Explain why your body feels like it is being pushed back when the car starts back up again

This push is felt due to inertia

Inertia is the resistance, of any physical object, to any change in its velocity. This property is also called the first law of motion which says a body in rest will remain at rest and a body in motion will stay in motion until an external force acts upon them. The same thing happens when our body is at rest and the car suddenly starts backing up again. Because the rest state of our body experiences a sudden push and our body resist it due to inertia.

cell differentiation  is how generic embryonic  cells  become specialized  cells. this occurs  through a process called gene expression. gene expression is the specific combination of genes that are turned on or off (expressed or repressed), and this is what dictates how a  cell  functions.

explanation:

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