Chapter III Processing, Absorbing and Conversion of Raw Materials Flashcards
also known as gastrointestinal tract is the entire length of tubes from the mouth to the anus. It breakdown and absorbs food through its lining into the blood
Alimentary canal
Commonly known as mucus membrane is the innermost layer of tissue
The Mucosa
Three major functions of mucosa
- Secrete mucus, digestive enzymes, and hormones
- Absorb the end products of digestion into the blood
- Protect against infectious disease.
external to the mucosa, s areolar connective tissue, loaded with
supply of blood and lymphatic vessels, lymphoid follicles, and nerve fibers which enable the
stomach to regain its normal shape after temporarily storing a large meal.
The Submucosa
surrounds the submucosa. It is responsible for
segmentation and peristalsis
Muscularis Externa
act as valves that control food passage from one organ to the next, they also prevent backflow.
sphincters
Also known as the visceral peritoneum, is the outer most layer of the intraperitoneal organs.
Serosa
ordinary fibrous connective tissue that binds the esophagus to surrounding structures
adventitia
a beginning of the long journey of the food that you eat
Chewing
is achieved by the process of mastication and contraction of the smooth muscles of the
digestive tract
Mechanical digestion
starts with the biting of food, with the teeth break apart the food as you chew
Ingestion
swallowed and the peristalsis or muscular action of the esophagus moves the bolus down to the stomach
Bolus
watery mixture of food, saliva, stomach acid and
enzymes, enters the small intestine.
Chyme
The mucosa of the small intestine
is lined with simple columnar epithelial tissue, and is covered in folds called
plicae circulares
first by the absorption of water, and then by the secretion of mucus,
which moves the stool into the rectum, where it waits to be expelled from the body through the
anus.
Egestion or Eliminating Wastes
After the digestion into glucose, fructose and galactose, the nutrients
are absorbed across the enterocyte or the intestinal absorptive cells of the small intestine and into
the blood stream to be transported to the liver.
Carbohydrates
are transported from the
intestinal lumen through the enterocytes, then to the blood
amino acids
are transported from the enterocyte or the intestinal absorptive cells, into blood by a mechanism distinctly different from monosaccharides and amino acids.
Lipids
are extruded from
the Golgi into exocytotic vesicles, which are transported to the basolateral aspect of the enterocyte
chylomicrons
Chylomicrons are transported first into
the lymphatic vessel that penetrates into each villus called
central lacteal
are cleaved by the acidity of the gastric juice in
the stomach into proteins (histones, protamines, etc.) and nucleic acids
nucleoproteins
is hydrolyzed by ribonucleases, while DNA is hydrolyzed by deoxyribonucleases, into nucleotides
Nucleic acid RNA
are absorbed in the small intestine, together
with certain amounts of nucleoside and pentose phosphates.
Purines and pyrimidines
occurs in the cytoplasm of the cell
Glycolysis
The pyruvate molecules enters the mitochondrial matrix where it is converted into twocarbon molecule, bound to Coenzyme A, known as acetyl CoA. Carbon dioxide is released and
NADH is generated
Pyruvate Oxidation
the process how the ATP molecules are manufactured in the cells, particularly within the mitochondria
Cellular Respiration.
The acetyl CoA goes through a cycle of reactions, that ends up in generating the fourcarbon starting molecule. ATP, NADH, and FADH2 (Flavin adenine dinucleotide), are produced,
and carbon dioxide is released.
Citric acid cycle or Krebs cycle
The NADH and FADH2 produced in Krebs cycle deposits their electrons in the electron
transport chain, turning back into their earlier forms of NAD+ and FAD
Oxidative phosphorylation
Protons flow back into the matrix through an enzyme called
ATP Synthase
