1. UNIT 5 Human reproduction Biology and Geology 3. Secondary Education THE PHASES OF FOETAL DEVELOPMENT

2. UNIT 5 The phases of foetal development FIRST TRIMESTER Month 1 The embryo measures 4 mm. The development of the head begins. The heart is formed and starts to beat. Month 2 The extremities develop. Start of the formation of the brain and the internal organs. Month 3 The fingers and toes form and the nails appear. The eyes are almost completely developed. Biology and Geology 3. Secondary Education

3. UNIT 5 The stages of foetal development SECOND TRIMESTER Month 4 The foetus measures 15 cm. It starts to make movements. The skin is almost transparent. Month 5 The foetus becomes more active and moves more. Hair starts to appear on the head, the eyebrows and the eyelashes. Month 6 The skeleton partially ossifies. The foetus shows some reflexes, such as frowning or sucking its fingers. Biology and Geology 3. Secondary Education

4. UNIT 5 The stages of foetal development Month 7 The foetus is 40 cm long. THIRD TRIMESTER Month 8 The skin thickens and turns a pink colour. The foetus moves into the head-down position. Month 9 The foetus measures between 45 and 50 cm and weighs between 2.5 and 3 kilos. The lungs are fully mature. Biology and Geology 3. Secondary Education