Chapter 24 Digestive System Flashcards
Another name for complex sugars and polysaccharides
Carbohydrates
In nature sugar is stored as _______?
In a plant sugar is stored as ______?
In an animal sugar is stored as _______?
Carbs
Starch
Glycogen
Digest polysaccharides/carbohydrates into disaccharides and monosaccharides
Amylases/sacharides
Another name for proteins
Polypeptides
Digest polypeptides into amino acids
Proteases
Peptidases
Another name for lipids
Fats, oils, waxes
Triglycerides
Digest fats, oils, waxes into fatty acids and glycerol
Lipases
Another name for nucleic acids
Polynucleotide
Digest polynucleotides into 5 carbon sugars, phosphate, nitrogenous base
Nucleases
6 functions of the digestive tract
- Ingestion
- Mechanical processing
- Digestion
- Secretion
- Absorption
- Elimination
Physical breakdown of food
Chewing(teeth) gnashing (tongue)
Segmentation
Mechanical processing
Breaks larger chunks into smaller ones increase surface area for enzymes to digest
Chewing and gnashing
Regional Churning contractions of the stomach
Segmentation
Chemical breakdown
Digestion
Moisten dissolve chemicals
H20
Coat/lubricate protection against certain acids
Mucus
Digest molecules
Enzymes
Neutralize acids in tract
Buffers
Kill microorganisms dissolve substances/ denature proteins
Acids
Stomach acid PH is ?
1.5
Wave like contractions that’s propel contents thru the tract
Peristalsis
H20
Buffers
Mucus
Acids
Enzymes
Secretions
Putting food into the tract
Ingestion
Transport proteins on lumned surface & digestive epithelium move nutrients, ions, and vitamins into blood stream
Absorption
Removal of waste from the tract (defecate)
Elimination
Duodenum
Jejunum
Ileum all make up the ?
Small intestine
Accessory organs for digestion
Liver
Gall bladder
Pancreas
Appendix
Duodenum
Jejunum
Ileum
10-12 inches
8-10 ft
12ft
Colon is also called
Large intestine
Digestion of sugars occurs in the
Oral cavity
What is the Function of stomach acid ?
Denature proteins
What is happening in the oral cavity ?
Ingestion
Mechanical processing
Digestion
Secretion
What is happening in the stomach ?
Segmentation
Acids and mucus protect stomach lining
H20
Peptidase/proteases digest proteins
Mouth secretes
H20
Mucus
Enzymes
Buffers
What makes up the Mucosa ?
Epithelium tissue
Circular tissue
Muscularis interna
Salvia secretes
H20
Mucus
Amylase = digest carbohydrates
Buffer= neutralize acid
Digestion starts in the ?
Duodenum
Emulsify’s fats breaks into bubbles of fat into chloemicrons
Bile
Secretes bile
Pancreatic juice
Digests all 4 major components
Begin absorption of nutrients
Duodenum
What is pancreatic juice
Amylase
Proteases/ peptidases
Lipases
Nucleases
Most nutritional absorption happens in all 3 part ps of the small intestine
Duedonum
Jejunum
Ileum
Most absorption of h20 occurs in ?
Large intestine
Why are most vitamins absorbed in the large intestine ?
Colon houses numerous bacteria (normal gut flora) which break down waste to make many vitamins
Most nutrient digestion occurs in ?
Duodenum
In each organ the mucosa is made up of 3 layers
ET
CT
Muscularis interna
In the mouth, pharynx, upper 1/3 of the esophagus, rectum, and anus the digestive epithelium is made up of _________ for protection
Straisfied squamous epithelium
In the stomach, small and large intestines the digestive epithelium is made up of ________ for secretion and absorption
Simple columnar epithelium
This is loose connective tissue that lies just deep to the digestive epithelium. It contains numerous blood vessels and lymph vessels
Lamina propia
This is a double layer of smooth muscle that can cause folds in the mucosa. It is also called
Muscularis mucosa or Muscularis interna
This is a layer of dense connective tissue that contains larger blood vessels, nerves, and lymph vessels and nodes that form a network called the submucosal plexus
Submucosa
This is a large double layer of smooth muscle that is responsible for peristalsis and segmentation of the digestive tract
Muscularis externa
The inner layer is circular muscle ; the outer layer is a longitudinal muscle
Muscularis externa
Between the two muscle layers (circular and longitudinal) is a network of large nerves and lymph vessels called
Myenteric plexus
The outer layer of connective tissue that forms the visceral pleura
Serosa
Incisor
Total of 8
4 on top 4 on bottom
Slice and chop food
Canine
Total of 4 tear and slash
Bicuspid/premolar
4
Crush
Molars
12
Grinding
White covering of a tooth (crown)
White covering of tooth (root)
Enamel
Cementum
Most of the tooth is made up of a stuff similar to bone
Dentin
Differences between bone and dentin
Dentin lacks osteoblasts
Esophagus empties into the
Cardia
Two types of muscle contractions in the digestive tract
Peristalsis and segmentation
Tissue lining the
nasopharnyx
Oropharnyx
Laryngeopharnyx
Pseudo stratified ciliated columnar epithelium
Stratified squamous epithelium
Pseudo stratified ciliated columnar
The oblique muscle does what ?
