A friend who works in fertility asked me to make a crochet spermatozoon for her. It occurred to me that it could also be a fun way to teach Biology to children!
Start with white yarn.
Rnd 1: ch 2, work 6 dc into first ch - 6 st.
Rnd 2: 2 dc in each st around - 12 st.
Rnd 3: dc in each st around - 12 st.
Rnd 4: [2 dc in next st, dc in next st] 6 times - 18 st.
Rnd 5: dc in each st around - 18 st.
Rnd 6: [2 dc in next st, dc in next 2 st] 6 times - 24 st.
Rnd 7: dc in each st around - 24 st.
Rnd 8: [2 dc in next st, dc in next 3 st] 6 times - 30 st.
Rnd 9: dc in each st around - 30 st.
Rnd 10: [2 dc in next st, dc in next 4 st] 6 times - 36 st.
Rnd 11: dc in each st around - 36 st.
Rnd 12: [2 dc in next st, dc in next 5 st] 6 times - 42 st.
Rnd 13: dc in each st around - 42 st.
Rnd 14: [2 dc in next st, dc in next 6 st] 6 times - 48 st.
Rnd 15-26: (12 rounds) dc in each st around - 48 st.
Rnd 27: [dc in next 6 st, dc2tog] 6 times - 42 st.
Rnd 28: [dc in next 5 st, dc2tog] 6 times - 36 st.
Rnd 29: [dc in next 4 st, dc2tog] 6 times - 30 st.
Rnd 30: [dc in next 3 st, dc2tog] 6 times - 24 st.
Rnd 31-42: (12 rounds) dc in each st around - 24 st.
Rnd 43: [dc in next 2 st, dc2tog] 6 times - 18 st.
Rnd 44: [dc in next st, dc2tog] 6 times - 12 st.
Rnd 45-56: (12 rounds) dc in each st around - 12 st.
Rnd 57: [dc in 4 next st, dc2tog] 2 times - 10 st.
Rnd 58-69: (12 rounds) dc in each st around - 10 st.
Rnd 70: [dc in 3 next st, dc2tog] 2 times - 8 st.
Rnd 71-122: (52 rounds) dc in each st around - 8 st.
Rnd 123: dc in 6 next st, dc2tog - 7 st.
Rnd 124: dc in each st around - 7 st.
Rnd 125: dc in 5 next st, dc2tog - 6 st.
Rnd 126: dc in each st around - 6 st.
Rnd 127: dc in 4 next st, dc2tog - 5 st.
Rnd 128: dc in each st around - 5 st.
Rnd 129: dc in 3 next st, dc2tog - 4 st.
Rnd 130: dc in each st around - 4 st.
Rnd 131: [dc2tog] 2 times, sl st and fasten off - 0 st.
