Digestive System Flashcards
what are the digestives accessory organs?
teeth, tongue, salivary glands, liver, gallbladder, pancreas
what does the teeth do?
mechanical digestion by breaking appart larger pieces into smaller pieces
what does the tongue do?
mixing food with mucus, lipase, amalayze.
giving taste
rolling food into bolus (ball)
what does the salivary glands do?
what does the liver do?
liver produces bile and sends to gallbladder to get concentrated
what does the gallbladder do?
concentrates bile and releases into intestine to help with digestion
what does the pancreas do?
secretes base to neutralise stomach acids and digestive enzymes
how many pairs of salivary glands do we have?
what are the activities of the digestive tract?
ingestion, mechanical digestion, propulsion, chemical digestion, absorption, defecation
what is the process of ingestion?
Taking in food through the mouth for mastication, enzymes in saliva begin to chemically process the food.
what is the process of mechanical digestion?
breaking larger pieces of food into smaller pieces of food and increases surface area.
what is the process of propulsion?
Muscular contraction moving bolus through the digestive system from mouth to stomach for digestion
what is the process of chemical digestion?
hydrochloric acid, pepsinogen, involves the secretions of enzymes throughout your digestive tract.
These enzymes break the chemical bonds that hold food particles together.
what is the process of absorbtion?
The process by which the products of digestion are absorbed by the blood to be supplied to the rest of the body.
During absorption, the digested products are transported into the blood or lymph through the mucous membrane.
what is the process of defecation?
Defecation follows digestion and is a necessary process by which organisms eliminate a solid, semisolid, or liquid waste material from the digestive tract via the anus.
what are the tissue layers of the digestive tract?
mucosa, submucosa, muscularis, serosa
What does the mucosa do?
Certain cells in the mucosa secrete mucus, digestive enzymes, and hormones.
What does the submucosa do?
Monitors the contents of the stomach and controls smooth muscle contraction and secretion of digestive substances.
what does the muscularis do?
The muscularis externa layer produces churning movements required for mechanical digestion.
what does the serosa do?
Helps to protect the stomach from friction as it expands with food and moves to mix and propel the food.
what is the mucosa composed of?
Stratified squamous
Epithelium, an underlying loose connective tissue layer called lamina propria, and a thin layer of smooth muscle called the muscularis mucosa
what is the submucosa composed of?
Various connective tissues, blood vessels, and parasympathtic nerves.
what is the muscularis composed of?
Two thin layers of smooth muscles arranged as inner circular and outer longitudinal layer, oblique nerves.
what is the serosa composed of?
A layer of simple squamous epithelium, known as mesothelium, and a thin layer of underlying connective tissue.
The serosa has a smooth, slippery surface and secretes a thin, watery secretion known as serous fluid.
what is the enteric nerve system?
Web of sensory neurons, motor neurons, and interneurons embedded in the wall of the gastrointestinal system, beginning in the esophagus and extending down to the anus.
what does the enteric nerve system do?
Control motor functions, local blood flow, mucosal transport and secretions, and modulates immune and endocrine functions.
what are the two enteric nerve networks?
submucosal and the myenteric
What does the myenteric plexus do?
Myenteric plexus increases the tone of the gut and the velocity and intensity of contractions.
what does the submucosal plexus do?
Controls glandular secretion of mucosa, contractions of muscularis mucosae.