The longitudinal and circular muscle does what ?
Oblique= Segmentation
Longitudinal and circular = peristalsis
Parasympathetic stimulation of these nerves increases peristalsis and segmentation
Myenteric plexus
What is a buffer ?
Resistance changes in PH
The process of swallowing is called ?
Deglutiton
What is the function of the rugae
All for compliance
Secrete pepsinogen
Chief cells
Secrete HCL
Parietal cells
Secrete gastrin increase secretion of chief and parietal cells, increase gastric motility
G cells Apud
Will target Muscularis externa of stomach to increase contractions motility
Gastrin
Chief cells
Parietal cells
g cells
Gastric activity
Four functions of HCL
Kills microbes
Activate Pepcid
Denature proteins
Breakdown plant cell walls
Regulation of gastric activity
Cepahilc phase
Gastric phase
Intestinal phase
Preps stomach to digest foods that enters
Brief just prior to gastric phase
Sight, smell, or thought of food initiates parasympathetic stimulation of vagus nerve
Salivary glands of mouth secrete saliva
Gastric pits secrete acid and pepsinogen
G apud cells secrete gastrin
Cepahilc phase
Long 2-3 hours
Neural stretch receptors in stomach activate the submucosal and Myenteric plexus to begin churning
Presence of peptides in food stimulates G cells to secrete more gastrin
Increased mucus, acid, and enzyme secretion in stomach
Increase gastric motility (churning and mixing)
Gastric phase
Long, serval hours after gastric phase
Stretch receptors ANd chemoreceptors stumalte an enterogastric reflex to inhibit the Myenteric plexus of the stomach
Presence of carbohydrates, peptides, lipids, and acid stimulate release of secretin and CCK from the duodenal mucosa
Enterogastric refelx shows gastric emptying to increase digestion time in the duodenum
Secrete and cck inhibit gastric juice and gastric motility
Intestinal phase
Targets pancreas to secrete more pancreatic juice
Secretin
Target gallbladder and liver increase bile secretion
CCK
Gastric inhibitory peptide/shuts off gastric peptide
GIP gastric inhibitory peptide
10 inches
Digestion, mixing bowl
Duodenal papillae, buffers, acids, enzymes
Duodenum
Some digestion
Most Nutrient absorption
Villi and plicae to increase surface area for absorption
Jejunum
Absorption, controls emptying into the cecum
Peyere patches numerous lymph nodes to remove bacteria from the colon
Illeocecal valve controls emptying
Ileum
Is a double mix gland it is both endocrine and exocrine in function
Pancreas
Pancreatic islets contain alpha and beta cells that secrete glucagon and beta cells secrete insulin
Endocrine function of the pancreas
Acinar cells produce 1L day of pancreatic juice that is secreted into the duodenum to aid in digestion
Exocrine function of the pancreas
Largest visceral organ
Regulate blood and metabolism
Holds up to 25% CO
Contains kupper cells
Synthesizes numerous plasma proteins albumins and clotting factors
Secretes bile
Liver
Is a thick and viscous fluid that contains salts, lipids, water, ions, and bilirubin that aid in lipid digestion by emulsifying fats
Bile
The Branches of the ______ bring oxygenated blood into the liver sinusoids while
The branches of the _______ bring deoxygenated blood that is rich with nutrients and debris from digestion into the same sinusoids. The oxygenated blood and deoxygenated blood mix in the sinusoid and then travels to the ______. The hepatocytes can store nutrients, detoxify drugs and alcohol. K upper cells remove damaged RBCs and bacteria. The clean blood passes through the central vein, haptic veins, and into the inferior vena cava.
Hepatic artery
Hepatic portal vein
Is a small sac about 4 in long and can store and concentrate bile by absorbing some of the water
Gall bladder
It’s main function include absorbing most of the water from feces to compact it,
Absorb vitamins produced by bacteria
Stores fecal waste until defecation occurs
Large intestine (colon)
What is the function of salivary amylase ?
Digest carbohydrates
Within the center of the dentin is a _____ containing blood vessels and nerves which enter the tooth through an ______
Pulp
Apical foramen
Each tooth is held in its alveolus by _______
Periodontal ligaments
The _____ lies just posterior to the trachea and passes through an opening in the diaphragm called the esophageal hiatus
Esophagus
Numerous lymph nodes to remove bacteria from the colon ileocecal valve
Peyers patches