Answer:
cnidarians
Explanation:
Cnidarian is a phylum of organisms that comprises of the simplest forms of multicellular organisms. Examples of cnidarians includes; coral animals, jellyfish, and sea anemones among others.
They are soft-bodied, carnivorous animals that have stinging tentacles arranged in circles around their mouths. They are the simplest animals to have body symmetry and specialized tissue.
All cnidarians are aquatic, mostly marine organisms, and have two body layers that is the ectoderm and endoderm.
Answer:
Isotonic
Explanation:
A solution is isotonic to a cell if it has the same Concentration of dissolved particles as the cell. Water molecules move in and out of the cell at equal rate, so the cell size remains the same.
There is only one measure of "evolutionary success": having more offspring. A "useful" trait gets conserved and propagated by the simple virtue of there being more next-generation individuals carrying it and particular genetic feature "encoding" it. That's all there is to it.
One can view this as genes "wishing" to create phenotypic features that would propagate them (as in "Selfish Gene"), or as competition between individuals, or groups, or populations. But those are all metaphors making it easier to understand the same underlying phenomenon: random change and environmental pressure which makes the carrier more or less successful at reproduction.
You will sometimes hear the term "evolutionary successful species" applied to one that spread out of its original niche, or "evolutionary successful adaptation" for one that spread quickly through population (like us or our lactase persistence mutation), but, again, that's the same thing.