week 14: lemon
Your adorable little fetus is busy with thumb sucking, toe wiggling, and (not so cute but equally amazing) making urine and breathing amniotic fluid as the liver, kidneys and spleen continue to develop. Lanugo (thin, downy hair) is growing all over the body for warmth.
week 15: orange
Continuing the march towards normal proportions, baby's legs now outmeasure the arms. And, finally, all four limbs have functional joints. Your fetus is squirming and wiggling like crazy down in the womb, though you probably still can't feel the movements.
Source: the bump