Which term describes all organisms that have a backbone, paired appendages, and bilateral symmetry? a. axial b. vertebrate c. appendicular d. mammalian

Ais a group of individuals of the same that exist together in the same place at the same time

What did not occur in the proterozoic eon a)the oxygen levels increase greatly in the atmosphere,b)the emergence of the eukarya , c)muti cella’s eukaryotic organisms began to diversify,d)anaerobic bacteria kept thriving with more oxygen

The nervous system interacts with the endocrine system by a. using hormones as connections b. sending nerve impulses directly to glands c. using neuroendocrine cells as connections d. sending neurotransmitters directly to neurons