Ans. is 'b' i.e., 10 - 12 week Age of fetus End of Ist month Impoant changes Length -1 cm, weight -21/2 gm Eyes are seen as two dark spots and mouth as a cleft Nucleated RBCs begin to form in placenta End of 2nd month Length -4 cm, weight - 10 gm First ossification center appears in clavicle (4-5 weeks) The anus is seen as dark spot End of 3rd month Length -9 cm, weight - 30 gm Nails appear and neck is formed End of 4th month Length -16 cm, weight - 120 gm Sex can be recognized Lanugo hair is seen Meconium is found in duodenum Convolution begins to develop in brain End op' month Length -25 cm, weight - 400 gm Nails are distinct and soft Meconium appears in beginning of large intestine Light hair appear on head Skin is covered with vernix caseosa End of 6th month Length -30 cm, weight - 700 gm Eyebrows and eyelashes appear Testes are seen close to kidney Meconium in transverse colon End of 7`" month Length -35 cm, weight - 900 to 1200 gm Meconium in entire large intestine Tests are found at external inguinal ring Eyelids open and pupillary membrane disappear End of 8th month Length -40 cm, weight - 1.5-2 kg Nails reach the tips of fingers Left testis is present in scrotum End of 9th month Length -45 cm, weight - 2.2-3.0 kg Scrotum contains both testes Meconium is seen at the end of large intestine End of Ir month Length -48-52 cm, weight - 2.5-5 kg (full tenn child) Six fontanels are present Surface of brain shows convolution and grey matter begins to form Lanugo is absent except on shoulders. Skin is pale and covered with vernix caseosa The nails project beyond the tip of fingers, but reach only the tip of the toes Cailages have formed in nose and ears.