The Embryonic Period (a) At 4 weeks past conception, the embryo is only about 3 millimetres long, but already the head has taken shape. (b) By 7 weeks, the organism is about 2% centimetres long. Eyes, nose, the digestive system, and even the first stage of finger and toe formation can be seen.
OMIKRON/SCIENCE SOURCE
PETIT FORMAT/SCIENCE SOURCE
PETIT FORMAT/SCIENCE SOURCE