<span>The embryonic period is the most important phase of development for organ formation. The embryonic period in humans begins at the moment of fertilization and continues until the end of the tenth week of gestation. Rapid growth and differentiation occurs during this period, which produces varied cell types.</span>
I think it is A. they can start to hear sounds at 20 weeks
Determined by its primary structure (sequence of amino acids.)
the sequence of amino acids in an protein is determined by the nucleotides in the DNA encoding it
NOT EXACT DEFINITION: Diseases that can be passed from one living organism to the other. Two examples are flu and several STIs (such as herpes). Sorry I couldn’t think of any more :)
