Chapter 3, Problem 6RQ

Match each date in column B [approximate time after conception) with a developmental event or stage in column A.

Column A

$\text{\_\_\_\_}$ (1) blastocyst

$\text{\_\_\_\_}$ (2) implantation occurs

$\text{\_\_\_\_}$ (3) first few somites appear

$\text{\_\_\_\_}$ (4) flat embryo becomes cylindrical

$\text{\_\_\_\_}$ (5) embryo/fetus boundary

$\text{\_\_\_\_}$ (6) birth

$\text{\_\_\_\_}$ (7) primitive streak appears

Column B

(a) 38 weeks

(b) 15 clays

(c) 4-7 days

(d) about 21 days

(e) about 21-24 days

(f) end of week 8

(g) clays 6-13