Digestive System Flashcards
What are the two groups of the digestive system?
Alimentary and accessory
What group of the digestive system digests food and absorbs materials?
The alimentary controls
What organs are in the alimentary group?
The GI tract, mouth, pharynx, esophagus, large intestines, and anus
What group of organs is technically outside the body?
The alimentary control organs
What organs are accessory?
Teeth, tongue, gallbladder, liver, pancreas, and salivary glands
What is ingestion?
Taking in good
What is propulsion?
Moving food through the body
What happens after you swallow?
Peristalsis
What is peristalsis?
The involuntary mechanism that’s triggered when you begin to swallow
What are the processes of mechanical digestion?
Chewing, mixing, churning, and segmentation
What are chewing, mixing, churning, and segmentation a part of?
Mechanical digestion
What is chemical digestion?
The breaking down of molecules using enzymes
What is absorption?
When chemicals are absorbed across the wall of lumen
What is defecation?
The elimination of indigestible materials
Describe digestive control
The careful control of something technically outside the body
What responds to stimuli?
The sensors in the walls of tract organs
What do sensors in the walls of tract organs do?
They respond to stimuli
What are the two types of receptors in the walls of tract organs?
Mechanoreceptors and chemoreceptors
What do sensors in the walls of tract organs control?
Stretching, osmolarity, pH, presence of substrates, and the end products of digestion
What’s in charge of stretching, osmolarity, pH, presence of substrates, and the end products of digestion?
Sensors in the walls of tract organs
What can activate or inhibit glands?
Sensors in the walls of tract organs
What allows digestive juices to flow into the intestines, and hormones to go into the blood?
Sensors in the walls of tract organs
What is intrinsic control?
Nerve plexuses, short reflexes, and long reflexes
What are short reflexes?
Intrinsic control of the local area/gut
What are long reflexes?
CNS enters/ extrinsic
What releases hormones?
Stimulation
Where are hormones released?
Into interstitial fluid
What can hormones affect?
The same or different digestive organs
What actions do hormones control?
Secretion and contraction
What controls secretion and contraction?
Hormones
What covers most digestive organs?
Visceral peritoneum
What does visceral peritoneum cover?
Most digestive organs
What lies in between the two parts of the peritoneum?
The peritoneal cavity
Where is the peritoneal cavity located?
Between the visceral and parietal peritoneums
What fills the peritoneal cavity?
Serous fluid
What does serous fluid fill?
The peritoneal cavity
What does serous fluid do?
It allows organs to move without damaging each other
What allows organs to move without damaging each other?
Serous fluid
What is the mesentery?
The double layer of peritoneum extending from the body wall
What is the the double layer of peritoneum extending from the body wall called?
The mesentery
What connects to the organs in the body cavity?
The mesentery
What does the mesentery connect to?
It connects to organs in the body cavity
What does the mesentery function as?
A route for nerves, vessels, and lymphatics
What functions as a route for nerves, vessels, and lymphatics?
The mesentery
What is the omenta?
The mesentery
What’s another name for the mesentery?
The omenta
What is the mesentery/omenta also called?
A ligament
What are all the names for the mesentery?
Omenta and ligament
What’s another location for the mesentery?
Retroperitoneal
What adheres to the abdominal wall posterior to the peritoneum?
The retroperitoneal
What are the two locations for the mesentery?
Peritoneal and retroperitoneal
What are retroperitoneal and peritoneal locations for?
The mesentery
What is the retroperitoneal attached to?
Parts of the pancreas and large intestine
What’s attached to parts of the pancreas and large intestine?
The retroperitoneal
What is splanchnic circulation?
Arteries that serve digestive organs
What are arteries that serve digestive organs a part of?
Splanchnic circulation
What is another name for splanchnic circulation?
Hepatic portal circulation
What is hepatic portal circulation?
Splanchnic circulation
What makes up 1/4 of all cardiac output?
Splanchnic circulation
What are the four tunica of the alimentary canal?
Mucosa, submucosa, muscularis externa, serosa
What are the mucosa, submucosa, muscularis externa, and serosa?
They’re the 4 tunics of the alimentary canal
What is the innermost layer of the alimentary canal?
The mucosa
What does the mucosa secrete?
It secretes mucus enzymes
What secretes mucus enzymes?
The mucosa
What does the mucosa absorb?
Nutrients
What absorbs nutrients?
The mucosa
What protects against disease?
The mucosa
What does the mucosa protect against?
Disease
What type of tissue is the mucosa?
Simple columnar epithelial
What layer of the alimentary canal is made up of simple columnar epithelial cells?
The mucosa
What makes up the submucosa?
Loose connective tissue
What layer of the alimentary canal is made up of loose connective tissue cells?
The submucosa
What does the submucosa help transport?
Blood, nervous tissue, and lymph
What helps transport blood, nervous tissue, and lymph in the alimentary canal?
The submucosa
What helps supply blood to the GI wall?
The submucosa
The submucosa supplies ____ to ____
The submucosa supplies blood to the GI wall
Which of the four layers is partially made up of elastic tissue?
The submucosa
What layer is circular on the interior and longitudinal on the external
The muscularis externa
What pattern are the muscularis externa cells in?
The inner cells are circular and the outer are longitudinal
What makes up the sphincters?
The muscularis externa
What does the muscularis externa make up?
The sphincters
What is the muscularis externa in charge of?
