Gastrointestinal Absorption Flashcards
(16 cards)
What are the three structures of the small intestine?
- Duodenum
- Jejunum
- Ileum
What is the duodenum?
The first segment of the small intestine where further digestion occurs including of fats
What is the jejunum?
The second segment of the small intestine where most of the absorption of nutrients occurs
What is the illeum?
The third and longest segment of the small intestine where some absorption occurs particularly vitamins and bile salts
What allows glucose and galactose to enter the intestinal mucosa?
Apical SGLT with Na+
What allows fructose to enter the intestinal mucosa?
GLUT5
What allows glucose, galactose and fructose to enter so exit the intestinal mucosa?
GLUT2
How are proteins mainly abosrbed?
As amino acids
What are the three ways proteins are absorbed?
- Di/Tripeptides cotransport with H and PepT1
- Amino acid cotransports with Na
= Small peptides carried across the cell
How are lipids absorbed?
Are broken down into micelles by bile salts and enter the cell via diffusion
How is cholesterol absorbed?
It must be transported
How are lipids transported in the body?
In the lymphatic system as chylomicrons
What are the six parts of the large intestine?
- Cecum
- Ascending colon
- Transverse colon
- Descending colon
- Sigmoid colon
- Rectum
What is a haustral contraction in the large intestine?
Slow segmenting movements that mix chyme and promote water absorption
What is mass peristalsis in the large intestine?
Strong coordinated contractions that propel waste material towards the rectum preparing it for defecation
What is the valsalva maneuver?
When you hold your breath/close you epiglottis to strain when defecating
