Identical twins start out as one egg that for some reason splits in two, and both halves develops into individuals. Genetically, they have to be the same.
They have the same DNA.
It sends messages that control all the systems in the body.
The nervous system controls almost every action in the human body. It controls the heart beat, your adrenaline levels, and many other things which can effect an organism.
The endocrine system affects cells with certain receptors .
The nervous system can affect only nearby cells
Nutrients are absorbed into the bloodstream. Starch is broken down by enzymes.
Macromolecules are broken down.
Hormones
The circulatory system is its own system. There are not systems in the circulatory system.
the organs grow larger
Dosage
Collection of data APEX
Hospital costs
eyes develop
lips start to form
Vocal cords develop.
looks
at the end of the first trimester