Professionals that study and make predictions about human population are called demographers.
The period during which the presence of stromatolites decline is the Proterzoic period. Stromatolites are widely distributed sedimentary structures consisting of laminated carbonate or silicate rocks, produced over geologic time by the trapping, binding, or the precipitating of sediment by groups of microorganisms, primarily cyanobacteria.
Answer:
Vertebrates contain nervous system which is highly specialized organ.
Explanation:
The nervous system is the complex system in the vertebrate body which is composed of central nervous system that contain brain,spinal cord and peripheral nervous system which contain cranial nerve, spinal nerve,involuntary nerve etc.
The nervous system contain neurons that mainly transmit signal to the different parts of the body.
The peripheral nervous sytem contain somatic and visceral part.
The grey matter and white matter are the 2 areas in vertebrate nervous system.
You see, passive transport needs no energy. So that being said, it moves from areas with high concentration to areas with low concentration.
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