Answer:
Virus
Explanation:
Viruses are even smaller than bacteria and require living hosts — such as people, plants or animals — to multiply. Otherwise, they can't survive. When a virus enters your body, it invades some of your cells and takes over the cell machinery, redirecting it to produce the virus.
The law of conservation of energy states that energy can neither be created nor destroyed - only converted from one form of energy to another. This means that a system always has the same amount of energy, unless it's added from the outside.
It's a PDR or the more simple answer would be just a medical dictionary
Through a series of stages, Piaget proposed four stages of cognitive development: the sensorimotor, preoperational, concrete operational and formal operational period. The sensorimotor stage is the first of the four stages in cognitive development which "extends from birth to the acquisition of language".
