Digestive System Physiology

What is the primary hormone released by the stomach endocrine cells after neural stimulation?

Which hormone is released by the endocrine cells of the duodenum in response to increased chyme volume?

How does secretin affect pancreatic function in the presence of chyme?

What blood glucose level indicates hyperglycemia in adults?

Which condition can result from hypoglycemia?

Gastrin's role in digestion

Normal blood glucose levels

Blood glucose response after a meal

Stomach Control

Stomach endocrine cells release gastrin upon neural stimulation
Gastrin stimulates gastric juice secretion (HCl, mucus, water, pepsin activation)
Positive feedback loops prepare the stomach for food intake

Chyme and Duodenum Control

When chyme enters the duodenum, endocrine cells release CCK (cholecystokinin)
CCK triggers gallbladder bile release for lipid emulsification
CCK levels directly correlate with chyme levels in the duodenum
Secretin is released by duodenum endocrine cells in response to chyme
Secretin increases pancreatic enzyme formation and bicarbonate production
Secretin stimulates pancreatic secretions to mix with chyme
Secretin levels in blood are proportional to chyme levels in the duodenum

Liver Bile Secretion

Liver bile production and secretion are not hormonally controlled

Blood Glucose Homeostasis

Normal blood glucose levels in adults are 3-4.5 mmol/dL
Hyperglycemia (high blood glucose) can cause tissue damage, glaucoma, swelling, and neural diseases
Hypoglycemia (low blood glucose) can cause temperature issues, hypotension, and bradycardia
Post-meal blood glucose rises to ~5.0 mmol/dL (trigger level)
Between meals, blood glucose levels fall to ~3.5 mmol/dL (trigger level)

Test your knowledge on the control mechanisms of the stomach, chyme, and liver bile secretion. This quiz covers important hormones involved in digestion and blood glucose homeostasis. Challenge yourself to understand the processes that regulate digestion and nutrient absorption.