellular animals known as flatworms. They can regenerate parts of their bodies using adult stem cells called neoblasts. When part of a planarian is cut off, its neoblasts multiply to make more stem cells.