Why did the narrator use the phrase "fit together like puzzle pieces" to describe how the cells of a developing human embryo form a human face?

Match the following terms describing electrical events with the correct phases of the cardiac cycle. the ventricular muscle cells depolarize at the start of this phase. during this phase, na+ entry through the funny channels causes the pacemaker potential of sa nodal cells to gradually become less negative until it reaches threshold. the ventricular muscle cells repolarize right before this phase. the cytosolic concentration of calcium in the contractile cells of the ventricle is highest during this phase. a. isovolumetric relaxation b. ventricular ejection c. isovolumetric contraction d. ventricular filling

Aboy with an extra x chromosome probably has which of the following syndromes?

Which part of the cell is affected by the movement of molecules through diffusion, osmosis and active transport?