Polyoma vaccine does the Polyomavirus. It’s recommend that parrots get this vaccine yearly.
        
             
        
        
        
Answer:
 of the low pH of the vagina.
Explanation:
The pH of the vagina is maintained at highly acidic levels to prevent the germ buildup. The range of vaginal pH is around 3.8 to 4.5. The very low pH of the vagina creates a hostile environment for sperms and most of the sperms are killed as they enter the vagina due to the acidic pH. 
Apart from supplementing the sperms with energy, cervical mucus serves to protect the sperms from the hostile conditions of the vagina. The cervical mucus has an alkaline pH at or near the ovulation to protect sperms from acidic pH of the vagina and to facilitate fertilization. 
 
        
             
        
        
        
Answer:
Cephalocaudal
Explanation:
The cephalocaudal principle is known as the general process of physical and motoric development which take place from infancy into toddlerhood and at times at early childhood of which development obeys a head-to-toe progression.
Cephalocaudal is a word that connotes head to toe. Therefore, the cephalocaudal principle is stated as the overall process of development observed in the first set of years in postnatal development majorly with the period from infancy into toddlerhood.
The cephalocaudal principle has to do with both physical and functional development. On the basis of the earliest (i.e., physical development), physical growth in size, weight, and feature differentiation obey this process or form of development. The signs of this is well observed in a contrast of the physical characteristics of an infant In contrast to a toddler. In consideration of the latter, the head is mostly disproportionately big in contrast to the other parts of the body. By the time the preschool years is over for most children, it is well noticed that most must have done away with this top heavy appearance just as seen in our question.