In this IBDP Biology blog post, we will be looking at the function of gastric juices and where and how it is secreted in our bodies.

Gastric juice vs. Pancreatic juice  

Similarities:

• Contain water (universal solvent)
• Contain mucus (as a lubricant or an intestinal lining)
• Contain salts and ions (calcium, phosphate, etc.)

Control of gastric juice secretion 

Pre-Ingestion

• The sight and smell of food triggers a reflex response in which gastric juice is secreted from gastric pits in the stomach wall
• This ensures that gastric juice is in the stomach by the time the food is consumed

Post-Ingestion

• Food entering the stomach causes distension, which is detected by stretch receptors in the stomach lining
• Impulses are sent to the brain, which triggers the secretion of gastrin from the pits lining the stomach wall
• Gastrin causes the sustained release of gastric juice, particularly its acid component
• When the pH drops too low, gastrin secretion is inhibited by hormones  

That is it for this post!

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References:

https://www.google.com/url?sa=i&url=http%3A%2F%2Fwww.old-ib.bioninja.com.au%2Foptions%2Foption-h-further-human-2%2Fh2-digestion.html&psig=AOvVaw0ebcF3Tq5PQUEpmHU0oORD&ust=1627754851749000&source=images&cd=vfe&ved=0CAsQjRxqFwoTCPjahsOxi_ICFQAAAAAdAAAAABAD

https://www.google.com/url?sa=i&url=http%3A%2F%2Fib.bioninja.com.au%2Foptions%2Foption-d-human-physiology%2Fd2-digestion%2Fgastric-secretions.html&psig=AOvVaw1KpzzLeBRgbOXNOXhKwZfR&ust=1627754913265000&source=images&cd=vfe&ved=0CAsQjRxqFwoTCPieruaxi_ICFQAAAAAdAAAAABAg

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