GI System Flashcards
What are the four regions of the stomach?
- Cardia
- Fundus
- Body
- Pylorus
Each region has distinct functions in digestion.
What are the two sphincters of the stomach?
The cardiac sphincter and pyloric sphincter.
These sphincters regulate the passage of food into and out of the stomach.
What are the three regions of the small intestine?
- Duodenum
- Jejunum
- Ileum
The small intestine plays a crucial role in nutrient absorption.
What structures in the small intestine increase surface area for absorption?
1.Villi
2. Microvilli
3. Epithelial Cells
These structures significantly enhance the absorptive area.
What are the four principal regions of the large intestine?
- Cecum
- Colon
- Rectum
- Anal canal
The large intestine is involved in water absorption and feces formation.
What is the function of the pancreas?
- digestive enzymes and hormones
- with exocrine cells secreting pancreatic juice into the duodenum.
Its endocrine function involves the secretion of hormones like insulin.
What are the components of bile?(6)
- water
- bile acids
- bile salts
- cholesterol
- lecithin
- bilirubin.
Bilirubin is a key pigment derived from the breakdown of red blood cells.
What is the role of bile in digestion?
- aids in emulsification
- breaking down large lipid globules into smaller droplets for easier digestion.
This process enhances the action of pancreatic lipase.
What are the main digestive processes that occur in the stomach?(4)
- Food is mixed into chyme
- gastric juices activate digestion
- proteins begin to be broken down by pepsin.
- The acidic environment also inactivates salivary amylase.
The acidic environment also inactivates salivary amylase.
What is the main function of the small intestine?
The main function is to absorb nutrients through microvilli and produce intestinal juice.
It also secretes brush-border enzymes for carbohydrate breakdown.
What is the function of the internal and external anal sphincters?
The internal sphincter is involuntary, while the external sphincter is voluntary, controlling the passage of feces.
This coordination is crucial for defecation.
What is the opening that drains into the common opening at the beginning of the bile duct into the duodenum?
Ampula of Vader
Name for Salivary glands
Parotids
Mucosa contains ______________ which contain
mucus secreting cells, parietal cells, chief
cells, and enteroendocrine cells
gastric pits
Diameter and length of small intestine?
Diameter - 2.5cm
Length - 3m
What is attached to the Cecum?
Appendix
4 regions of the Colon
- Ascending
- Transverse
- Descending
- Sigmoid
3 Parts of the Pancreas?
- Head
- Body
- Tail
2 Ducts in the pancreas and where do they empty into?
- Pancreatic duct
- Accessory duct
Empty into the Duodenum
Pancreas - What comprises of 99% of cells form clusters in “Accessory Organs”
Which form 1. acini
-> produce a mixture of fluid and digestive
enzymes called pancreatic juice
Pancreas - What comprises of 1% of cells form clusters in “Accessory Organs”
Pancreatic islets (or islets of Langerhans)
What do Islets produce?(4)
- endocrine hormones insulin
- glucagon
- somatostatin
- pancreatic polypeptide
3 parts of the Gallbladder
- Fundus
- Body
- Neck
What are Liver cells called?
Hepatocytes
Pathway of bile(4)
1.Gallbladder
2.Cystic duct
3. common bile duct
4. Duodenum
What does stercobilin do?
Gives feces its normal brown color
What do lingual lipase digest?
triglycerides into fatty acids
What do Pepsin digest?
Released by chief cells digest proteins into peptide fragments
Brush-border enzymes aid in the breakdown of what?
carbohydrates
What buffers acidic gastric juices?
Sodium bicarbonate
In the large intestine what breaks down the remaining carbs and protein?
Bacteria
Approx. How long does chyme take to form feces?
3-10 hours
What is Catabolic metabolism?
Decomposition reactions which are generally exergonic (produce more energy than they consume)
What is Anabolic metabolism?
Synthesis reactions which are endergonic (consume more energy than they produce)
2 examples of Anabolism?
- Glycogenesis - is the process of converting glucose into glycogen for storage
- Lipogenesis - Synthesis of lipids by cells from glucose or amino acids
2 examples of Catabolism?
- Glycolosis - breaks down glucose (sugar) to produce energy.
- Oxidation of glucose - aerobic cellular respiration
Duodenum, main function ?
First (shortest) Digestion (Deployment/secretion++enzymes + bile)
Jejunum, main function?
Middle Nutrient absorption
Ileum, main function?
Last (longest) Absorbs B12, bile salts