Peristalsis and segmentation
What layer is in charge of peristalsis and segmentation?
The muscularis externa
What layer is made up of the visceral peritoneum?
The serosa
What makes up the serosa?
Visceral peritoneum
What type of cells makes up the serosa?
Loose areolar tissues with a simple squamous surface
What layer is made up of loose areolar and simple squamous tissues?
The serosa
What describes the autonomy of the digestive system?
Semiautonomatic
What does the automatic nervous system control in the digestive system?
It regulates activity of glands and smooth muscle in the mucosa
What regulars the activity of glands and smooth muscle in the mucosa?
The automatic nervous system
What controls the digestive system?
Both the sympathetic and parasympathetic systems
What does the hard palate do?
It allows you to roll up food and swallow it
What types of muscles does the tongue have?
Both intrinsic and extrinsic muscles
Where are the taste buds located?
In the papillae
What does the saliva do?
It cleans the mouth, allows taste, moistens food to swallow, and contains enzymes for chemical digestion
What contains enzymes for chemical digestion?
Saliva
What allows you to taste?
Taste buds and saliva
What makes up saliva?
It’s 97-99% water
What is 97-99.5% water?
Saliva
Is saliva acidic or basic?
Saliva is slightly acidic
What’s slightly acidic?
Saliva
What do the enzymes in saliva do?
They analyze and lipase
What analyzes and lipases food?
The enzymes in saliva
What enzymes make up saliva?
Mucin, lysozyme, and IgA proteins
What contains mucin, lysozymes, and IgA proteins?
Saliva
Besides the main things, what else does saliva contain?
Metabolic waste and electrolytes
What contains metabolic waste and electrolytes?
Saliva
What interesting thing can scientists use saliva for?
Diagnostics
What can be used for diagnostics?
Saliva
How long is the esophagus?
25 centimeters long
What organ is collapsed when inactive?
The esophagus
What is a special feature of the esophagus?
It’s collapsed when inactive
What joins the stomach at the cardiac oriface?
The esophagus
Where does the esophagus end?
It ends when it joins the stomach at the cardiac oriface
What sphincter is associated with the esophagus?
The cardiac sphincter
How long is the stomach?
6 to 10 inches
What’s the approximate volume of the stomach?
It’s about 50ml when empty and 2 liters full
What’s a feature of ye stomach?
Rugae
What’s rich in bicarbonate?
The mucosal barrier in the stomach
What makes up the mucosal barrier in the stomach?
Epithelial cells with tight junctions
What is made up of epithelial cells with tight junctions?
The mucosal barrier
What is the mucosal barrier rich in?
Bicarbonate
What continues the work of the oral cavity?
The stomach
What does the stomach deliver?
It delivered chyme to the small intestine
What delivers chyme?
The stomach delivers chyme to the small intestine
What are the three phases of gastric secretion?
Licephalic, gastric, and intestinal
What triggers the licephalic phase?
The smell of food, taste, sight, thought, etc
What causes the licephalic phase?
The reflex in the hypothalamus
How long is the gastric phase?
3-4 hours
What is the main part of the gastric phase?
Digestive liquids
What happens during the intestinal phase?
A surge following by gastric breaks
In what secretion phase is there a surge followed by gastric breaks?
Intestinal
Where is nutrients absorbed?
The small intestine
What does the small intestine do?
Absorb nutrients
How big is the small intestine?
2-4 meters long, 2.5 to 4 centimeters in diameter
Where do accessory organs deposit their contents?
The duodenum of the small intestine
What changes as you move down the small intestine?
The number of crypts, surface area, and microvilli decrease. The number of goblets and Peyers Patches increase
What decreases as you move along the small intestine?
The number of crypts, surface area, and microvilli decrease
What happens to the number of crypts, surface area, and microvilli as you move along the small intestine?
They decrease
What increases as you move along the small intestine?
The number of goblets and Peyers Patches increase
What happens to the number of goblets and Peyers Patches as you move along the small intestine?
They increase
How much intestinal liquids are made daily?
1 to 2 liters
What responds to the irritation of the intestinal tract?
The intestinal liquid, acidic chyme, is produced
When is acidic chyme produced?
When the intestinal system is irritated
Are intestinal liquids alkaline or non-alkaline?
Alkaline
What’s alkaline?
The intestinal liquids
What contains some mucus?
Intestinal liquids
What do intestinal liquids contain some of?
Mucus
What produces bile?
The liver
What does bile do?
It emulsifies fat
What does the liver do?
It produces bile
What emulsifies fat?
Bile
What surrounds the liver?
Visceral peritoneum
What does the visceral peritoneum surround most of?
The liver
What is composed of liver lobules?
The liver
What shape are liver lobules?
Hexagonal
What’s hexagonal in the intestinal system?
Liver lobules
What has a central vein in the middle?
Liver lobules
What do liver lobules have in the middle?
Liver lobules
What do plates f hepatocytes comprise?
Liver lobules
What are liver lobules made of?
Plates of hepatocytes
Where is the hepatic triad located?
At each corner of the hexagon-shaped liver lobules
What’s located at each corner of the hexagonal liver lobules?
A hepatic triad
What makes up the hepatic triad?
The hepatic artery branch and portal, a vein branch, and a bile duct
What do the hepatic artery branch and portal, a vein branch, and a bile duct make up?
The hepatic triad
