Fearfully and Wonderfully Made

Gestation – Period of development before birth (38-40 weeks in Humans)

Amniotic Sac – Fluid filled sack that protects the child during gestation

Placenta – Sac of blood vessels that provide the materials from the mother the child needs

Umbilical Cord – The three vessels that transport nutrients and wastes from the placenta to the child

2 to transport nutrients and 1 to transport wastes

Nervous system Week 3 – Neural plate appears which develops into the nervous system

Week 6 – Brain is sending out impulses to control body functions and movements

Week 7 – Will respond to touch

Week 12 – Brain is fully formed but continues to grow

Digestive System Week 3 – Digestive tube is present

Week 6 – Stomach produces digestive juices

Circulatory System 17 Days – Blood cells are present Week 3 – The heart begins to beat

Week 4 – Network of blood vessels is developed Week 8 – Heart is fully developed but continues to grow

Respiratory System Week 4 – Lungs, trachea, and bronchial tubes begin to form but are not used until born

Skeletal System Week 5 - Skeleton is taking shape made mostly of cartilage

Week 8 – Ossification (the replacement of cartilage with bone) starts and continues until age 25

Other Systems Week 6 – Able to move voluntary muscles to move around

Week 6 – Kidneys filter uric acid from the blood

Week 10 – Kidneys are fully functioning

Fertilization

Zygote

Zygote

2 Cells

4 Cells

8 Cells

Blastocyst

Blastocyst

6 Weeks

7 Weeks

8 Weeks

10 Weeks

14 Weeks

16-20 Weeks

18 Weeks

21 Weeks

24 Weeks

25 Weeks

28 Weeks

5 Months

32 Weeks

6 Months