Digestion Flashcards
Where does digestion begin?
The mouth
What teeth specialize in cutting food?
Incisors and Canines
What teeth specialize in grinding and crushing food?
Premolars and Molars
What enzyme is in saliva ? What is it responsible for?
Amylase: responsible for breaking down starch into smaller disaccharides
What is the esophagus?
A muscular tube that passes food from the pharynx to the stomach
What is peristalsis?
When food stretches the walls of the esophagus activating the smooth muscles to undergo wave like contractions
What are the different stomach layers?
Mucosa, submucosa, muscularis, serosa
What are the different stomach layers?
Mucosa, submucosa, muscularis, serosa
What is the mucosa?
The innermost layer of the stomach: extensively folded, secretes gastric juices as well as heals damage to stomach using epithelial cells
What is gastric juices made up of?
Digestive enzymes, acid and mucus
What is the submucosa?
A layer of connective tissue: networks of nerves and blood vessels
What is the muscularis?
Muscle layer: smooth muscles contract to churn and mix good with gastric juices to produce chyme
What is the serosa?
It holds the stomach in pace and secreted a lubricating fluid to eliminate friction against organs
What is the pH of gastric juices?
2.0 - 3.0
what enzyme in digestion is responsible for the breakdown of proteins?
Pepsin
What is Acid Reflux?
The gastroesphageal sphincter doesn’t close entirely, stomach acid enters esophagus. Causes burning sensation in throat
What causes Ulcers?
A bacteria known as H. Pylori can survive the stomach acid by secreting acid neutral enzymes & burrowing into the mucosa. This exposes the stomach lining to the stomach acid.
What is the cure for ulcers?
Antibiotics
Where does most digestion and absorption take place?
The small intestine
What is the diameter and length of the small intestine
2.5 cm in diameter, 7m in length
What is the diameter of the large intestine?
7.6 cm in diameter, 1.5 m in length
What are the three segments of the small intestine?
Duodenum, jejunum and the ileum
What is the specialization of the inner surface of the small intestine?
To provide maximum surface area for the absorption of nutrients
Describe the inner layer of the small intestine
Folded into many ridges that are covered in “finger like” projections called villi
What blood vessels are within the villi? How does the work with the circulatory system
Capillaries are within the villi, this is how nutrients enter the bloodstream
What is the role of the pancreas?
Secreted enzymes that help the digestive process and secretes hormones that are responsible for regulating blood sugar
What enzyme does the pancreas secrete? What does it do?
Amylase, it helps to breakdown starch
What is the function of secretin?
It protects the small Intestine from the acidic contents of the stomach
what does the liver produce?
bile
What is the function of bile?
It emulsifies fats, breaking them down to increase surface area and increase the rate of lipid digestion
Where is bile stored?
The gall bladder
How does bile get released into the body
Lipids entering the body stimulate the gallbladder to contract and release bile through the bile duct into the duodenum
What is the largest part of the large intestine?
The colon
What are the four parts of the colon?
Ascending colon, transverse colon, descending colon, sigmoid colon
What is the last part of the intestine
The rectum
What is the function of the rectum?
It holds waste products of digestion until they are eliminated through the anus
What process reabsorbs most of the water in the large intestine?
Osmosis
