Answer:
Topographically SN is classified into:
1. Central SN- made up of the brain and spinal cord
2. Peripheral SN- made up of nerves (31 pairs of spinal nerves, 12 pairs of cranial nerves), nerve plexuses and nerve ganglia
Structural Dpdv
1. Somatic SN \ of relationship life
2. Vegetative SN a) sympathetic- acts in unusual conditions (eg stress, fear)
b) parasympathetic- acts in normal life conditions
Explanation:
Answer:
Its B
Explanation:
I took the quiz and choose A, but It was wrong, and the correct answer was B... You're welcome :D
Yes. True vertebrates have a true head that develops from a neural crest of cells and hard structures surrounding the notochord.
The neural crest, which forms early in the development process in vertebrate embryos, is a fold on the neural plate where the neural and epidermal ectoderms converge. As an embryo grows, the neural crest produces neural crest cells (NCCs), which can differentiate into a variety of different cell types and contribute to tissues and organs.
The notochord is a temporary structure that plays a crucial role in higher animals. It secretes substances that communicate with all neighbouring tissues, telling them where they are and what will happen to them.
Therefore, True vertebrates have a true head that develops from a neural crest of cells and hard structures surrounding the notochord.
Learn more about notochord here:
brainly.com/question/11871768
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<span>Similarities in the early development of chickens and opossums suggest that these organisms share a common ancestor. It might be difficult to answer such questions without any choices, but knowledge is important. I hope that this answer has actually come to your great help.</span>