The chorionic villi 

(a) Form the umbilical cord

(b) Form the umbilical vein

(c) Form the umbilical arteries

(d) Increase the surface area available for exchange between the placenta and maternal blood

(e) Form the portion of the placenta called the capsular decidua

Identify the two extra-embryonic membranes and the three different regions of the endometrium at week 10 of development in the following diagram.

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a. ___

b. ___

c. ___

d. ___

e. ___

The hormone that is the basis for a pregnancy test is 

(a) LH

(b) Progesterone

(c) Human chorionic gonadotropin (hCG)

(d) Human placental lactogen (hPL)

(e) Either c or d, depending on the type of test

Recessive X-linked traits 

(a) Are passed from fathers to their sons

(b) Are more likely to be expressed in males

(c) Always affect some aspect of the reproductive system

(d) Are never expressed in females

(e) Cannot be passed from mothers to daughters