Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 1 version 1.0 Birth Activity 3: Development A teaching sequence from the A&E unit cracking science!

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 2 How can one cell turn into a baby? Chloe and Jack are excited. Chloe is pregnant at last. What changes take place as an embryo grows? As the embryo grows, cells multiply, differentiate and arrange themselves into organs. Darcy explains how twins are formed, and why Chloe’s must be identical. Chloe had one embryo implanted, but now she’s expecting twins. 7E Learning Cycle

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 3 We decided to have one embryo implanted. 2 weeks later… I didn’t want to take any risks. Engage ElicitExploreExplainElaborateExtendEvaluate

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 4 But guess what! Engage ElicitExploreExplainElaborateExtendEvaluate

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 5 Chloe took a pregnancy test this morning. It was positive. She’s pregnant! Engage ElicitExploreExplainElaborateExtendEvaluate

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 6 The embryos were so tiny! How does one cell become a baby? EngageElicit ExploreExplainElaborateExtendEvaluate

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 7 I’ll leave you to explain the changes that take place. Our growth data cards should help. Engage ExploreExplainElaborateExtendEvaluateElicit Student Sheet 1

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 8 As an egg becomes an embryo, cells divide repeatedly…...and the new cells specialise to form tissues and organs. Engage ExploreExplainElaborateExtendEvaluateElicit

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 9 On days 2 – 5, the cells divide to make a ball of smaller cells. Engage ExploreExplainElaborateExtendEvaluateElicit Student Sheet 2

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 10 From day 6, new cells specialise to do different jobs. The outer cells embed in the uterus lining and begin to form a placenta. Engage ExploreExplainElaborateExtendEvaluateElicit

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 11 As cells multiply and specialise, tissues form and organs begin to appear. By week 4 the embryo’s brain and heart are working. Engage ExploreExplainElaborateExtendEvaluateElicit

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 12 By week 10 all its organs have formed. It becomes a fetus. Engage ExploreExplainElaborateExtendEvaluateElicit

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 13 With help, the fetus could survive outside the uterus after 22 weeks…...but they are usually born after 40 weeks. Engage ExploreExplainElaborateExtendEvaluateElicit

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 14 I’ve just had my first check-up. It was a bit of a shock! 8 weeks later… Engage ExploreExplainElaborateExtendEvaluateElicit

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 15 ANTENATAL CLINIC REVIEW VISIT SUMMARY Date of visitGestationBPFetal heartWeight 28/0210/40120/80 FHHR 2 detected 58kg Chloe’s midwife sent the notes from her check-up. Notice anything unusual? Engage ExploreExplainElaborateExtendEvaluateElicit

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 16 They must have put two in by mistake. But I can’t be having twins – we only implanted one embryo. Engage ExploreExplainElaborateExtendEvaluateElicit

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 17 There is another explanation. Think about it. What could have happened to that embryo? Engage ExploreExplainElaborateExtendEvaluateElicit

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 18 So if the ball of cells splits you can get two identical babies. Every cell in a 3-day embryo is identical and can make a complete baby. Engage ExploreExplainElaborateExtendEvaluateElicit

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 19 But how can a ball of cells turn into two whole babies? And will they definitely be exactly the same? Engage ExploreExplainElaborateExtendEvaluateElicit

Activity from the A & E unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original Birth 3: Development 20 Picture credits Picture Slide Credit Background 3, 4, 6Alice Elizabeth Still