| Term 
 | Definition 
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        | Term 
 | Definition 
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        | Term 
 
        | 1st appearance of pulmonary structures |  | Definition 
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        |  | 
        
        | Term 
 
        | motor fibers begin to appear in the spinal cord to form spinal nerves, followed by dorsal nerve roots consisting of sensory fibers |  | Definition 
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        | Term 
 | Definition 
 | 
        |  | 
        
        | Term 
 
        | right and left heart chambers formed |  | Definition 
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        |  | 
        
        | Term 
 
        | skeleton is formed by mesenchymal model |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | when do cranial nerves emerge |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | skeleton is made of cartilage model |  | Definition 
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        |  | 
        
        | Term 
 
        | connection between sensory and motor occur |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | ossification centers formed in cartilage model of skeleton |  | Definition 
 | 
        |  | 
        
        | Term 
 | Definition 
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        |  | 
        
        | Term 
 
        | active movement from motor units |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | dying back of extra neurons leads to mononeural innervation of motor units |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | production of surfactant begins |  | Definition 
 | 
        |  | 
        
        | Term 
 | Definition 
 | 
        |  | 
        
        | Term 
 | Definition 
 | 
        |  | 
        
        | Term 
 
        | 15% of fetal mass is due to muscle |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | pathways to carry pain are present |  | Definition 
 | 
        |  | 
        
        | Term 
 | Definition 
 | 
        |  | 
        
        | Term 
 
        | 25% of fetal mass is due to muscle |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | myelination of PNS complete |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | vestibular sense complete |  | Definition 
 
        | birth, but continues to develop |  | 
        |  | 
        
        | Term 
 
        | diaphyses of long bones are ossified |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | maturation of sensory pathways |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | auditory system completely myelinated |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | control of sleep/awake and social behavior CNS organization occurs |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | smooth tracking abilities begin |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | consistent head turning to localize sound |  | Definition 
 | 
        |  | 
        
        | Term 
 | Definition 
 | 
        |  | 
        
        | Term 
 
        | vestibular sensitivity increases |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | myelination starts to slow down |  | Definition 
 | 
        |  | 
        
        | Term 
 | Definition 
 | 
        |  | 
        
        | Term 
 
        | laterality/conscious awareness of 2 sides of our body |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | can tell what you're touching without seeing it |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | accurately visually track a moving object like  a baseball |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | new alveoli continue to develop until this age range |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | perceptual judgments mature |  | Definition 
 | 
        |  | 
        
        | Term 
 | Definition 
 | 
        |  | 
        
        | Term 
 
        | depth perception fully mature |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | awareness of vibrations begin to change |  | Definition 
 | 
        |  | 
        
        | Term 
 
        | functional losses of the cardiovascular system become evident |  | Definition 
 | 
        |  |