2340
This chapter focuses on the morphology of blood vessel formation in and around the early central nervous system ( CNS , i . e . , brain and spinal cord ) of avian embryos .
 blood vessel, central nervous system, CNS, brain, spinal cord, embryos
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Anatomy 
Text: {0} 
Answer:
 blood vessel, central nervous system, CNS, brain, spinal cord, embryos