Why Would Exposure to a Harmful Chemical During the First

question 36

Essay

Why would exposure to a harmful chemical during the first trimester be more likely to produce a major birth defect in a developing human than exposure to the same chemical during the last trimester?

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Definitions:

Papillae

Projections on the surface of the tongue that contain taste buds, involved in the sensation of taste.

Ileocecal Sphincter

A muscular valve that controls the flow of digested food from the small intestine to the large intestine.

Ileum

The final and longest segment of the small intestine, where the absorption of vitamins, electrolytes, and other nutrients is completed.

Cecum

The first part of the large intestine, connected to the ileum and ascending colon, playing a role in the digestive process.