A lake that freeze over is helpful to the organisms inside the water because, the solid ice serves as a barrier between the water and the cold air above the water. The ice prevents the chilled air surrounding the water body from getting to the organisms inside the water. <span />
Answer:
In anatomy, the notochord is a flexible rod formed of a material similar to cartilage. If a species has a notochord at any stage of its life cycle, it is, by definition, a chordate. The notochord lies along the anteroposterior ("front to back") axis, is usually closer to the dorsal than the ventral surface of the animal, and is composed of cells derived from the mesoderm.
A plant who has had intercourse many times
A signaling pathway would need to be regulated because of efficiency, to make what you need when you need it.
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