Question

placental peptide hormones cause maternal ____________. a increase in blood oxygen levels b striae gravidarum c resistance to insulin by body cells d drop in blood pressure

Explanation:

Placental peptide hormones, such as human placental lactogen (hPL), contribute to insulin resistance in maternal cells. This is an important physiological adaptation during pregnancy as it helps ensure that sufficient glucose is available for the developing fetus.

• Option A: Placental peptide hormones do not directly cause an increase in maternal blood oxygen levels. Gas exchange in the placenta is a physical process related to the structure of the placenta and maternal - fetal circulation, not a direct hormonal effect on blood oxygen levels.
• Option B: Striae gravidarum (stretch marks) are mainly due to the mechanical stretching of the skin as the uterus enlarges during pregnancy, not a direct effect of placental peptide hormones.
• Option D: Placental peptide hormones are not the main cause of a drop in maternal blood pressure. Blood pressure changes during pregnancy are complex and involve multiple factors such as changes in blood volume, vascular tone, etc., but placental peptide hormones are not the primary driver of a drop in blood pressure.

Answer:

C. resistance to insulin by body cells