Small Intestine

What is the order of the small intestine

1. Duodenum

2. Jejunum

3. Ileum

How long is the duodenum?

10 inches

How long is the jejunum?

8 feet

How long is the ileum?

12 feet

What part receives chyme, bile, and pancreatic juice

Duodenum

What part is the major site of absorption?

Jejunum

What part is where the absorption continues at the end of the cecum?

Ileum

Where is the ileocecal valve?

between small intestine and large intestine

What is the purpose of the ileocecal valve?

prevents chyme from re-entering the small intestine

What is histology of the Small Intestine?

Villi and microvilli are in the intestine

What do villi and microvilli do?

Increase the surface area to help absorption

What are inside each villus?

capillaries and lacteal

What are capillaries?

Smallest blood vessels

What are lacteals?

Intestinal lymphatic vessels

What do they both do?

they absorb fatty acids and glycerol into the lymphatic system

What is the lymphatic system?

the network of vessels through which lymph drains from the tissues into the blood

What do carbs break down into in the SI?

maltase, sucrose and lactose

What does lactase break down into?

maltose into glucose + glucose

What does sucrase break down into?

sucrose into glucose + fructose

What does lactase break down into?

glucose + galactose

What is it called when disaccharides are now monosaccharides?

Known as carb digestion

What do proteins get broken down into?

amino acids

What is the purpose of peptidase enzymes?

that break down peptides down into individual amino acids so they can be absorbed

What do fats break down into?

fatty acids and glycerol

What is absorption?

happens through epithelial cells into the capillaries and lacteals done by diffusion or active transport

What is the percentage that the small intestine absorbs?

90%

What is the percentage that the stomach absorbs?

10%

What is segmentation?

continues mixing by smooth muscles contractions