Chapter 8 Through the GI Tract Flashcards
Gut microbiome
A complex ecosystem of friendly micro organisms mostly bacteria that live in the GI tract.
Autonomic nervous system (ANS).
A branch of the nervous system that regulates digestion and internal organs outside of our conscious control.
Sympathetic nervous system (SNS).
A branch of the autonomic nervous system (ANS) that controls the “ fight or flight “ response.
Parasympathetic nervous system (PNS)
A branch of the autonomic nervous system (ANS) that controls the ‘“ rest , digest , and repair “ response.
Olfactory receptors
Receptors in the nasal cavity that sense chemical compounds that create odors.
Olfaction
The act of smelling.
Retronasal olfaction.
Sensing odors from food that’s traveled through the back of our throat and to our nasal passages as we chew and swallow.
Neurotransmitters
Chemicals that send message within the nervous system.
Papillae
Tiny bumps on the tongue that increase the surface area and help move food around the mouth.
Mucous membrane
A thin, porous membrane that lines the mouth, it’s rich with blood vessels and an absorb many substances.
Inflammatory bowel disease (IBD).
A term for two conditions ( Crohn’s disease and Ulcerative colitis). Characterized by chronic inflammation of the gastrointestinal tract, but not limited to the GI tract.
Bolus
The small rounded mass of chewed food.
Pharynx
The cone shaped passageway connecting the oral and nasal cavities to the esophagus and larynx.
Epiglottis
The cartilage flap in the throat that keeps food from entering the trachea and the lungs.
Uvula
The little dangly but that hangs from our upper palate down the back of the throat.
Nasopharynx
The upper part of the pharynx, connecting with the nasal cavity above the soft palate.
Lower esophageal sphincter (LES).
Aka the cardiac sphincter, a ring like muscle at the end of the esophagus which regulates foods passage into the stomach.
Gastroesophageal reflux disease ( gerd)
A digestive malfunction of food and acidic stomach juices splashing back upwards into the esophagus
Short chain fatty acids
Fatty acids with less than six carbon atoms that have important physiological functions.
Chyme
The acidic fluid of gastric juices and partly digested food that passes from the stomach to the small intestine.
Pyloric sphincter
The ring like muscle that lies at the end of the stomach and controls the passage of chyme into the small intestine.
Gastric mucosa
The mucus membrane of the stomach.
Gastric juice
A mix of acids secreted by the stomach to promote digestion; aka gastric acid or stomach acid
Pepsin
An enzyme that breaks down protein into smaller peptides.
Hydrochloride acid
The main acid composing gastric acid
Intrinsic factor
A glycoprotein secreted by the stomach that enables absorption of Vitamin B12
Histamine
A neurotransmitter involved in immune response that also increases gastric acid production.
Ghrelin.
A hormone that stimulates appetite.
Celiac disease
An immune reaction to eating gluten, a protein found in wheat, barley and rye.
Brush border
The distinctive cellular shape and lining that creates a large surface area of the small intestine.
Villous atrophy
A flattened brush border of the small intestine, commonly a sign of intestinal disease.
Duodenum
The first section of the small intestine past the stomach.
Jejunum
The second section of the small intestine past the stomach.
Ileum
The final section of the small intestine.
Bicarbonate
A type of salt that acts as a buffer against acid.
Proteolytic enzymes
Enzymes that break down proteins
Gallbladder
A small pouch under the liver where bike is stored.
Bile
A fluid that aids digestive through emulsification.
Emulsification
When two otherwise unblendable substances eg oil and water are mixed.
Enterohepatic circulation
The process of moving substances from the small intestine to the liver through the portal vein; a key part of digestion and detoxifying potentially harmful chemicals.
Portal vein
A sturdy network of moving vessels that shuttles material from the intestine to the liver.
Concentration gradient
A difference in chemical concentration between two regions. Necessary for diffusion
Minerals
Inorganic substances eg. Calcium or potassium that we use in chemical processes in the body.
Electrolytes
Dissolved mineral ions with an electrical charge.
First pass metabolism
Initial screening of nutrients and other substances via the liver
Lipoprotein
A type of protein that binds to fats to make them water soluble, for circulation.
Chylomicron
A type of lipoprotein that carries fats from the intestines to other parts of the body.
Triglyceride.
A molecule built of three fatty acids attached to a glycerol; the primary storage of fats in the liver.
Hepatic steatosis
Aka non alcoholic fatty liver disease NAFLD. A build up of fats in the liver.
Metabolic syndrome
A cluster of increased risk of metabolic diseases such as heart disease, stroke and diabetes along with high blood pressure and excess body fat.
Sterols
A large family of waxy lipids that are found in plants, animals, fungi and some bacteria.
Very low-density lipoprotein (VLDL).
A large lipoprotein made in the liver that carries triglycerides (fats) to our cells.
Low-density lipoprotein (LDL)
A type of lipoprotein that carries triglycerides (fats) to our cells: can cause plaque leading to heart disease, and is often called “bad cholesterol “.
High density lipoprotein (HDL).
A type of lipoprotein ( the smallest type). that shuttle’s cholesterol back to the liver for recycling; acts as the “cholesterol cleanup crew”. and is often called “ good cholesterol “.
Galactose
A type of simple sugar molecule (monosaccharide).
Deaminate
To remove an amine group ( composed of nitrogen and hydrogen) from an amino acid molecule.
Glucoregulatory hormones
Hormones that help regulate blood sugar
Glucagon
A hormone that helps release stored glucose.
Amylin
A hormone released with insulin that inhibits glucagon secretion, slows gastric emptying and increases satiety.
Somatostatin
A hormone that inhibits gastric secretion.
Ileocecal valve
A sphincter like structure separating the small intestine from the large intestine.
Prostaglandin
A group of fat based compounds with a range of hormone like effects
Gut associated lymphoid tissue ( GALT)
Tissues in the gut that store, release and regulate immune cells and cell signals.
Oligosaccharides
A type of complex carbohydrates
Lactose
A type of sugar found in dairy products.
Sugar alcohols
A class of compounds derived from sugar that typically taste sweet but have lower energy; often used as artificial sweeteners or thickeners.
Fermentation
Digestion of substances by microorganisms eg bacteria and yeasts.
Gut brain axis
The signaling pathway between the gastrointestinal and central nervous systems.
Prebiotics
Substances such as dietary fiber, that feed bacteria in our GI tract.
Probiotics
Foods (eg Sauerkraut, yogurt, or kimchi.) that are fermented and therefore colonized with bacteria or supplements containing bacteria (& sometimes friendly yeast).
Gastrotransmitter
A signaling molecule within the GI tract.
Pepsinogen
An inactive form of the enzyme pepsin secreted by the stomach that helps to break down proteins when activated.
Cholecystokinin (CCK).
A hormone released after we eat protein and/or fat, which increases satiety.
Hypothalamic Amenorrhea
Losing menstrual periods due to injury to or stress by the hypothalamus.
Diurnal
Day based.
Corticotropin- releasing hormone (CRH).
A neurotransmitter that works with leptin and NPY to regulate metabolism and body composition.
Tight cellular junctions
The seal between adjacent epithelial cells, helping to keep food particles and pathogens inside the intestine.
Peptic ulcers
Sores in the stomach
Emesis
Vomiting.
Antibody
An immune system protein produced as a defense against a specific pathogen eg virus.
Immunoglobulin E (Ige)
A specific type of antibody produced by the immune system.
Mast cells
A type of immune system cell that releases histamine and other substances during inflammatory and allergic reactions.
Allergen.
A substance that causes an allergic reaction.
