What Stimulus Initiates the Defecation Reflex

question 25

Multiple Choice

What stimulus initiates the defecation reflex?

• A) pressure on the gastroesophageal sphincter
• B) presence of acid in the stomach
• C) the stretch of the rectum
• D) release of secretin and cholecystokinin (CCK) by the small intestine

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Definitions:

Dry Gaseous HBr

Hydrogen bromide gas that is free from water, often used in organic synthesis as a reagent.

Step-by-step Mechanism

A detailed description of every stage in a chemical reaction, explaining the process by which reactants convert into products.

Major Product

The product of a chemical reaction that is formed in the greatest amount, often favored by thermodynamic or kinetic control.

Oxymercuration-demercuration

A two-step organic reaction process used to convert alkenes into alcohols, involving the addition of mercury (II) acetate followed by reduction.